Add OpenVR SDK to third_party

third_party/openvr/src/headers/openvr.h

+#pragma once
+
+// openvr.h
+//========= Copyright Valve Corporation ============//
+// Dynamically generated file. Do not modify this file directly.
+
+#ifndef _OPENVR_API
+#define _OPENVR_API
+
+#include <stdint.h>
+
+
+
+// vrtypes.h
+#ifndef _INCLUDE_VRTYPES_H
+#define _INCLUDE_VRTYPES_H
+
+// Forward declarations to avoid requiring vulkan.h
+struct VkDevice_T;
+struct VkPhysicalDevice_T;
+struct VkInstance_T;
+struct VkQueue_T;
+
+// Forward declarations to avoid requiring d3d12.h
+struct ID3D12Resource;
+struct ID3D12CommandQueue;
+
+namespace vr
+{
+
+#if defined(__linux__) || defined(__APPLE__) 
+        // The 32-bit version of gcc has the alignment requirement for uint64 and double set to
+        // 4 meaning that even with #pragma pack(8) these types will only be four-byte aligned.
+        // The 64-bit version of gcc has the alignment requirement for these types set to
+        // 8 meaning that unless we use #pragma pack(4) our structures will get bigger.
+        // The 64-bit structure packing has to match the 32-bit structure packing for each platform.
+        #pragma pack( push, 4 )
+#else
+        #pragma pack( push, 8 )
+#endif
+
+typedef void* glSharedTextureHandle_t;
+typedef int32_t glInt_t;
+typedef uint32_t glUInt_t;
+
+// right-handed system
+// +y is up
+// +x is to the right
+// -z is going away from you
+// Distance unit is  meters
+struct HmdMatrix34_t
+{
+        float m[3][4];
+};
+
+struct HmdMatrix44_t
+{
+        float m[4][4];
+};
+
+struct HmdVector3_t
+{
+        float v[3];
+};
+
+struct HmdVector4_t
+{
+        float v[4];
+};
+
+struct HmdVector3d_t
+{
+        double v[3];
+};
+
+struct HmdVector2_t
+{
+        float v[2];
+};
+
+struct HmdQuaternion_t
+{
+        double w, x, y, z;
+};
+
+struct HmdColor_t
+{
+        float r, g, b, a;
+};
+
+struct HmdQuad_t
+{
+        HmdVector3_t vCorners[ 4 ];
+};
+
+struct HmdRect2_t
+{
+        HmdVector2_t vTopLeft;
+        HmdVector2_t vBottomRight;
+};
+
+/** Used to return the post-distortion UVs for each color channel. 
+* UVs range from 0 to 1 with 0,0 in the upper left corner of the 
+* source render target. The 0,0 to 1,1 range covers a single eye. */
+struct DistortionCoordinates_t
+{
+        float rfRed[2];
+        float rfGreen[2];
+        float rfBlue[2];
+};
+
+enum EVREye
+{
+        Eye_Left = 0,
+        Eye_Right = 1
+};
+
+enum ETextureType
+{
+        TextureType_DirectX = 0, // Handle is an ID3D11Texture
+        TextureType_OpenGL = 1,  // Handle is an OpenGL texture name or an OpenGL render buffer name, depending on submit flags
+        TextureType_Vulkan = 2, // Handle is a pointer to a VRVulkanTextureData_t structure
+        TextureType_IOSurface = 3, // Handle is a macOS cross-process-sharable IOSurface
+        TextureType_DirectX12 = 4, // Handle is a pointer to a D3D12TextureData_t structure
+};
+
+enum EColorSpace
+{
+        ColorSpace_Auto = 0,    // Assumes 'gamma' for 8-bit per component formats, otherwise 'linear'.  This mirrors the DXGI formats which have _SRGB variants.
+        ColorSpace_Gamma = 1,   // Texture data can be displayed directly on the display without any conversion (a.k.a. display native format).
+        ColorSpace_Linear = 2,  // Same as gamma but has been converted to a linear representation using DXGI's sRGB conversion algorithm.
+};
+
+struct Texture_t
+{
+        void* handle; // See ETextureType definition above
+        ETextureType eType;
+        EColorSpace eColorSpace;
+};
+
+// Handle to a shared texture (HANDLE on Windows obtained using OpenSharedResource).
+typedef uint64_t SharedTextureHandle_t;
+#define INVALID_SHARED_TEXTURE_HANDLE   ((vr::SharedTextureHandle_t)0)
+
+enum ETrackingResult
+{
+        TrackingResult_Uninitialized                    = 1,
+
+        TrackingResult_Calibrating_InProgress   = 100,
+        TrackingResult_Calibrating_OutOfRange   = 101,
+
+        TrackingResult_Running_OK                               = 200,
+        TrackingResult_Running_OutOfRange               = 201,
+};
+
+static const uint32_t k_unMaxDriverDebugResponseSize = 32768;
+
+/** Used to pass device IDs to API calls */
+typedef uint32_t TrackedDeviceIndex_t;
+static const uint32_t k_unTrackedDeviceIndex_Hmd = 0;
+static const uint32_t k_unMaxTrackedDeviceCount = 16;
+static const uint32_t k_unTrackedDeviceIndexOther = 0xFFFFFFFE;
+static const uint32_t k_unTrackedDeviceIndexInvalid = 0xFFFFFFFF;
+
+/** Describes what kind of object is being tracked at a given ID */
+enum ETrackedDeviceClass
+{
+        TrackedDeviceClass_Invalid = 0,                         // the ID was not valid.
+        TrackedDeviceClass_HMD = 1,                                     // Head-Mounted Displays
+        TrackedDeviceClass_Controller = 2,                      // Tracked controllers
+        TrackedDeviceClass_GenericTracker = 3,          // Generic trackers, similar to controllers
+        TrackedDeviceClass_TrackingReference = 4,       // Camera and base stations that serve as tracking reference points
+};
+
+
+/** Describes what specific role associated with a tracked device */
+enum ETrackedControllerRole
+{
+        TrackedControllerRole_Invalid = 0,                                      // Invalid value for controller type
+        TrackedControllerRole_LeftHand = 1,                                     // Tracked device associated with the left hand
+        TrackedControllerRole_RightHand = 2,                            // Tracked device associated with the right hand
+};
+
+
+/** describes a single pose for a tracked object */
+struct TrackedDevicePose_t
+{
+        HmdMatrix34_t mDeviceToAbsoluteTracking;
+        HmdVector3_t vVelocity;                         // velocity in tracker space in m/s
+        HmdVector3_t vAngularVelocity;          // angular velocity in radians/s (?)
+        ETrackingResult eTrackingResult;
+        bool bPoseIsValid;
+
+        // This indicates that there is a device connected for this spot in the pose array.
+        // It could go from true to false if the user unplugs the device.
+        bool bDeviceIsConnected;
+};
+
+/** Identifies which style of tracking origin the application wants to use
+* for the poses it is requesting */
+enum ETrackingUniverseOrigin
+{
+        TrackingUniverseSeated = 0,             // Poses are provided relative to the seated zero pose
+        TrackingUniverseStanding = 1,   // Poses are provided relative to the safe bounds configured by the user
+        TrackingUniverseRawAndUncalibrated = 2, // Poses are provided in the coordinate system defined by the driver.  It has Y up and is unified for devices of the same driver. You usually don't want this one.
+};
+
+// Refers to a single container of properties
+typedef uint64_t PropertyContainerHandle_t;
+typedef uint32_t PropertyTypeTag_t;
+
+static const PropertyContainerHandle_t k_ulInvalidPropertyContainer = 0;
+static const PropertyTypeTag_t k_unInvalidPropertyTag = 0;
+
+// Use these tags to set/get common types as struct properties
+static const PropertyTypeTag_t k_unFloatPropertyTag = 1;
+static const PropertyTypeTag_t k_unInt32PropertyTag = 2;
+static const PropertyTypeTag_t k_unUint64PropertyTag = 3;
+static const PropertyTypeTag_t k_unBoolPropertyTag = 4;
+static const PropertyTypeTag_t k_unStringPropertyTag = 5;
+
+static const PropertyTypeTag_t k_unHmdMatrix34PropertyTag = 20;
+static const PropertyTypeTag_t k_unHmdMatrix44PropertyTag = 21;
+static const PropertyTypeTag_t k_unHmdVector3PropertyTag = 22;
+static const PropertyTypeTag_t k_unHmdVector4PropertyTag = 23;
+
+static const PropertyTypeTag_t k_unHiddenAreaPropertyTag = 30;
+
+static const PropertyTypeTag_t k_unOpenVRInternalReserved_Start = 1000;
+static const PropertyTypeTag_t k_unOpenVRInternalReserved_End = 10000;
+
+
+/** Each entry in this enum represents a property that can be retrieved about a
+* tracked device. Many fields are only valid for one ETrackedDeviceClass. */
+enum ETrackedDeviceProperty
+{
+        Prop_Invalid                                                            = 0,
+
+        // general properties that apply to all device classes
+        Prop_TrackingSystemName_String                          = 1000,
+        Prop_ModelNumber_String                                         = 1001,
+        Prop_SerialNumber_String                                        = 1002,
+        Prop_RenderModelName_String                                     = 1003,
+        Prop_WillDriftInYaw_Bool                                        = 1004,
+        Prop_ManufacturerName_String                            = 1005,
+        Prop_TrackingFirmwareVersion_String                     = 1006,
+        Prop_HardwareRevision_String                            = 1007,
+        Prop_AllWirelessDongleDescriptions_String       = 1008,
+        Prop_ConnectedWirelessDongle_String                     = 1009,
+        Prop_DeviceIsWireless_Bool                                      = 1010,
+        Prop_DeviceIsCharging_Bool                                      = 1011,
+        Prop_DeviceBatteryPercentage_Float                      = 1012, // 0 is empty, 1 is full
+        Prop_StatusDisplayTransform_Matrix34            = 1013,
+        Prop_Firmware_UpdateAvailable_Bool                      = 1014,
+        Prop_Firmware_ManualUpdate_Bool                         = 1015,
+        Prop_Firmware_ManualUpdateURL_String            = 1016,
+        Prop_HardwareRevision_Uint64                            = 1017,
+        Prop_FirmwareVersion_Uint64                                     = 1018,
+        Prop_FPGAVersion_Uint64                                         = 1019,
+        Prop_VRCVersion_Uint64                                          = 1020,
+        Prop_RadioVersion_Uint64                                        = 1021,
+        Prop_DongleVersion_Uint64                                       = 1022,
+        Prop_BlockServerShutdown_Bool                           = 1023,
+        Prop_CanUnifyCoordinateSystemWithHmd_Bool       = 1024,
+        Prop_ContainsProximitySensor_Bool                       = 1025,
+        Prop_DeviceProvidesBatteryStatus_Bool           = 1026,
+        Prop_DeviceCanPowerOff_Bool                                     = 1027,
+        Prop_Firmware_ProgrammingTarget_String          = 1028,
+        Prop_DeviceClass_Int32                                          = 1029,
+        Prop_HasCamera_Bool                                                     = 1030,
+        Prop_DriverVersion_String                   = 1031,
+        Prop_Firmware_ForceUpdateRequired_Bool      = 1032,
+        Prop_ViveSystemButtonFixRequired_Bool           = 1033,
+        Prop_ParentDriver_Uint64                                        = 1034,
+
+
+        // Properties that are unique to TrackedDeviceClass_HMD
+        Prop_ReportsTimeSinceVSync_Bool                         = 2000,
+        Prop_SecondsFromVsyncToPhotons_Float            = 2001,
+        Prop_DisplayFrequency_Float                                     = 2002,
+        Prop_UserIpdMeters_Float                                        = 2003,
+        Prop_CurrentUniverseId_Uint64                           = 2004, 
+        Prop_PreviousUniverseId_Uint64                          = 2005, 
+        Prop_DisplayFirmwareVersion_Uint64                      = 2006,
+        Prop_IsOnDesktop_Bool                                           = 2007,
+        Prop_DisplayMCType_Int32                                        = 2008,
+        Prop_DisplayMCOffset_Float                                      = 2009,
+        Prop_DisplayMCScale_Float                                       = 2010,
+        Prop_EdidVendorID_Int32                                         = 2011,
+        Prop_DisplayMCImageLeft_String              = 2012,
+        Prop_DisplayMCImageRight_String             = 2013,
+        Prop_DisplayGCBlackClamp_Float                          = 2014,
+        Prop_EdidProductID_Int32                                        = 2015,
+        Prop_CameraToHeadTransform_Matrix34                     = 2016,
+        Prop_DisplayGCType_Int32                                        = 2017,
+        Prop_DisplayGCOffset_Float                                      = 2018,
+        Prop_DisplayGCScale_Float                                       = 2019,
+        Prop_DisplayGCPrescale_Float                            = 2020,
+        Prop_DisplayGCImage_String                                      = 2021,
+        Prop_LensCenterLeftU_Float                                      = 2022,
+        Prop_LensCenterLeftV_Float                                      = 2023,
+        Prop_LensCenterRightU_Float                                     = 2024,
+        Prop_LensCenterRightV_Float                                     = 2025,
+        Prop_UserHeadToEyeDepthMeters_Float                     = 2026,
+        Prop_CameraFirmwareVersion_Uint64                       = 2027,
+        Prop_CameraFirmwareDescription_String           = 2028,
+        Prop_DisplayFPGAVersion_Uint64                          = 2029,
+        Prop_DisplayBootloaderVersion_Uint64            = 2030,
+        Prop_DisplayHardwareVersion_Uint64                      = 2031,
+        Prop_AudioFirmwareVersion_Uint64                        = 2032,
+        Prop_CameraCompatibilityMode_Int32                      = 2033,
+        Prop_ScreenshotHorizontalFieldOfViewDegrees_Float = 2034,
+        Prop_ScreenshotVerticalFieldOfViewDegrees_Float = 2035,
+        Prop_DisplaySuppressed_Bool                                     = 2036,
+        Prop_DisplayAllowNightMode_Bool                         = 2037,
+        Prop_DisplayMCImageWidth_Int32                          = 2038,
+        Prop_DisplayMCImageHeight_Int32                         = 2039,
+        Prop_DisplayMCImageNumChannels_Int32            = 2040,
+        Prop_DisplayMCImageData_Binary                          = 2041,
+        Prop_UsesDriverDirectMode_Bool                          = 2042,
+
+        // Properties that are unique to TrackedDeviceClass_Controller
+        Prop_AttachedDeviceId_String                            = 3000,
+        Prop_SupportedButtons_Uint64                            = 3001,
+        Prop_Axis0Type_Int32                                            = 3002, // Return value is of type EVRControllerAxisType
+        Prop_Axis1Type_Int32                                            = 3003, // Return value is of type EVRControllerAxisType
+        Prop_Axis2Type_Int32                                            = 3004, // Return value is of type EVRControllerAxisType
+        Prop_Axis3Type_Int32                                            = 3005, // Return value is of type EVRControllerAxisType
+        Prop_Axis4Type_Int32                                            = 3006, // Return value is of type EVRControllerAxisType
+        Prop_ControllerRoleHint_Int32                           = 3007, // Return value is of type ETrackedControllerRole
+
+        // Properties that are unique to TrackedDeviceClass_TrackingReference
+        Prop_FieldOfViewLeftDegrees_Float                       = 4000,
+        Prop_FieldOfViewRightDegrees_Float                      = 4001,
+        Prop_FieldOfViewTopDegrees_Float                        = 4002,
+        Prop_FieldOfViewBottomDegrees_Float                     = 4003,
+        Prop_TrackingRangeMinimumMeters_Float           = 4004,
+        Prop_TrackingRangeMaximumMeters_Float           = 4005,
+        Prop_ModeLabel_String                                           = 4006,
+
+        // Properties that are used for user interface like icons names
+        Prop_IconPathName_String                                                = 5000, // usually a directory named "icons"
+        Prop_NamedIconPathDeviceOff_String                              = 5001, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceSearching_String                = 5002, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceSearchingAlert_String   = 5003, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceReady_String                    = 5004, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceReadyAlert_String               = 5005, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceNotReady_String                 = 5006, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceStandby_String                  = 5007, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+        Prop_NamedIconPathDeviceAlertLow_String                 = 5008, // PNG for static icon, or GIF for animation, 50x32 for headsets and 32x32 for others
+
+        // Properties that are used by helpers, but are opaque to applications
+        Prop_DisplayHiddenArea_Binary_Start                             = 5100,
+        Prop_DisplayHiddenArea_Binary_End                               = 5150,
+
+        // Properties that are unique to drivers
+        Prop_UserConfigPath_String                                      = 6000,
+        Prop_InstallPath_String                                         = 6001,
+
+        // Vendors are free to expose private debug data in this reserved region
+        Prop_VendorSpecific_Reserved_Start                      = 10000,
+        Prop_VendorSpecific_Reserved_End                        = 10999,
+};
+
+/** No string property will ever be longer than this length */
+static const uint32_t k_unMaxPropertyStringSize = 32 * 1024;
+
+/** Used to return errors that occur when reading properties. */
+enum ETrackedPropertyError
+{
+        TrackedProp_Success                                             = 0,
+        TrackedProp_WrongDataType                               = 1,
+        TrackedProp_WrongDeviceClass                    = 2,
+        TrackedProp_BufferTooSmall                              = 3,
+        TrackedProp_UnknownProperty                             = 4, // Driver has not set the property (and may not ever).
+        TrackedProp_InvalidDevice                               = 5,
+        TrackedProp_CouldNotContactServer               = 6,
+        TrackedProp_ValueNotProvidedByDevice    = 7,
+        TrackedProp_StringExceedsMaximumLength  = 8,
+        TrackedProp_NotYetAvailable                             = 9, // The property value isn't known yet, but is expected soon. Call again later.
+        TrackedProp_PermissionDenied                    = 10,
+        TrackedProp_InvalidOperation                    = 11,
+};
+
+/** Allows the application to control what part of the provided texture will be used in the
+* frame buffer. */
+struct VRTextureBounds_t
+{
+        float uMin, vMin;
+        float uMax, vMax;
+};
+
+
+/** Allows the application to control how scene textures are used by the compositor when calling Submit. */
+enum EVRSubmitFlags
+{
+        // Simple render path. App submits rendered left and right eye images with no lens distortion correction applied.
+        Submit_Default = 0x00,
+
+        // App submits final left and right eye images with lens distortion already applied (lens distortion makes the images appear
+        // barrel distorted with chromatic aberration correction applied). The app would have used the data returned by
+        // vr::IVRSystem::ComputeDistortion() to apply the correct distortion to the rendered images before calling Submit().
+        Submit_LensDistortionAlreadyApplied = 0x01,
+
+        // If the texture pointer passed in is actually a renderbuffer (e.g. for MSAA in OpenGL) then set this flag.
+        Submit_GlRenderBuffer = 0x02,
+
+        // Do not use
+        Submit_Reserved = 0x04,
+};
+
+/** Data required for passing Vulkan textures to IVRCompositor::Submit.
+* Be sure to call OpenVR_Shutdown before destroying these resources. */
+struct VRVulkanTextureData_t
+{
+        uint64_t m_nImage; // VkImage
+        VkDevice_T *m_pDevice;
+        VkPhysicalDevice_T *m_pPhysicalDevice;
+        VkInstance_T *m_pInstance;
+        VkQueue_T *m_pQueue;
+        uint32_t m_nQueueFamilyIndex;
+        uint32_t m_nWidth, m_nHeight, m_nFormat, m_nSampleCount;
+};
+
+/** Data required for passing D3D12 textures to IVRCompositor::Submit.
+* Be sure to call OpenVR_Shutdown before destroying these resources. */
+struct D3D12TextureData_t
+{
+        ID3D12Resource *m_pResource;
+        ID3D12CommandQueue *m_pCommandQueue;
+        uint32_t m_nNodeMask;
+};
+
+/** Status of the overall system or tracked objects */
+enum EVRState
+{
+        VRState_Undefined = -1,
+        VRState_Off = 0,
+        VRState_Searching = 1,
+        VRState_Searching_Alert = 2,
+        VRState_Ready = 3,
+        VRState_Ready_Alert = 4,
+        VRState_NotReady = 5,
+        VRState_Standby = 6,
+        VRState_Ready_Alert_Low = 7,
+};
+
+/** The types of events that could be posted (and what the parameters mean for each event type) */
+enum EVREventType
+{
+        VREvent_None = 0,
+
+        VREvent_TrackedDeviceActivated          = 100,
+        VREvent_TrackedDeviceDeactivated        = 101,
+        VREvent_TrackedDeviceUpdated            = 102,
+        VREvent_TrackedDeviceUserInteractionStarted     = 103,
+        VREvent_TrackedDeviceUserInteractionEnded       = 104,
+        VREvent_IpdChanged                                      = 105,
+        VREvent_EnterStandbyMode                        = 106,
+        VREvent_LeaveStandbyMode                        = 107,
+        VREvent_TrackedDeviceRoleChanged        = 108,
+        VREvent_WatchdogWakeUpRequested         = 109,
+        VREvent_LensDistortionChanged           = 110,
+        VREvent_PropertyChanged                         = 111,
+
+        VREvent_ButtonPress                                     = 200, // data is controller
+        VREvent_ButtonUnpress                           = 201, // data is controller
+        VREvent_ButtonTouch                                     = 202, // data is controller
+        VREvent_ButtonUntouch                           = 203, // data is controller
+
+        VREvent_MouseMove                                       = 300, // data is mouse
+        VREvent_MouseButtonDown                         = 301, // data is mouse
+        VREvent_MouseButtonUp                           = 302, // data is mouse
+        VREvent_FocusEnter                                      = 303, // data is overlay
+        VREvent_FocusLeave                                      = 304, // data is overlay
+        VREvent_Scroll                                          = 305, // data is mouse
+        VREvent_TouchPadMove                            = 306, // data is mouse
+        VREvent_OverlayFocusChanged                     = 307, // data is overlay, global event
+
+        VREvent_InputFocusCaptured                      = 400, // data is process DEPRECATED
+        VREvent_InputFocusReleased                      = 401, // data is process DEPRECATED
+        VREvent_SceneFocusLost                          = 402, // data is process
+        VREvent_SceneFocusGained                        = 403, // data is process
+        VREvent_SceneApplicationChanged         = 404, // data is process - The App actually drawing the scene changed (usually to or from the compositor)
+        VREvent_SceneFocusChanged                       = 405, // data is process - New app got access to draw the scene
+        VREvent_InputFocusChanged                       = 406, // data is process
+        VREvent_SceneApplicationSecondaryRenderingStarted = 407, // data is process
+
+        VREvent_HideRenderModels                        = 410, // Sent to the scene application to request hiding render models temporarily
+        VREvent_ShowRenderModels                        = 411, // Sent to the scene application to request restoring render model visibility
+
+        VREvent_OverlayShown                            = 500,
+        VREvent_OverlayHidden                           = 501,
+        VREvent_DashboardActivated                      = 502,
+        VREvent_DashboardDeactivated            = 503,
+        VREvent_DashboardThumbSelected          = 504, // Sent to the overlay manager - data is overlay
+        VREvent_DashboardRequested                      = 505, // Sent to the overlay manager - data is overlay
+        VREvent_ResetDashboard                          = 506, // Send to the overlay manager
+        VREvent_RenderToast                                     = 507, // Send to the dashboard to render a toast - data is the notification ID
+        VREvent_ImageLoaded                                     = 508, // Sent to overlays when a SetOverlayRaw or SetOverlayFromFile call finishes loading
+        VREvent_ShowKeyboard                            = 509, // Sent to keyboard renderer in the dashboard to invoke it
+        VREvent_HideKeyboard                            = 510, // Sent to keyboard renderer in the dashboard to hide it
+        VREvent_OverlayGamepadFocusGained       = 511, // Sent to an overlay when IVROverlay::SetFocusOverlay is called on it
+        VREvent_OverlayGamepadFocusLost         = 512, // Send to an overlay when it previously had focus and IVROverlay::SetFocusOverlay is called on something else
+        VREvent_OverlaySharedTextureChanged = 513,
+        VREvent_DashboardGuideButtonDown        = 514,
+        VREvent_DashboardGuideButtonUp          = 515,
+        VREvent_ScreenshotTriggered                     = 516, // Screenshot button combo was pressed, Dashboard should request a screenshot
+        VREvent_ImageFailed                                     = 517, // Sent to overlays when a SetOverlayRaw or SetOverlayfromFail fails to load
+        VREvent_DashboardOverlayCreated         = 518,
+
+        // Screenshot API
+        VREvent_RequestScreenshot                               = 520, // Sent by vrclient application to compositor to take a screenshot
+        VREvent_ScreenshotTaken                                 = 521, // Sent by compositor to the application that the screenshot has been taken
+        VREvent_ScreenshotFailed                                = 522, // Sent by compositor to the application that the screenshot failed to be taken
+        VREvent_SubmitScreenshotToDashboard             = 523, // Sent by compositor to the dashboard that a completed screenshot was submitted
+        VREvent_ScreenshotProgressToDashboard   = 524, // Sent by compositor to the dashboard that a completed screenshot was submitted
+
+        VREvent_PrimaryDashboardDeviceChanged   = 525,
+
+        VREvent_Notification_Shown                              = 600,
+        VREvent_Notification_Hidden                             = 601,
+        VREvent_Notification_BeginInteraction   = 602,
+        VREvent_Notification_Destroyed                  = 603,
+
+        VREvent_Quit                                                    = 700, // data is process
+        VREvent_ProcessQuit                                             = 701, // data is process
+        VREvent_QuitAborted_UserPrompt                  = 702, // data is process
+        VREvent_QuitAcknowledged                                = 703, // data is process
+        VREvent_DriverRequestedQuit                             = 704, // The driver has requested that SteamVR shut down
+
+        VREvent_ChaperoneDataHasChanged                 = 800,
+        VREvent_ChaperoneUniverseHasChanged             = 801,
+        VREvent_ChaperoneTempDataHasChanged             = 802,
+        VREvent_ChaperoneSettingsHaveChanged    = 803,
+        VREvent_SeatedZeroPoseReset                             = 804,
+
+        VREvent_AudioSettingsHaveChanged                = 820,
+
+        VREvent_BackgroundSettingHasChanged             = 850,
+        VREvent_CameraSettingsHaveChanged               = 851,
+        VREvent_ReprojectionSettingHasChanged   = 852,
+        VREvent_ModelSkinSettingsHaveChanged    = 853,
+        VREvent_EnvironmentSettingsHaveChanged  = 854,
+        VREvent_PowerSettingsHaveChanged                = 855,
+
+        VREvent_StatusUpdate                                    = 900,
+
+        VREvent_MCImageUpdated                                  = 1000,
+
+        VREvent_FirmwareUpdateStarted                   = 1100,
+        VREvent_FirmwareUpdateFinished                  = 1101,
+
+        VREvent_KeyboardClosed                                  = 1200,
+        VREvent_KeyboardCharInput                               = 1201,
+        VREvent_KeyboardDone                                    = 1202, // Sent when DONE button clicked on keyboard
+
+        VREvent_ApplicationTransitionStarted            = 1300,
+        VREvent_ApplicationTransitionAborted            = 1301,
+        VREvent_ApplicationTransitionNewAppStarted      = 1302,
+        VREvent_ApplicationListUpdated                          = 1303,
+        VREvent_ApplicationMimeTypeLoad                         = 1304,
+        VREvent_ApplicationTransitionNewAppLaunchComplete = 1305,
+
+        VREvent_Compositor_MirrorWindowShown            = 1400,
+        VREvent_Compositor_MirrorWindowHidden           = 1401,
+        VREvent_Compositor_ChaperoneBoundsShown         = 1410,
+        VREvent_Compositor_ChaperoneBoundsHidden        = 1411,
+
+        VREvent_TrackedCamera_StartVideoStream  = 1500,
+        VREvent_TrackedCamera_StopVideoStream   = 1501,
+        VREvent_TrackedCamera_PauseVideoStream  = 1502,
+        VREvent_TrackedCamera_ResumeVideoStream = 1503,
+        VREvent_TrackedCamera_EditingSurface    = 1550,
+
+        VREvent_PerformanceTest_EnableCapture   = 1600,
+        VREvent_PerformanceTest_DisableCapture  = 1601,
+        VREvent_PerformanceTest_FidelityLevel   = 1602,
+
+        VREvent_MessageOverlay_Closed                   = 1650,
+        
+        // Vendors are free to expose private events in this reserved region
+        VREvent_VendorSpecific_Reserved_Start   = 10000,
+        VREvent_VendorSpecific_Reserved_End             = 19999,
+};
+
+
+/** Level of Hmd activity */
+enum EDeviceActivityLevel
+{
+        k_EDeviceActivityLevel_Unknown = -1,
+        k_EDeviceActivityLevel_Idle = 0,
+        k_EDeviceActivityLevel_UserInteraction = 1,
+        k_EDeviceActivityLevel_UserInteraction_Timeout = 2,
+        k_EDeviceActivityLevel_Standby = 3,
+};
+
+
+/** VR controller button and axis IDs */
+enum EVRButtonId
+{
+        k_EButton_System                        = 0,
+        k_EButton_ApplicationMenu       = 1,
+        k_EButton_Grip                          = 2,
+        k_EButton_DPad_Left                     = 3,
+        k_EButton_DPad_Up                       = 4,
+        k_EButton_DPad_Right            = 5,
+        k_EButton_DPad_Down                     = 6,
+        k_EButton_A                                     = 7,
+        
+        k_EButton_ProximitySensor   = 31,
+
+        k_EButton_Axis0                         = 32,
+        k_EButton_Axis1                         = 33,
+        k_EButton_Axis2                         = 34,
+        k_EButton_Axis3                         = 35,
+        k_EButton_Axis4                         = 36,
+
+        // aliases for well known controllers
+        k_EButton_SteamVR_Touchpad      = k_EButton_Axis0,
+        k_EButton_SteamVR_Trigger       = k_EButton_Axis1,
+
+        k_EButton_Dashboard_Back        = k_EButton_Grip,
+
+        k_EButton_Max                           = 64
+};
+
+inline uint64_t ButtonMaskFromId( EVRButtonId id ) { return 1ull << id; }
+
+/** used for controller button events */
+struct VREvent_Controller_t
+{
+        uint32_t button; // EVRButtonId enum
+};
+
+
+/** used for simulated mouse events in overlay space */
+enum EVRMouseButton
+{
+        VRMouseButton_Left                                      = 0x0001,
+        VRMouseButton_Right                                     = 0x0002,
+        VRMouseButton_Middle                            = 0x0004,
+};
+
+
+/** used for simulated mouse events in overlay space */
+struct VREvent_Mouse_t
+{
+        float x, y; // co-ords are in GL space, bottom left of the texture is 0,0
+        uint32_t button; // EVRMouseButton enum
+};
+
+/** used for simulated mouse wheel scroll in overlay space */
+struct VREvent_Scroll_t
+{
+        float xdelta, ydelta; // movement in fraction of the pad traversed since last delta, 1.0 for a full swipe
+        uint32_t repeatCount;
+};
+
+/** when in mouse input mode you can receive data from the touchpad, these events are only sent if the users finger
+   is on the touchpad (or just released from it) 
+**/
+struct VREvent_TouchPadMove_t
+{
+        // true if the users finger is detected on the touch pad
+        bool bFingerDown;
+
+        // How long the finger has been down in seconds
+        float flSecondsFingerDown;
+
+        // These values indicate the starting finger position (so you can do some basic swipe stuff)
+        float fValueXFirst;
+        float fValueYFirst;
+
+        // This is the raw sampled coordinate without deadzoning
+        float fValueXRaw;
+        float fValueYRaw;
+};
+
+/** notification related events. Details will still change at this point */
+struct VREvent_Notification_t
+{
+        uint64_t ulUserValue;
+        uint32_t notificationId;
+};
+
+/** Used for events about processes */
+struct VREvent_Process_t
+{
+        uint32_t pid;
+        uint32_t oldPid;
+        bool bForced;
+};
+
+
+/** Used for a few events about overlays */
+struct VREvent_Overlay_t
+{
+        uint64_t overlayHandle;
+};
+
+
+/** Used for a few events about overlays */
+struct VREvent_Status_t
+{
+        uint32_t statusState; // EVRState enum
+};
+
+/** Used for keyboard events **/
+struct VREvent_Keyboard_t
+{
+        char cNewInput[8];      // Up to 11 bytes of new input
+        uint64_t uUserValue;    // Possible flags about the new input
+};
+
+struct VREvent_Ipd_t
+{
+        float ipdMeters;
+};
+
+struct VREvent_Chaperone_t
+{
+        uint64_t m_nPreviousUniverse;
+        uint64_t m_nCurrentUniverse;
+};
+
+/** Not actually used for any events */
+struct VREvent_Reserved_t
+{
+        uint64_t reserved0;
+        uint64_t reserved1;
+};
+
+struct VREvent_PerformanceTest_t
+{
+        uint32_t m_nFidelityLevel;
+};
+
+struct VREvent_SeatedZeroPoseReset_t
+{
+        bool bResetBySystemMenu;
+};
+
+struct VREvent_Screenshot_t
+{
+        uint32_t handle;
+        uint32_t type;
+};
+
+struct VREvent_ScreenshotProgress_t
+{
+        float progress;
+};
+
+struct VREvent_ApplicationLaunch_t
+{
+        uint32_t pid;
+        uint32_t unArgsHandle;
+};
+
+struct VREvent_EditingCameraSurface_t
+{
+        uint64_t overlayHandle;
+        uint32_t nVisualMode;
+};
+
+struct VREvent_MessageOverlay_t
+{
+        uint32_t unVRMessageOverlayResponse; // vr::VRMessageOverlayResponse enum
+};
+
+struct VREvent_Property_t
+{
+        PropertyContainerHandle_t container;
+        ETrackedDeviceProperty prop;
+};
+
+/** NOTE!!! If you change this you MUST manually update openvr_interop.cs.py */
+typedef union
+{
+        VREvent_Reserved_t reserved;
+        VREvent_Controller_t controller;
+        VREvent_Mouse_t mouse;
+        VREvent_Scroll_t scroll;
+        VREvent_Process_t process;
+        VREvent_Notification_t notification;
+        VREvent_Overlay_t overlay;
+        VREvent_Status_t status;
+        VREvent_Keyboard_t keyboard;
+        VREvent_Ipd_t ipd;
+        VREvent_Chaperone_t chaperone;
+        VREvent_PerformanceTest_t performanceTest;
+        VREvent_TouchPadMove_t touchPadMove;
+        VREvent_SeatedZeroPoseReset_t seatedZeroPoseReset;
+        VREvent_Screenshot_t screenshot;
+        VREvent_ScreenshotProgress_t screenshotProgress;
+        VREvent_ApplicationLaunch_t applicationLaunch;
+        VREvent_EditingCameraSurface_t cameraSurface;
+        VREvent_MessageOverlay_t messageOverlay;
+        VREvent_Property_t property;
+} VREvent_Data_t;
+
+/** An event posted by the server to all running applications */
+struct VREvent_t
+{
+        uint32_t eventType; // EVREventType enum
+        TrackedDeviceIndex_t trackedDeviceIndex;
+        float eventAgeSeconds;
+        // event data must be the end of the struct as its size is variable
+        VREvent_Data_t data;
+};
+
+
+/** The mesh to draw into the stencil (or depth) buffer to perform 
+* early stencil (or depth) kills of pixels that will never appear on the HMD.
+* This mesh draws on all the pixels that will be hidden after distortion. 
+*
+* If the HMD does not provide a visible area mesh pVertexData will be
+* NULL and unTriangleCount will be 0. */
+struct HiddenAreaMesh_t
+{
+        const HmdVector2_t *pVertexData;
+        uint32_t unTriangleCount;
+};
+
+
+enum EHiddenAreaMeshType
+{
+        k_eHiddenAreaMesh_Standard = 0,
+        k_eHiddenAreaMesh_Inverse = 1,
+        k_eHiddenAreaMesh_LineLoop = 2,
+
+        k_eHiddenAreaMesh_Max = 3,
+};
+
+
+/** Identifies what kind of axis is on the controller at index n. Read this type 
+* with pVRSystem->Get( nControllerDeviceIndex, Prop_Axis0Type_Int32 + n );
+*/
+enum EVRControllerAxisType
+{
+        k_eControllerAxis_None = 0,
+        k_eControllerAxis_TrackPad = 1,
+        k_eControllerAxis_Joystick = 2,
+        k_eControllerAxis_Trigger = 3, // Analog trigger data is in the X axis
+};
+
+
+/** contains information about one axis on the controller */
+struct VRControllerAxis_t
+{
+        float x; // Ranges from -1.0 to 1.0 for joysticks and track pads. Ranges from 0.0 to 1.0 for triggers were 0 is fully released.
+        float y; // Ranges from -1.0 to 1.0 for joysticks and track pads. Is always 0.0 for triggers.
+};
+
+
+/** the number of axes in the controller state */
+static const uint32_t k_unControllerStateAxisCount = 5;
+
+
+/** Holds all the state of a controller at one moment in time. */
+struct VRControllerState001_t
+{
+        // If packet num matches that on your prior call, then the controller state hasn't been changed since 
+        // your last call and there is no need to process it
+        uint32_t unPacketNum;
+
+        // bit flags for each of the buttons. Use ButtonMaskFromId to turn an ID into a mask
+        uint64_t ulButtonPressed;
+        uint64_t ulButtonTouched;
+
+        // Axis data for the controller's analog inputs
+        VRControllerAxis_t rAxis[ k_unControllerStateAxisCount ];
+};
+
+
+typedef VRControllerState001_t VRControllerState_t;
+
+
+/** determines how to provide output to the application of various event processing functions. */
+enum EVRControllerEventOutputType
+{
+        ControllerEventOutput_OSEvents = 0,
+        ControllerEventOutput_VREvents = 1,
+};
+
+
+
+/** Collision Bounds Style */
+enum ECollisionBoundsStyle
+{
+        COLLISION_BOUNDS_STYLE_BEGINNER = 0,
+        COLLISION_BOUNDS_STYLE_INTERMEDIATE,
+        COLLISION_BOUNDS_STYLE_SQUARES,
+        COLLISION_BOUNDS_STYLE_ADVANCED,
+        COLLISION_BOUNDS_STYLE_NONE,
+
+        COLLISION_BOUNDS_STYLE_COUNT
+};
+
+/** Allows the application to customize how the overlay appears in the compositor */
+struct Compositor_OverlaySettings
+{
+        uint32_t size; // sizeof(Compositor_OverlaySettings)
+        bool curved, antialias;
+        float scale, distance, alpha;
+        float uOffset, vOffset, uScale, vScale;
+        float gridDivs, gridWidth, gridScale;
+        HmdMatrix44_t transform;
+};
+
+/** used to refer to a single VR overlay */
+typedef uint64_t VROverlayHandle_t;
+
+static const VROverlayHandle_t k_ulOverlayHandleInvalid = 0;
+
+/** Errors that can occur around VR overlays */
+enum EVROverlayError
+{
+        VROverlayError_None                                             = 0,
+
+        VROverlayError_UnknownOverlay                   = 10,
+        VROverlayError_InvalidHandle                    = 11,
+        VROverlayError_PermissionDenied                 = 12,
+        VROverlayError_OverlayLimitExceeded             = 13, // No more overlays could be created because the maximum number already exist
+        VROverlayError_WrongVisibilityType              = 14,
+        VROverlayError_KeyTooLong                               = 15,
+        VROverlayError_NameTooLong                              = 16,
+        VROverlayError_KeyInUse                                 = 17,
+        VROverlayError_WrongTransformType               = 18,
+        VROverlayError_InvalidTrackedDevice             = 19,
+        VROverlayError_InvalidParameter                 = 20,
+        VROverlayError_ThumbnailCantBeDestroyed = 21,
+        VROverlayError_ArrayTooSmall                    = 22,
+        VROverlayError_RequestFailed                    = 23,
+        VROverlayError_InvalidTexture                   = 24,
+        VROverlayError_UnableToLoadFile                 = 25,
+        VROverlayError_KeyboardAlreadyInUse             = 26,
+        VROverlayError_NoNeighbor                               = 27,
+        VROverlayError_TooManyMaskPrimitives    = 29,
+        VROverlayError_BadMaskPrimitive                 = 30,
+};
+
+/** enum values to pass in to VR_Init to identify whether the application will 
+* draw a 3D scene. */
+enum EVRApplicationType
+{
+        VRApplication_Other = 0,                // Some other kind of application that isn't covered by the other entries 
+        VRApplication_Scene     = 1,            // Application will submit 3D frames 
+        VRApplication_Overlay = 2,              // Application only interacts with overlays
+        VRApplication_Background = 3,   // Application should not start SteamVR if it's not already running, and should not
+                                                                        // keep it running if everything else quits.
+        VRApplication_Utility = 4,              // Init should not try to load any drivers. The application needs access to utility
+                                                                        // interfaces (like IVRSettings and IVRApplications) but not hardware.
+        VRApplication_VRMonitor = 5,    // Reserved for vrmonitor
+        VRApplication_SteamWatchdog = 6,// Reserved for Steam
+
+        VRApplication_Max
+};
+
+
+/** error codes for firmware */
+enum EVRFirmwareError
+{
+        VRFirmwareError_None = 0,
+        VRFirmwareError_Success = 1,
+        VRFirmwareError_Fail = 2,
+};
+
+
+/** error codes for notifications */
+enum EVRNotificationError
+{
+        VRNotificationError_OK = 0,
+        VRNotificationError_InvalidNotificationId = 100,
+        VRNotificationError_NotificationQueueFull = 101,
+        VRNotificationError_InvalidOverlayHandle = 102,
+        VRNotificationError_SystemWithUserValueAlreadyExists = 103,
+};
+
+
+/** error codes returned by Vr_Init */
+
+// Please add adequate error description to https://developer.valvesoftware.com/w/index.php?title=Category:SteamVRHelp
+enum EVRInitError
+{
+        VRInitError_None        = 0,
+        VRInitError_Unknown = 1,
+
+        VRInitError_Init_InstallationNotFound           = 100,
+        VRInitError_Init_InstallationCorrupt            = 101,
+        VRInitError_Init_VRClientDLLNotFound            = 102,
+        VRInitError_Init_FileNotFound                           = 103,
+        VRInitError_Init_FactoryNotFound                        = 104,
+        VRInitError_Init_InterfaceNotFound                      = 105,
+        VRInitError_Init_InvalidInterface                       = 106,
+        VRInitError_Init_UserConfigDirectoryInvalid = 107,
+        VRInitError_Init_HmdNotFound                            = 108,
+        VRInitError_Init_NotInitialized                         = 109,
+        VRInitError_Init_PathRegistryNotFound           = 110,
+        VRInitError_Init_NoConfigPath                           = 111,
+        VRInitError_Init_NoLogPath                                      = 112,
+        VRInitError_Init_PathRegistryNotWritable        = 113,
+        VRInitError_Init_AppInfoInitFailed                      = 114,
+        VRInitError_Init_Retry                                          = 115, // Used internally to cause retries to vrserver
+        VRInitError_Init_InitCanceledByUser                     = 116, // The calling application should silently exit. The user canceled app startup
+        VRInitError_Init_AnotherAppLaunching            = 117, 
+        VRInitError_Init_SettingsInitFailed                     = 118, 
+        VRInitError_Init_ShuttingDown                           = 119,
+        VRInitError_Init_TooManyObjects                         = 120,
+        VRInitError_Init_NoServerForBackgroundApp       = 121,
+        VRInitError_Init_NotSupportedWithCompositor     = 122,
+        VRInitError_Init_NotAvailableToUtilityApps      = 123,
+        VRInitError_Init_Internal                                       = 124,
+        VRInitError_Init_HmdDriverIdIsNone                      = 125,
+        VRInitError_Init_HmdNotFoundPresenceFailed      = 126,
+        VRInitError_Init_VRMonitorNotFound                      = 127,
+        VRInitError_Init_VRMonitorStartupFailed         = 128,
+        VRInitError_Init_LowPowerWatchdogNotSupported = 129, 
+        VRInitError_Init_InvalidApplicationType         = 130,
+        VRInitError_Init_NotAvailableToWatchdogApps = 131,
+        VRInitError_Init_WatchdogDisabledInSettings = 132,
+        VRInitError_Init_VRDashboardNotFound            = 133,
+        VRInitError_Init_VRDashboardStartupFailed       = 134,
+
+        VRInitError_Driver_Failed                               = 200,
+        VRInitError_Driver_Unknown                              = 201,
+        VRInitError_Driver_HmdUnknown                   = 202,
+        VRInitError_Driver_NotLoaded                    = 203,
+        VRInitError_Driver_RuntimeOutOfDate             = 204,
+        VRInitError_Driver_HmdInUse                             = 205,
+        VRInitError_Driver_NotCalibrated                = 206,
+        VRInitError_Driver_CalibrationInvalid   = 207,
+        VRInitError_Driver_HmdDisplayNotFound   = 208,
+        VRInitError_Driver_TrackedDeviceInterfaceUnknown = 209,
+        // VRInitError_Driver_HmdDisplayNotFoundAfterFix         = 210, // not needed: here for historic reasons
+        VRInitError_Driver_HmdDriverIdOutOfBounds = 211,
+        VRInitError_Driver_HmdDisplayMirrored  = 212,
+
+        VRInitError_IPC_ServerInitFailed                = 300,
+        VRInitError_IPC_ConnectFailed                   = 301,
+        VRInitError_IPC_SharedStateInitFailed   = 302,
+        VRInitError_IPC_CompositorInitFailed    = 303,
+        VRInitError_IPC_MutexInitFailed                 = 304,
+        VRInitError_IPC_Failed                                  = 305,
+        VRInitError_IPC_CompositorConnectFailed = 306,
+        VRInitError_IPC_CompositorInvalidConnectResponse = 307,
+        VRInitError_IPC_ConnectFailedAfterMultipleAttempts = 308,
+
+        VRInitError_Compositor_Failed                                   = 400,
+        VRInitError_Compositor_D3D11HardwareRequired    = 401,
+        VRInitError_Compositor_FirmwareRequiresUpdate   = 402,
+        VRInitError_Compositor_OverlayInitFailed                = 403,
+        VRInitError_Compositor_ScreenshotsInitFailed    = 404,
+
+        VRInitError_VendorSpecific_UnableToConnectToOculusRuntime = 1000,
+
+        VRInitError_VendorSpecific_HmdFound_CantOpenDevice                              = 1101,
+        VRInitError_VendorSpecific_HmdFound_UnableToRequestConfigStart  = 1102,
+        VRInitError_VendorSpecific_HmdFound_NoStoredConfig                              = 1103,
+        VRInitError_VendorSpecific_HmdFound_ConfigTooBig                                = 1104,
+        VRInitError_VendorSpecific_HmdFound_ConfigTooSmall                              = 1105,
+        VRInitError_VendorSpecific_HmdFound_UnableToInitZLib                    = 1106,
+        VRInitError_VendorSpecific_HmdFound_CantReadFirmwareVersion     = 1107,
+        VRInitError_VendorSpecific_HmdFound_UnableToSendUserDataStart   = 1108,
+        VRInitError_VendorSpecific_HmdFound_UnableToGetUserDataStart    = 1109,
+        VRInitError_VendorSpecific_HmdFound_UnableToGetUserDataNext             = 1110,
+        VRInitError_VendorSpecific_HmdFound_UserDataAddressRange                = 1111,
+        VRInitError_VendorSpecific_HmdFound_UserDataError                               = 1112,
+        VRInitError_VendorSpecific_HmdFound_ConfigFailedSanityCheck             = 1113,
+
+        VRInitError_Steam_SteamInstallationNotFound = 2000,
+};
+
+enum EVRScreenshotType
+{
+        VRScreenshotType_None = 0,
+        VRScreenshotType_Mono = 1, // left eye only
+        VRScreenshotType_Stereo = 2,
+        VRScreenshotType_Cubemap = 3,
+        VRScreenshotType_MonoPanorama = 4,
+        VRScreenshotType_StereoPanorama = 5
+};
+
+enum EVRScreenshotPropertyFilenames
+{
+        VRScreenshotPropertyFilenames_Preview = 0,
+        VRScreenshotPropertyFilenames_VR = 1,
+};
+
+enum EVRTrackedCameraError
+{
+        VRTrackedCameraError_None                       = 0,
+        VRTrackedCameraError_OperationFailed            = 100,
+        VRTrackedCameraError_InvalidHandle              = 101,  
+        VRTrackedCameraError_InvalidFrameHeaderVersion  = 102,
+        VRTrackedCameraError_OutOfHandles               = 103,
+        VRTrackedCameraError_IPCFailure                 = 104,
+        VRTrackedCameraError_NotSupportedForThisDevice  = 105,
+        VRTrackedCameraError_SharedMemoryFailure        = 106,
+        VRTrackedCameraError_FrameBufferingFailure      = 107,
+        VRTrackedCameraError_StreamSetupFailure         = 108,
+        VRTrackedCameraError_InvalidGLTextureId         = 109,
+        VRTrackedCameraError_InvalidSharedTextureHandle = 110,
+        VRTrackedCameraError_FailedToGetGLTextureId     = 111,
+        VRTrackedCameraError_SharedTextureFailure       = 112,
+        VRTrackedCameraError_NoFrameAvailable           = 113,
+        VRTrackedCameraError_InvalidArgument            = 114,
+        VRTrackedCameraError_InvalidFrameBufferSize     = 115,
+};
+
+enum EVRTrackedCameraFrameType
+{
+        VRTrackedCameraFrameType_Distorted = 0,                 // This is the camera video frame size in pixels, still distorted.
+        VRTrackedCameraFrameType_Undistorted,                   // In pixels, an undistorted inscribed rectangle region without invalid regions. This size is subject to changes shortly.
+        VRTrackedCameraFrameType_MaximumUndistorted,    // In pixels, maximum undistorted with invalid regions. Non zero alpha component identifies valid regions.
+        MAX_CAMERA_FRAME_TYPES
+};
+
+typedef uint64_t TrackedCameraHandle_t;
+#define INVALID_TRACKED_CAMERA_HANDLE   ((vr::TrackedCameraHandle_t)0)
+
+struct CameraVideoStreamFrameHeader_t
+{
+        EVRTrackedCameraFrameType eFrameType;
+
+        uint32_t nWidth;
+        uint32_t nHeight;
+        uint32_t nBytesPerPixel;
+
+        uint32_t nFrameSequence;
+
+        TrackedDevicePose_t standingTrackedDevicePose;
+};
+
+// Screenshot types
+typedef uint32_t ScreenshotHandle_t;
+
+static const uint32_t k_unScreenshotHandleInvalid = 0;
+
+#pragma pack( pop )
+
+// figure out how to import from the VR API dll
+#if defined(_WIN32)
+
+#ifdef VR_API_EXPORT
+#define VR_INTERFACE extern "C" __declspec( dllexport )
+#else
+#define VR_INTERFACE extern "C" __declspec( dllimport )
+#endif
+
+#elif defined(__GNUC__) || defined(COMPILER_GCC) || defined(__APPLE__)
+
+#ifdef VR_API_EXPORT
+#define VR_INTERFACE extern "C" __attribute__((visibility("default")))
+#else
+#define VR_INTERFACE extern "C" 
+#endif
+
+#else
+#error "Unsupported Platform."
+#endif
+
+
+#if defined( _WIN32 )
+#define VR_CALLTYPE __cdecl
+#else
+#define VR_CALLTYPE 
+#endif
+
+} // namespace vr
+
+#endif // _INCLUDE_VRTYPES_H
+
+
+// vrannotation.h
+#ifdef API_GEN
+# define VR_CLANG_ATTR(ATTR) __attribute__((annotate( ATTR )))
+#else
+# define VR_CLANG_ATTR(ATTR)
+#endif
+
+#define VR_METHOD_DESC(DESC) VR_CLANG_ATTR( "desc:" #DESC ";" )
+#define VR_IGNOREATTR() VR_CLANG_ATTR( "ignore" )
+#define VR_OUT_STRUCT() VR_CLANG_ATTR( "out_struct: ;" )
+#define VR_OUT_STRING() VR_CLANG_ATTR( "out_string: ;" )
+#define VR_OUT_ARRAY_CALL(COUNTER,FUNCTION,PARAMS) VR_CLANG_ATTR( "out_array_call:" #COUNTER "," #FUNCTION "," #PARAMS ";" )
+#define VR_OUT_ARRAY_COUNT(COUNTER) VR_CLANG_ATTR( "out_array_count:" #COUNTER ";" )
+#define VR_ARRAY_COUNT(COUNTER) VR_CLANG_ATTR( "array_count:" #COUNTER ";" )
+#define VR_ARRAY_COUNT_D(COUNTER, DESC) VR_CLANG_ATTR( "array_count:" #COUNTER ";desc:" #DESC )
+#define VR_BUFFER_COUNT(COUNTER) VR_CLANG_ATTR( "buffer_count:" #COUNTER ";" )
+#define VR_OUT_BUFFER_COUNT(COUNTER) VR_CLANG_ATTR( "out_buffer_count:" #COUNTER ";" )
+#define VR_OUT_STRING_COUNT(COUNTER) VR_CLANG_ATTR( "out_string_count:" #COUNTER ";" )
+
+// ivrsystem.h
+namespace vr
+{
+
+class IVRSystem
+{
+public:
+
+
+        // ------------------------------------
+        // Display Methods
+        // ------------------------------------
+
+        /** Suggested size for the intermediate render target that the distortion pulls from. */
+        virtual void GetRecommendedRenderTargetSize( uint32_t *pnWidth, uint32_t *pnHeight ) = 0;
+
+        /** The projection matrix for the specified eye */
+        virtual HmdMatrix44_t GetProjectionMatrix( EVREye eEye, float fNearZ, float fFarZ ) = 0;
+
+        /** The components necessary to build your own projection matrix in case your
+        * application is doing something fancy like infinite Z */
+        virtual void GetProjectionRaw( EVREye eEye, float *pfLeft, float *pfRight, float *pfTop, float *pfBottom ) = 0;
+
+        /** Gets the result of the distortion function for the specified eye and input UVs. UVs go from 0,0 in 
+        * the upper left of that eye's viewport and 1,1 in the lower right of that eye's viewport.
+        * Returns true for success. Otherwise, returns false, and distortion coordinates are not suitable. */
+        virtual bool ComputeDistortion( EVREye eEye, float fU, float fV, DistortionCoordinates_t *pDistortionCoordinates ) = 0;
+
+        /** Returns the transform from eye space to the head space. Eye space is the per-eye flavor of head
+        * space that provides stereo disparity. Instead of Model * View * Projection the sequence is Model * View * Eye^-1 * Projection. 
+        * Normally View and Eye^-1 will be multiplied together and treated as View in your application. 
+        */
+        virtual HmdMatrix34_t GetEyeToHeadTransform( EVREye eEye ) = 0;
+
+        /** Returns the number of elapsed seconds since the last recorded vsync event. This 
+        *       will come from a vsync timer event in the timer if possible or from the application-reported
+        *   time if that is not available. If no vsync times are available the function will 
+        *   return zero for vsync time and frame counter and return false from the method. */
+        virtual bool GetTimeSinceLastVsync( float *pfSecondsSinceLastVsync, uint64_t *pulFrameCounter ) = 0;
+
+        /** [D3D9 Only]
+        * Returns the adapter index that the user should pass into CreateDevice to set up D3D9 in such
+        * a way that it can go full screen exclusive on the HMD. Returns -1 if there was an error.
+        */
+        virtual int32_t GetD3D9AdapterIndex() = 0;
+
+        /** [D3D10/11 Only]
+        * Returns the adapter index that the user should pass into EnumAdapters to create the device 
+        * and swap chain in DX10 and DX11. If an error occurs the index will be set to -1.
+        */
+        virtual void GetDXGIOutputInfo( int32_t *pnAdapterIndex ) = 0;
+
+        // ------------------------------------
+        // Display Mode methods
+        // ------------------------------------
+
+        /** Use to determine if the headset display is part of the desktop (i.e. extended) or hidden (i.e. direct mode). */
+        virtual bool IsDisplayOnDesktop() = 0;
+
+        /** Set the display visibility (true = extended, false = direct mode).  Return value of true indicates that the change was successful. */
+        virtual bool SetDisplayVisibility( bool bIsVisibleOnDesktop ) = 0;
+
+        // ------------------------------------
+        // Tracking Methods
+        // ------------------------------------
+
+        /** The pose that the tracker thinks that the HMD will be in at the specified number of seconds into the 
+        * future. Pass 0 to get the state at the instant the method is called. Most of the time the application should
+        * calculate the time until the photons will be emitted from the display and pass that time into the method.
+        *
+        * This is roughly analogous to the inverse of the view matrix in most applications, though 
+        * many games will need to do some additional rotation or translation on top of the rotation
+        * and translation provided by the head pose.
+        *
+        * For devices where bPoseIsValid is true the application can use the pose to position the device
+        * in question. The provided array can be any size up to k_unMaxTrackedDeviceCount. 
+        *
+        * Seated experiences should call this method with TrackingUniverseSeated and receive poses relative
+        * to the seated zero pose. Standing experiences should call this method with TrackingUniverseStanding 
+        * and receive poses relative to the Chaperone Play Area. TrackingUniverseRawAndUncalibrated should 
+        * probably not be used unless the application is the Chaperone calibration tool itself, but will provide
+        * poses relative to the hardware-specific coordinate system in the driver.
+        */
+        virtual void GetDeviceToAbsoluteTrackingPose( ETrackingUniverseOrigin eOrigin, float fPredictedSecondsToPhotonsFromNow, VR_ARRAY_COUNT(unTrackedDevicePoseArrayCount) TrackedDevicePose_t *pTrackedDevicePoseArray, uint32_t unTrackedDevicePoseArrayCount ) = 0;
+
+        /** Sets the zero pose for the seated tracker coordinate system to the current position and yaw of the HMD. After 
+        * ResetSeatedZeroPose all GetDeviceToAbsoluteTrackingPose calls that pass TrackingUniverseSeated as the origin 
+        * will be relative to this new zero pose. The new zero coordinate system will not change the fact that the Y axis 
+        * is up in the real world, so the next pose returned from GetDeviceToAbsoluteTrackingPose after a call to 
+        * ResetSeatedZeroPose may not be exactly an identity matrix.
+        *
+        * NOTE: This function overrides the user's previously saved seated zero pose and should only be called as the result of a user action. 
+        * Users are also able to set their seated zero pose via the OpenVR Dashboard.
+        **/
+        virtual void ResetSeatedZeroPose() = 0;
+
+        /** Returns the transform from the seated zero pose to the standing absolute tracking system. This allows 
+        * applications to represent the seated origin to used or transform object positions from one coordinate
+        * system to the other. 
+        *
+        * The seated origin may or may not be inside the Play Area or Collision Bounds returned by IVRChaperone. Its position 
+        * depends on what the user has set from the Dashboard settings and previous calls to ResetSeatedZeroPose. */
+        virtual HmdMatrix34_t GetSeatedZeroPoseToStandingAbsoluteTrackingPose() = 0;
+
+        /** Returns the transform from the tracking origin to the standing absolute tracking system. This allows
+        * applications to convert from raw tracking space to the calibrated standing coordinate system. */
+        virtual HmdMatrix34_t GetRawZeroPoseToStandingAbsoluteTrackingPose() = 0;
+
+        /** Get a sorted array of device indices of a given class of tracked devices (e.g. controllers).  Devices are sorted right to left
+        * relative to the specified tracked device (default: hmd -- pass in -1 for absolute tracking space).  Returns the number of devices
+        * in the list, or the size of the array needed if not large enough. */
+        virtual uint32_t GetSortedTrackedDeviceIndicesOfClass( ETrackedDeviceClass eTrackedDeviceClass, VR_ARRAY_COUNT(unTrackedDeviceIndexArrayCount) vr::TrackedDeviceIndex_t *punTrackedDeviceIndexArray, uint32_t unTrackedDeviceIndexArrayCount, vr::TrackedDeviceIndex_t unRelativeToTrackedDeviceIndex = k_unTrackedDeviceIndex_Hmd ) = 0;
+
+        /** Returns the level of activity on the device. */
+        virtual EDeviceActivityLevel GetTrackedDeviceActivityLevel( vr::TrackedDeviceIndex_t unDeviceId ) = 0;
+
+        /** Convenience utility to apply the specified transform to the specified pose.
+        *   This properly transforms all pose components, including velocity and angular velocity
+        */
+        virtual void ApplyTransform( TrackedDevicePose_t *pOutputPose, const TrackedDevicePose_t *pTrackedDevicePose, const HmdMatrix34_t *pTransform ) = 0;
+
+        /** Returns the device index associated with a specific role, for example the left hand or the right hand. */
+        virtual vr::TrackedDeviceIndex_t GetTrackedDeviceIndexForControllerRole( vr::ETrackedControllerRole unDeviceType ) = 0;
+
+        /** Returns the controller type associated with a device index. */
+        virtual vr::ETrackedControllerRole GetControllerRoleForTrackedDeviceIndex( vr::TrackedDeviceIndex_t unDeviceIndex ) = 0;
+
+        // ------------------------------------
+        // Property methods
+        // ------------------------------------
+
+        /** Returns the device class of a tracked device. If there has not been a device connected in this slot
+        * since the application started this function will return TrackedDevice_Invalid. For previous detected
+        * devices the function will return the previously observed device class. 
+        *
+        * To determine which devices exist on the system, just loop from 0 to k_unMaxTrackedDeviceCount and check
+        * the device class. Every device with something other than TrackedDevice_Invalid is associated with an 
+        * actual tracked device. */
+        virtual ETrackedDeviceClass GetTrackedDeviceClass( vr::TrackedDeviceIndex_t unDeviceIndex ) = 0;
+
+        /** Returns true if there is a device connected in this slot. */
+        virtual bool IsTrackedDeviceConnected( vr::TrackedDeviceIndex_t unDeviceIndex ) = 0;
+
+        /** Returns a bool property. If the device index is not valid or the property is not a bool type this function will return false. */
+        virtual bool GetBoolTrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** Returns a float property. If the device index is not valid or the property is not a float type this function will return 0. */
+        virtual float GetFloatTrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** Returns an int property. If the device index is not valid or the property is not a int type this function will return 0. */
+        virtual int32_t GetInt32TrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** Returns a uint64 property. If the device index is not valid or the property is not a uint64 type this function will return 0. */
+        virtual uint64_t GetUint64TrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** Returns a matrix property. If the device index is not valid or the property is not a matrix type, this function will return identity. */
+        virtual HmdMatrix34_t GetMatrix34TrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** Returns a string property. If the device index is not valid or the property is not a string type this function will 
+        * return 0. Otherwise it returns the length of the number of bytes necessary to hold this string including the trailing
+        * null. Strings will always fit in buffers of k_unMaxPropertyStringSize characters. */
+        virtual uint32_t GetStringTrackedDeviceProperty( vr::TrackedDeviceIndex_t unDeviceIndex, ETrackedDeviceProperty prop, VR_OUT_STRING() char *pchValue, uint32_t unBufferSize, ETrackedPropertyError *pError = 0L ) = 0;
+
+        /** returns a string that corresponds with the specified property error. The string will be the name 
+        * of the error enum value for all valid error codes */
+        virtual const char *GetPropErrorNameFromEnum( ETrackedPropertyError error ) = 0;
+
+        // ------------------------------------
+        // Event methods
+        // ------------------------------------
+
+        /** Returns true and fills the event with the next event on the queue if there is one. If there are no events
+        * this method returns false. uncbVREvent should be the size in bytes of the VREvent_t struct */
+        virtual bool PollNextEvent( VREvent_t *pEvent, uint32_t uncbVREvent ) = 0;
+
+        /** Returns true and fills the event with the next event on the queue if there is one. If there are no events
+        * this method returns false. Fills in the pose of the associated tracked device in the provided pose struct. 
+        * This pose will always be older than the call to this function and should not be used to render the device. 
+        uncbVREvent should be the size in bytes of the VREvent_t struct */
+        virtual bool PollNextEventWithPose( ETrackingUniverseOrigin eOrigin, VREvent_t *pEvent, uint32_t uncbVREvent, vr::TrackedDevicePose_t *pTrackedDevicePose ) = 0;
+
+        /** returns the name of an EVREvent enum value */
+        virtual const char *GetEventTypeNameFromEnum( EVREventType eType ) = 0;
+
+        // ------------------------------------
+        // Rendering helper methods
+        // ------------------------------------
+
+        /** Returns the hidden area mesh for the current HMD. The pixels covered by this mesh will never be seen by the user after the lens distortion is
+        * applied based on visibility to the panels. If this HMD does not have a hidden area mesh, the vertex data and count will be NULL and 0 respectively.
+        * This mesh is meant to be rendered into the stencil buffer (or into the depth buffer setting nearz) before rendering each eye's view. 
+        * This will improve performance by letting the GPU early-reject pixels the user will never see before running the pixel shader.
+        * NOTE: Render this mesh with backface culling disabled since the winding order of the vertices can be different per-HMD or per-eye.
+        * Setting the bInverse argument to true will produce the visible area mesh that is commonly used in place of full-screen quads. The visible area mesh covers all of the pixels the hidden area mesh does not cover.
+        * Setting the bLineLoop argument will return a line loop of vertices in HiddenAreaMesh_t->pVertexData with HiddenAreaMesh_t->unTriangleCount set to the number of vertices.
+        */
+        virtual HiddenAreaMesh_t GetHiddenAreaMesh( EVREye eEye, EHiddenAreaMeshType type = k_eHiddenAreaMesh_Standard ) = 0;
+
+        // ------------------------------------
+        // Controller methods
+        // ------------------------------------
+
+        /** Fills the supplied struct with the current state of the controller. Returns false if the controller index
+        * is invalid. */
+        virtual bool GetControllerState( vr::TrackedDeviceIndex_t unControllerDeviceIndex, vr::VRControllerState_t *pControllerState, uint32_t unControllerStateSize ) = 0;
+
+        /** fills the supplied struct with the current state of the controller and the provided pose with the pose of 
+        * the controller when the controller state was updated most recently. Use this form if you need a precise controller
+        * pose as input to your application when the user presses or releases a button. */
+        virtual bool GetControllerStateWithPose( ETrackingUniverseOrigin eOrigin, vr::TrackedDeviceIndex_t unControllerDeviceIndex, vr::VRControllerState_t *pControllerState, uint32_t unControllerStateSize, TrackedDevicePose_t *pTrackedDevicePose ) = 0;
+
+        /** Trigger a single haptic pulse on a controller. After this call the application may not trigger another haptic pulse on this controller
+        * and axis combination for 5ms. */
+        virtual void TriggerHapticPulse( vr::TrackedDeviceIndex_t unControllerDeviceIndex, uint32_t unAxisId, unsigned short usDurationMicroSec ) = 0;
+
+        /** returns the name of an EVRButtonId enum value */
+        virtual const char *GetButtonIdNameFromEnum( EVRButtonId eButtonId ) = 0;
+
+        /** returns the name of an EVRControllerAxisType enum value */
+        virtual const char *GetControllerAxisTypeNameFromEnum( EVRControllerAxisType eAxisType ) = 0;
+
+        /** Tells OpenVR that this process wants exclusive access to controller button states and button events. Other apps will be notified that 
+        * they have lost input focus with a VREvent_InputFocusCaptured event. Returns false if input focus could not be captured for
+        * some reason. */
+        virtual bool CaptureInputFocus() = 0;
+
+        /** Tells OpenVR that this process no longer wants exclusive access to button states and button events. Other apps will be notified 
+        * that input focus has been released with a VREvent_InputFocusReleased event. */
+        virtual void ReleaseInputFocus() = 0;
+
+        /** Returns true if input focus is captured by another process. */
+        virtual bool IsInputFocusCapturedByAnotherProcess() = 0;
+
+        // ------------------------------------
+        // Debug Methods
+        // ------------------------------------
+
+        /** Sends a request to the driver for the specified device and returns the response. The maximum response size is 32k,
+        * but this method can be called with a smaller buffer. If the response exceeds the size of the buffer, it is truncated. 
+        * The size of the response including its terminating null is returned. */
+        virtual uint32_t DriverDebugRequest( vr::TrackedDeviceIndex_t unDeviceIndex, const char *pchRequest, char *pchResponseBuffer, uint32_t unResponseBufferSize ) = 0;
+
+        // ------------------------------------
+        // Firmware methods
+        // ------------------------------------
+        
+        /** Performs the actual firmware update if applicable. 
+         * The following events will be sent, if VRFirmwareError_None was returned: VREvent_FirmwareUpdateStarted, VREvent_FirmwareUpdateFinished 
+         * Use the properties Prop_Firmware_UpdateAvailable_Bool, Prop_Firmware_ManualUpdate_Bool, and Prop_Firmware_ManualUpdateURL_String
+         * to figure our whether a firmware update is available, and to figure out whether its a manual update 
+         * Prop_Firmware_ManualUpdateURL_String should point to an URL describing the manual update process */
+        virtual vr::EVRFirmwareError PerformFirmwareUpdate( vr::TrackedDeviceIndex_t unDeviceIndex ) = 0;
+
+        // ------------------------------------
+        // Application life cycle methods
+        // ------------------------------------
+
+        /** Call this to acknowledge to the system that VREvent_Quit has been received and that the process is exiting.
+        * This extends the timeout until the process is killed. */
+        virtual void AcknowledgeQuit_Exiting() = 0;
+
+        /** Call this to tell the system that the user is being prompted to save data. This
+        * halts the timeout and dismisses the dashboard (if it was up). Applications should be sure to actually 
+        * prompt the user to save and then exit afterward, otherwise the user will be left in a confusing state. */
+        virtual void AcknowledgeQuit_UserPrompt() = 0;
+
+};
+
+static const char * const IVRSystem_Version = "IVRSystem_015";
+
+}
+
+
+// ivrapplications.h
+namespace vr
+{
+
+        /** Used for all errors reported by the IVRApplications interface */
+        enum EVRApplicationError
+        {
+                VRApplicationError_None = 0,
+
+                VRApplicationError_AppKeyAlreadyExists = 100,   // Only one application can use any given key
+                VRApplicationError_NoManifest = 101,                    // the running application does not have a manifest
+                VRApplicationError_NoApplication = 102,                 // No application is running
+                VRApplicationError_InvalidIndex = 103,
+                VRApplicationError_UnknownApplication = 104,    // the application could not be found
+                VRApplicationError_IPCFailed = 105,                             // An IPC failure caused the request to fail
+                VRApplicationError_ApplicationAlreadyRunning = 106, 
+                VRApplicationError_InvalidManifest = 107,
+                VRApplicationError_InvalidApplication = 108,
+                VRApplicationError_LaunchFailed = 109,                  // the process didn't start
+                VRApplicationError_ApplicationAlreadyStarting = 110, // the system was already starting the same application
+                VRApplicationError_LaunchInProgress = 111,              // The system was already starting a different application
+                VRApplicationError_OldApplicationQuitting = 112, 
+                VRApplicationError_TransitionAborted = 113,
+                VRApplicationError_IsTemplate = 114, // error when you try to call LaunchApplication() on a template type app (use LaunchTemplateApplication)
+
+                VRApplicationError_BufferTooSmall = 200,                // The provided buffer was too small to fit the requested data
+                VRApplicationError_PropertyNotSet = 201,                // The requested property was not set
+                VRApplicationError_UnknownProperty = 202,
+                VRApplicationError_InvalidParameter = 203,
+        };
+
+        /** The maximum length of an application key */
+        static const uint32_t k_unMaxApplicationKeyLength = 128;
+
+        /** these are the properties available on applications. */
+        enum EVRApplicationProperty
+        {
+                VRApplicationProperty_Name_String                               = 0,
+
+                VRApplicationProperty_LaunchType_String                 = 11,
+                VRApplicationProperty_WorkingDirectory_String   = 12,
+                VRApplicationProperty_BinaryPath_String                 = 13,
+                VRApplicationProperty_Arguments_String                  = 14,
+                VRApplicationProperty_URL_String                                = 15,
+
+                VRApplicationProperty_Description_String                = 50,
+                VRApplicationProperty_NewsURL_String                    = 51,
+                VRApplicationProperty_ImagePath_String                  = 52,
+                VRApplicationProperty_Source_String                             = 53,
+
+                VRApplicationProperty_IsDashboardOverlay_Bool   = 60,
+                VRApplicationProperty_IsTemplate_Bool                   = 61,
+                VRApplicationProperty_IsInstanced_Bool                  = 62,
+                VRApplicationProperty_IsInternal_Bool                   = 63,
+
+                VRApplicationProperty_LastLaunchTime_Uint64             = 70,
+        };
+
+        /** These are states the scene application startup process will go through. */
+        enum EVRApplicationTransitionState
+        {
+                VRApplicationTransition_None = 0,
+
+                VRApplicationTransition_OldAppQuitSent = 10,
+                VRApplicationTransition_WaitingForExternalLaunch = 11,
+                
+                VRApplicationTransition_NewAppLaunched = 20,
+        };
+
+        struct AppOverrideKeys_t
+        {
+                const char *pchKey;
+                const char *pchValue;
+        };
+
+        /** Currently recognized mime types */
+        static const char * const k_pch_MimeType_HomeApp                = "vr/home";
+        static const char * const k_pch_MimeType_GameTheater    = "vr/game_theater";
+
+        class IVRApplications
+        {
+        public:
+
+                // ---------------  Application management  --------------- //
+
+                /** Adds an application manifest to the list to load when building the list of installed applications. 
+                * Temporary manifests are not automatically loaded */
+                virtual EVRApplicationError AddApplicationManifest( const char *pchApplicationManifestFullPath, bool bTemporary = false ) = 0;
+
+                /** Removes an application manifest from the list to load when building the list of installed applications. */
+                virtual EVRApplicationError RemoveApplicationManifest( const char *pchApplicationManifestFullPath ) = 0;
+
+                /** Returns true if an application is installed */
+                virtual bool IsApplicationInstalled( const char *pchAppKey ) = 0;
+
+                /** Returns the number of applications available in the list */
+                virtual uint32_t GetApplicationCount() = 0;
+
+                /** Returns the key of the specified application. The index is at least 0 and is less than the return 
+                * value of GetApplicationCount(). The buffer should be at least k_unMaxApplicationKeyLength in order to 
+                * fit the key. */
+                virtual EVRApplicationError GetApplicationKeyByIndex( uint32_t unApplicationIndex, VR_OUT_STRING() char *pchAppKeyBuffer, uint32_t unAppKeyBufferLen ) = 0;
+
+                /** Returns the key of the application for the specified Process Id. The buffer should be at least 
+                * k_unMaxApplicationKeyLength in order to fit the key. */
+                virtual EVRApplicationError GetApplicationKeyByProcessId( uint32_t unProcessId, char *pchAppKeyBuffer, uint32_t unAppKeyBufferLen ) = 0;
+
+                /** Launches the application. The existing scene application will exit and then the new application will start.
+                * This call is not valid for dashboard overlay applications. */
+                virtual EVRApplicationError LaunchApplication( const char *pchAppKey ) = 0;
+
+                /** Launches an instance of an application of type template, with its app key being pchNewAppKey (which must be unique) and optionally override sections
+                * from the manifest file via AppOverrideKeys_t
+                */
+                virtual EVRApplicationError LaunchTemplateApplication( const char *pchTemplateAppKey, const char *pchNewAppKey, VR_ARRAY_COUNT( unKeys ) const AppOverrideKeys_t *pKeys, uint32_t unKeys ) = 0;
+
+                /** launches the application currently associated with this mime type and passes it the option args, typically the filename or object name of the item being launched */
+                virtual vr::EVRApplicationError LaunchApplicationFromMimeType( const char *pchMimeType, const char *pchArgs ) = 0;
+
+                /** Launches the dashboard overlay application if it is not already running. This call is only valid for 
+                * dashboard overlay applications. */
+                virtual EVRApplicationError LaunchDashboardOverlay( const char *pchAppKey ) = 0;
+
+                /** Cancel a pending launch for an application */
+                virtual bool CancelApplicationLaunch( const char *pchAppKey ) = 0;
+
+                /** Identifies a running application. OpenVR can't always tell which process started in response
+                * to a URL. This function allows a URL handler (or the process itself) to identify the app key 
+                * for the now running application. Passing a process ID of 0 identifies the calling process. 
+                * The application must be one that's known to the system via a call to AddApplicationManifest. */
+                virtual EVRApplicationError IdentifyApplication( uint32_t unProcessId, const char *pchAppKey ) = 0;
+
+                /** Returns the process ID for an application. Return 0 if the application was not found or is not running. */
+                virtual uint32_t GetApplicationProcessId( const char *pchAppKey ) = 0;
+
+                /** Returns a string for an applications error */
+                virtual const char *GetApplicationsErrorNameFromEnum( EVRApplicationError error ) = 0;
+
+                // ---------------  Application properties  --------------- //
+
+                /** Returns a value for an application property. The required buffer size to fit this value will be returned. */
+                virtual uint32_t GetApplicationPropertyString( const char *pchAppKey, EVRApplicationProperty eProperty, VR_OUT_STRING() char *pchPropertyValueBuffer, uint32_t unPropertyValueBufferLen, EVRApplicationError *peError = nullptr ) = 0;
+
+                /** Returns a bool value for an application property. Returns false in all error cases. */
+                virtual bool GetApplicationPropertyBool( const char *pchAppKey, EVRApplicationProperty eProperty, EVRApplicationError *peError = nullptr ) = 0;
+
+                /** Returns a uint64 value for an application property. Returns 0 in all error cases. */
+                virtual uint64_t GetApplicationPropertyUint64( const char *pchAppKey, EVRApplicationProperty eProperty, EVRApplicationError *peError = nullptr ) = 0;
+
+                /** Sets the application auto-launch flag. This is only valid for applications which return true for VRApplicationProperty_IsDashboardOverlay_Bool. */
+                virtual EVRApplicationError SetApplicationAutoLaunch( const char *pchAppKey, bool bAutoLaunch ) = 0;
+
+                /** Gets the application auto-launch flag. This is only valid for applications which return true for VRApplicationProperty_IsDashboardOverlay_Bool. */
+                virtual bool GetApplicationAutoLaunch( const char *pchAppKey ) = 0;
+
+                /** Adds this mime-type to the list of supported mime types for this application*/
+                virtual EVRApplicationError SetDefaultApplicationForMimeType( const char *pchAppKey, const char *pchMimeType ) = 0;
+
+                /** return the app key that will open this mime type */
+                virtual bool GetDefaultApplicationForMimeType( const char *pchMimeType, char *pchAppKeyBuffer, uint32_t unAppKeyBufferLen ) = 0;
+
+                /** Get the list of supported mime types for this application, comma-delimited */
+                virtual bool GetApplicationSupportedMimeTypes( const char *pchAppKey, char *pchMimeTypesBuffer, uint32_t unMimeTypesBuffer ) = 0;
+
+                /** Get the list of app-keys that support this mime type, comma-delimited, the return value is number of bytes you need to return the full string */
+                virtual uint32_t GetApplicationsThatSupportMimeType( const char *pchMimeType, char *pchAppKeysThatSupportBuffer, uint32_t unAppKeysThatSupportBuffer ) = 0;
+
+                /** Get the args list from an app launch that had the process already running, you call this when you get a VREvent_ApplicationMimeTypeLoad */
+                virtual uint32_t GetApplicationLaunchArguments( uint32_t unHandle, char *pchArgs, uint32_t unArgs ) = 0;
+
+                // ---------------  Transition methods --------------- //
+
+                /** Returns the app key for the application that is starting up */
+                virtual EVRApplicationError GetStartingApplication( char *pchAppKeyBuffer, uint32_t unAppKeyBufferLen ) = 0;
+
+                /** Returns the application transition state */
+                virtual EVRApplicationTransitionState GetTransitionState() = 0;
+
+                /** Returns errors that would prevent the specified application from launching immediately. Calling this function will
+                * cause the current scene application to quit, so only call it when you are actually about to launch something else.
+                * What the caller should do about these failures depends on the failure:
+                *   VRApplicationError_OldApplicationQuitting - An existing application has been told to quit. Wait for a VREvent_ProcessQuit
+                *                                               and try again.
+                *   VRApplicationError_ApplicationAlreadyStarting - This application is already starting. This is a permanent failure.
+                *   VRApplicationError_LaunchInProgress       - A different application is already starting. This is a permanent failure.
+                *   VRApplicationError_None                   - Go ahead and launch. Everything is clear.
+                */
+                virtual EVRApplicationError PerformApplicationPrelaunchCheck( const char *pchAppKey ) = 0;
+
+                /** Returns a string for an application transition state */
+                virtual const char *GetApplicationsTransitionStateNameFromEnum( EVRApplicationTransitionState state ) = 0;
+
+                /** Returns true if the outgoing scene app has requested a save prompt before exiting */
+                virtual bool IsQuitUserPromptRequested() = 0;
+
+                /** Starts a subprocess within the calling application. This
+                * suppresses all application transition UI and automatically identifies the new executable 
+                * as part of the same application. On success the calling process should exit immediately. 
+                * If working directory is NULL or "" the directory portion of the binary path will be 
+                * the working directory. */
+                virtual EVRApplicationError LaunchInternalProcess( const char *pchBinaryPath, const char *pchArguments, const char *pchWorkingDirectory ) = 0;
+
+                /** Returns the current scene process ID according to the application system. A scene process will get scene
+                * focus once it starts rendering, but it will appear here once it calls VR_Init with the Scene application
+                * type. */
+                virtual uint32_t GetCurrentSceneProcessId() = 0;
+        };
+
+        static const char * const IVRApplications_Version = "IVRApplications_006";
+
+} // namespace vr
+
+// ivrsettings.h
+namespace vr
+{
+        enum EVRSettingsError
+        {
+                VRSettingsError_None = 0,
+                VRSettingsError_IPCFailed = 1,
+                VRSettingsError_WriteFailed = 2,
+                VRSettingsError_ReadFailed = 3,
+                VRSettingsError_JsonParseFailed = 4,
+                VRSettingsError_UnsetSettingHasNoDefault = 5, // This will be returned if the setting does not appear in the appropriate default file and has not been set
+        };
+
+        // The maximum length of a settings key
+        static const uint32_t k_unMaxSettingsKeyLength = 128;
+
+        class IVRSettings
+        {
+        public:
+                virtual const char *GetSettingsErrorNameFromEnum( EVRSettingsError eError ) = 0;
+
+                // Returns true if file sync occurred (force or settings dirty)
+                virtual bool Sync( bool bForce = false, EVRSettingsError *peError = nullptr ) = 0;
+
+                virtual void SetBool( const char *pchSection, const char *pchSettingsKey, bool bValue, EVRSettingsError *peError = nullptr ) = 0;
+                virtual void SetInt32( const char *pchSection, const char *pchSettingsKey, int32_t nValue, EVRSettingsError *peError = nullptr ) = 0;
+                virtual void SetFloat( const char *pchSection, const char *pchSettingsKey, float flValue, EVRSettingsError *peError = nullptr ) = 0;
+                virtual void SetString( const char *pchSection, const char *pchSettingsKey, const char *pchValue, EVRSettingsError *peError = nullptr ) = 0;
+
+                // Users of the system need to provide a proper default in default.vrsettings in the resources/settings/ directory
+                // of either the runtime or the driver_xxx directory. Otherwise the default will be false, 0, 0.0 or ""
+                virtual bool GetBool( const char *pchSection, const char *pchSettingsKey, EVRSettingsError *peError = nullptr ) = 0;
+                virtual int32_t GetInt32( const char *pchSection, const char *pchSettingsKey, EVRSettingsError *peError = nullptr ) = 0;
+                virtual float GetFloat( const char *pchSection, const char *pchSettingsKey, EVRSettingsError *peError = nullptr ) = 0;
+                virtual void GetString( const char *pchSection, const char *pchSettingsKey, VR_OUT_STRING() char *pchValue, uint32_t unValueLen, EVRSettingsError *peError = nullptr ) = 0;
+
+                virtual void RemoveSection( const char *pchSection, EVRSettingsError *peError = nullptr ) = 0;
+                virtual void RemoveKeyInSection( const char *pchSection, const char *pchSettingsKey, EVRSettingsError *peError = nullptr ) = 0;
+        };
+
+        //-----------------------------------------------------------------------------
+        static const char * const IVRSettings_Version = "IVRSettings_002";
+
+        //-----------------------------------------------------------------------------
+        // steamvr keys
+        static const char * const k_pch_SteamVR_Section = "steamvr";
+        static const char * const k_pch_SteamVR_RequireHmd_String = "requireHmd";
+        static const char * const k_pch_SteamVR_ForcedDriverKey_String = "forcedDriver";
+        static const char * const k_pch_SteamVR_ForcedHmdKey_String = "forcedHmd";
+        static const char * const k_pch_SteamVR_DisplayDebug_Bool = "displayDebug";
+        static const char * const k_pch_SteamVR_DebugProcessPipe_String = "debugProcessPipe";
+        static const char * const k_pch_SteamVR_EnableDistortion_Bool = "enableDistortion";
+        static const char * const k_pch_SteamVR_DisplayDebugX_Int32 = "displayDebugX";
+        static const char * const k_pch_SteamVR_DisplayDebugY_Int32 = "displayDebugY";
+        static const char * const k_pch_SteamVR_SendSystemButtonToAllApps_Bool= "sendSystemButtonToAllApps";
+        static const char * const k_pch_SteamVR_LogLevel_Int32 = "loglevel";
+        static const char * const k_pch_SteamVR_IPD_Float = "ipd";
+        static const char * const k_pch_SteamVR_Background_String = "background";
+        static const char * const k_pch_SteamVR_BackgroundUseDomeProjection_Bool = "backgroundUseDomeProjection";
+        static const char * const k_pch_SteamVR_BackgroundCameraHeight_Float = "backgroundCameraHeight";
+        static const char * const k_pch_SteamVR_BackgroundDomeRadius_Float = "backgroundDomeRadius";
+        static const char * const k_pch_SteamVR_GridColor_String = "gridColor";
+        static const char * const k_pch_SteamVR_PlayAreaColor_String = "playAreaColor";
+        static const char * const k_pch_SteamVR_ShowStage_Bool = "showStage";
+        static const char * const k_pch_SteamVR_ActivateMultipleDrivers_Bool = "activateMultipleDrivers";
+        static const char * const k_pch_SteamVR_DirectMode_Bool = "directMode";
+        static const char * const k_pch_SteamVR_DirectModeEdidVid_Int32 = "directModeEdidVid";
+        static const char * const k_pch_SteamVR_DirectModeEdidPid_Int32 = "directModeEdidPid";
+        static const char * const k_pch_SteamVR_UsingSpeakers_Bool = "usingSpeakers";
+        static const char * const k_pch_SteamVR_SpeakersForwardYawOffsetDegrees_Float = "speakersForwardYawOffsetDegrees";
+        static const char * const k_pch_SteamVR_BaseStationPowerManagement_Bool = "basestationPowerManagement";
+        static const char * const k_pch_SteamVR_NeverKillProcesses_Bool = "neverKillProcesses";
+        static const char * const k_pch_SteamVR_RenderTargetMultiplier_Float = "renderTargetMultiplier";
+        static const char * const k_pch_SteamVR_AllowAsyncReprojection_Bool = "allowAsyncReprojection";
+        static const char * const k_pch_SteamVR_AllowReprojection_Bool = "allowInterleavedReprojection";
+        static const char * const k_pch_SteamVR_ForceReprojection_Bool = "forceReprojection";
+        static const char * const k_pch_SteamVR_ForceFadeOnBadTracking_Bool = "forceFadeOnBadTracking";
+        static const char * const k_pch_SteamVR_DefaultMirrorView_Int32 = "defaultMirrorView";
+        static const char * const k_pch_SteamVR_ShowMirrorView_Bool = "showMirrorView";
+        static const char * const k_pch_SteamVR_MirrorViewGeometry_String = "mirrorViewGeometry";
+        static const char * const k_pch_SteamVR_StartMonitorFromAppLaunch = "startMonitorFromAppLaunch";
+        static const char * const k_pch_SteamVR_StartCompositorFromAppLaunch_Bool = "startCompositorFromAppLaunch";
+        static const char * const k_pch_SteamVR_StartDashboardFromAppLaunch_Bool = "startDashboardFromAppLaunch";
+        static const char * const k_pch_SteamVR_StartOverlayAppsFromDashboard_Bool = "startOverlayAppsFromDashboard";
+        static const char * const k_pch_SteamVR_EnableHomeApp = "enableHomeApp";
+        static const char * const k_pch_SteamVR_SetInitialDefaultHomeApp = "setInitialDefaultHomeApp";
+        static const char * const k_pch_SteamVR_CycleBackgroundImageTimeSec_Int32 = "CycleBackgroundImageTimeSec";
+        static const char * const k_pch_SteamVR_RetailDemo_Bool = "retailDemo";
+        static const char * const k_pch_SteamVR_IpdOffset_Float = "ipdOffset";
+
+        //-----------------------------------------------------------------------------
+        // lighthouse keys
+        static const char * const k_pch_Lighthouse_Section = "driver_lighthouse";
+        static const char * const k_pch_Lighthouse_DisableIMU_Bool = "disableimu";
+        static const char * const k_pch_Lighthouse_UseDisambiguation_String = "usedisambiguation";
+        static const char * const k_pch_Lighthouse_DisambiguationDebug_Int32 = "disambiguationdebug";
+        static const char * const k_pch_Lighthouse_PrimaryBasestation_Int32 = "primarybasestation";
+        static const char * const k_pch_Lighthouse_DBHistory_Bool = "dbhistory";
+
+        //-----------------------------------------------------------------------------
+        // null keys
+        static const char * const k_pch_Null_Section = "driver_null";
+        static const char * const k_pch_Null_SerialNumber_String = "serialNumber";
+        static const char * const k_pch_Null_ModelNumber_String = "modelNumber";
+        static const char * const k_pch_Null_WindowX_Int32 = "windowX";
+        static const char * const k_pch_Null_WindowY_Int32 = "windowY";
+        static const char * const k_pch_Null_WindowWidth_Int32 = "windowWidth";
+        static const char * const k_pch_Null_WindowHeight_Int32 = "windowHeight";
+        static const char * const k_pch_Null_RenderWidth_Int32 = "renderWidth";
+        static const char * const k_pch_Null_RenderHeight_Int32 = "renderHeight";
+        static const char * const k_pch_Null_SecondsFromVsyncToPhotons_Float = "secondsFromVsyncToPhotons";
+        static const char * const k_pch_Null_DisplayFrequency_Float = "displayFrequency";
+
+        //-----------------------------------------------------------------------------
+        // user interface keys
+        static const char * const k_pch_UserInterface_Section = "userinterface";
+        static const char * const k_pch_UserInterface_StatusAlwaysOnTop_Bool = "StatusAlwaysOnTop";
+        static const char * const k_pch_UserInterface_MinimizeToTray_Bool = "MinimizeToTray";
+        static const char * const k_pch_UserInterface_Screenshots_Bool = "screenshots";
+        static const char * const k_pch_UserInterface_ScreenshotType_Int = "screenshotType";
+
+        //-----------------------------------------------------------------------------
+        // notification keys
+        static const char * const k_pch_Notifications_Section = "notifications";
+        static const char * const k_pch_Notifications_DoNotDisturb_Bool = "DoNotDisturb";
+
+        //-----------------------------------------------------------------------------
+        // keyboard keys
+        static const char * const k_pch_Keyboard_Section = "keyboard";
+        static const char * const k_pch_Keyboard_TutorialCompletions = "TutorialCompletions";
+        static const char * const k_pch_Keyboard_ScaleX = "ScaleX";
+        static const char * const k_pch_Keyboard_ScaleY = "ScaleY";
+        static const char * const k_pch_Keyboard_OffsetLeftX = "OffsetLeftX";
+        static const char * const k_pch_Keyboard_OffsetRightX = "OffsetRightX";
+        static const char * const k_pch_Keyboard_OffsetY = "OffsetY";
+        static const char * const k_pch_Keyboard_Smoothing = "Smoothing";
+
+        //-----------------------------------------------------------------------------
+        // perf keys
+        static const char * const k_pch_Perf_Section = "perfcheck";
+        static const char * const k_pch_Perf_HeuristicActive_Bool = "heuristicActive";
+        static const char * const k_pch_Perf_NotifyInHMD_Bool = "warnInHMD";
+        static const char * const k_pch_Perf_NotifyOnlyOnce_Bool = "warnOnlyOnce";
+        static const char * const k_pch_Perf_AllowTimingStore_Bool = "allowTimingStore";
+        static const char * const k_pch_Perf_SaveTimingsOnExit_Bool = "saveTimingsOnExit";
+        static const char * const k_pch_Perf_TestData_Float = "perfTestData";
+
+        //-----------------------------------------------------------------------------
+        // collision bounds keys
+        static const char * const k_pch_CollisionBounds_Section = "collisionBounds";
+        static const char * const k_pch_CollisionBounds_Style_Int32 = "CollisionBoundsStyle";
+        static const char * const k_pch_CollisionBounds_GroundPerimeterOn_Bool = "CollisionBoundsGroundPerimeterOn";
+        static const char * const k_pch_CollisionBounds_CenterMarkerOn_Bool = "CollisionBoundsCenterMarkerOn";
+        static const char * const k_pch_CollisionBounds_PlaySpaceOn_Bool = "CollisionBoundsPlaySpaceOn";
+        static const char * const k_pch_CollisionBounds_FadeDistance_Float = "CollisionBoundsFadeDistance";
+        static const char * const k_pch_CollisionBounds_ColorGammaR_Int32 = "CollisionBoundsColorGammaR";
+        static const char * const k_pch_CollisionBounds_ColorGammaG_Int32 = "CollisionBoundsColorGammaG";
+        static const char * const k_pch_CollisionBounds_ColorGammaB_Int32 = "CollisionBoundsColorGammaB";
+        static const char * const k_pch_CollisionBounds_ColorGammaA_Int32 = "CollisionBoundsColorGammaA";
+
+        //-----------------------------------------------------------------------------
+        // camera keys
+        static const char * const k_pch_Camera_Section = "camera";
+        static const char * const k_pch_Camera_EnableCamera_Bool = "enableCamera";
+        static const char * const k_pch_Camera_EnableCameraInDashboard_Bool = "enableCameraInDashboard";
+        static const char * const k_pch_Camera_EnableCameraForCollisionBounds_Bool = "enableCameraForCollisionBounds";
+        static const char * const k_pch_Camera_EnableCameraForRoomView_Bool = "enableCameraForRoomView";
+        static const char * const k_pch_Camera_BoundsColorGammaR_Int32 = "cameraBoundsColorGammaR";
+        static const char * const k_pch_Camera_BoundsColorGammaG_Int32 = "cameraBoundsColorGammaG";
+        static const char * const k_pch_Camera_BoundsColorGammaB_Int32 = "cameraBoundsColorGammaB";
+        static const char * const k_pch_Camera_BoundsColorGammaA_Int32 = "cameraBoundsColorGammaA";
+        static const char * const k_pch_Camera_BoundsStrength_Int32 = "cameraBoundsStrength";
+
+        //-----------------------------------------------------------------------------
+        // audio keys
+        static const char * const k_pch_audio_Section = "audio";
+        static const char * const k_pch_audio_OnPlaybackDevice_String = "onPlaybackDevice";
+        static const char * const k_pch_audio_OnRecordDevice_String = "onRecordDevice";
+        static const char * const k_pch_audio_OnPlaybackMirrorDevice_String = "onPlaybackMirrorDevice";
+        static const char * const k_pch_audio_OffPlaybackDevice_String = "offPlaybackDevice";
+        static const char * const k_pch_audio_OffRecordDevice_String = "offRecordDevice";
+        static const char * const k_pch_audio_VIVEHDMIGain = "viveHDMIGain";
+
+        //-----------------------------------------------------------------------------
+        // power management keys
+        static const char * const k_pch_Power_Section = "power";
+        static const char * const k_pch_Power_PowerOffOnExit_Bool = "powerOffOnExit";
+        static const char * const k_pch_Power_TurnOffScreensTimeout_Float = "turnOffScreensTimeout";
+        static const char * const k_pch_Power_TurnOffControllersTimeout_Float = "turnOffControllersTimeout";
+        static const char * const k_pch_Power_ReturnToWatchdogTimeout_Float = "returnToWatchdogTimeout";
+        static const char * const k_pch_Power_AutoLaunchSteamVROnButtonPress = "autoLaunchSteamVROnButtonPress";
+
+        //-----------------------------------------------------------------------------
+        // dashboard keys
+        static const char * const k_pch_Dashboard_Section = "dashboard";
+        static const char * const k_pch_Dashboard_EnableDashboard_Bool = "enableDashboard";
+        static const char * const k_pch_Dashboard_ArcadeMode_Bool = "arcadeMode";
+
+        //-----------------------------------------------------------------------------
+        // model skin keys
+        static const char * const k_pch_modelskin_Section = "modelskins";
+
+        //-----------------------------------------------------------------------------
+        // driver keys - These could be checked in any driver_<name> section
+        static const char * const k_pch_Driver_Enable_Bool = "enable";
+
+} // namespace vr
+
+// ivrchaperone.h
+namespace vr
+{
+
+#if defined(__linux__) || defined(__APPLE__) 
+        // The 32-bit version of gcc has the alignment requirement for uint64 and double set to
+        // 4 meaning that even with #pragma pack(8) these types will only be four-byte aligned.
+        // The 64-bit version of gcc has the alignment requirement for these types set to
+        // 8 meaning that unless we use #pragma pack(4) our structures will get bigger.
+        // The 64-bit structure packing has to match the 32-bit structure packing for each platform.
+        #pragma pack( push, 4 )
+#else
+        #pragma pack( push, 8 )
+#endif
+
+enum ChaperoneCalibrationState
+{
+        // OK!
+        ChaperoneCalibrationState_OK = 1,                                                                       // Chaperone is fully calibrated and working correctly
+
+        // Warnings
+        ChaperoneCalibrationState_Warning = 100,
+        ChaperoneCalibrationState_Warning_BaseStationMayHaveMoved = 101,        // A base station thinks that it might have moved
+        ChaperoneCalibrationState_Warning_BaseStationRemoved = 102,                     // There are less base stations than when calibrated
+        ChaperoneCalibrationState_Warning_SeatedBoundsInvalid = 103,            // Seated bounds haven't been calibrated for the current tracking center
+
+        // Errors
+        ChaperoneCalibrationState_Error = 200,                                                          // The UniverseID is invalid
+        ChaperoneCalibrationState_Error_BaseStationUninitialized = 201,         // Tracking center hasn't be calibrated for at least one of the base stations
+        ChaperoneCalibrationState_Error_BaseStationConflict = 202,                      // Tracking center is calibrated, but base stations disagree on the tracking space
+        ChaperoneCalibrationState_Error_PlayAreaInvalid = 203,                          // Play Area hasn't been calibrated for the current tracking center
+        ChaperoneCalibrationState_Error_CollisionBoundsInvalid = 204,           // Collision Bounds haven't been calibrated for the current tracking center
+};
+
+
+/** HIGH LEVEL TRACKING SPACE ASSUMPTIONS:
+* 0,0,0 is the preferred standing area center.
+* 0Y is the floor height.
+* -Z is the preferred forward facing direction. */
+class IVRChaperone
+{
+public:
+
+        /** Get the current state of Chaperone calibration. This state can change at any time during a session due to physical base station changes. **/
+        virtual ChaperoneCalibrationState GetCalibrationState() = 0;
+
+        /** Returns the width and depth of the Play Area (formerly named Soft Bounds) in X and Z. 
+        * Tracking space center (0,0,0) is the center of the Play Area. **/
+        virtual bool GetPlayAreaSize( float *pSizeX, float *pSizeZ ) = 0;
+
+        /** Returns the 4 corner positions of the Play Area (formerly named Soft Bounds).
+        * Corners are in counter-clockwise order.
+        * Standing center (0,0,0) is the center of the Play Area.
+        * It's a rectangle.
+        * 2 sides are parallel to the X axis and 2 sides are parallel to the Z axis.
+        * Height of every corner is 0Y (on the floor). **/
+        virtual bool GetPlayAreaRect( HmdQuad_t *rect ) = 0;
+
+        /** Reload Chaperone data from the .vrchap file on disk. */
+        virtual void ReloadInfo( void ) = 0;
+
+        /** Optionally give the chaperone system a hit about the color and brightness in the scene **/
+        virtual void SetSceneColor( HmdColor_t color ) = 0;
+
+        /** Get the current chaperone bounds draw color and brightness **/
+        virtual void GetBoundsColor( HmdColor_t *pOutputColorArray, int nNumOutputColors, float flCollisionBoundsFadeDistance, HmdColor_t *pOutputCameraColor ) = 0;
+
+        /** Determine whether the bounds are showing right now **/
+        virtual bool AreBoundsVisible() = 0;
+
+        /** Force the bounds to show, mostly for utilities **/
+        virtual void ForceBoundsVisible( bool bForce ) = 0;
+};
+
+static const char * const IVRChaperone_Version = "IVRChaperone_003";
+
+#pragma pack( pop )
+
+}
+
+// ivrchaperonesetup.h
+namespace vr
+{
+
+enum EChaperoneConfigFile
+{
+        EChaperoneConfigFile_Live = 1,          // The live chaperone config, used by most applications and games
+        EChaperoneConfigFile_Temp = 2,          // The temporary chaperone config, used to live-preview collision bounds in room setup
+};
+
+enum EChaperoneImportFlags
+{
+        EChaperoneImport_BoundsOnly = 0x0001,
+};
+
+/** Manages the working copy of the chaperone info. By default this will be the same as the 
+* live copy. Any changes made with this interface will stay in the working copy until 
+* CommitWorkingCopy() is called, at which point the working copy and the live copy will be 
+* the same again. */
+class IVRChaperoneSetup
+{
+public:
+
+        /** Saves the current working copy to disk */
+        virtual bool CommitWorkingCopy( EChaperoneConfigFile configFile ) = 0;
+
+        /** Reverts the working copy to match the live chaperone calibration.
+        * To modify existing data this MUST be do WHILE getting a non-error ChaperoneCalibrationStatus.
+        * Only after this should you do gets and sets on the existing data. */
+        virtual void RevertWorkingCopy() = 0;
+
+        /** Returns the width and depth of the Play Area (formerly named Soft Bounds) in X and Z from the working copy.
+        * Tracking space center (0,0,0) is the center of the Play Area. */
+        virtual bool GetWorkingPlayAreaSize( float *pSizeX, float *pSizeZ ) = 0;
+
+        /** Returns the 4 corner positions of the Play Area (formerly named Soft Bounds) from the working copy.
+        * Corners are in clockwise order.
+        * Tracking space center (0,0,0) is the center of the Play Area.
+        * It's a rectangle.
+        * 2 sides are parallel to the X axis and 2 sides are parallel to the Z axis.
+        * Height of every corner is 0Y (on the floor). **/
+        virtual bool GetWorkingPlayAreaRect( HmdQuad_t *rect ) = 0;
+
+        /** Returns the number of Quads if the buffer points to null. Otherwise it returns Quads 
+        * into the buffer up to the max specified from the working copy. */
+        virtual bool GetWorkingCollisionBoundsInfo( VR_OUT_ARRAY_COUNT(punQuadsCount) HmdQuad_t *pQuadsBuffer, uint32_t* punQuadsCount ) = 0;
+
+        /** Returns the number of Quads if the buffer points to null. Otherwise it returns Quads 
+        * into the buffer up to the max specified. */
+        virtual bool GetLiveCollisionBoundsInfo( VR_OUT_ARRAY_COUNT(punQuadsCount) HmdQuad_t *pQuadsBuffer, uint32_t* punQuadsCount ) = 0;
+
+        /** Returns the preferred seated position from the working copy. */
+        virtual bool GetWorkingSeatedZeroPoseToRawTrackingPose( HmdMatrix34_t *pmatSeatedZeroPoseToRawTrackingPose ) = 0;
+
+        /** Returns the standing origin from the working copy. */
+        virtual bool GetWorkingStandingZeroPoseToRawTrackingPose( HmdMatrix34_t *pmatStandingZeroPoseToRawTrackingPose ) = 0;
+
+        /** Sets the Play Area in the working copy. */
+        virtual void SetWorkingPlayAreaSize( float sizeX, float sizeZ ) = 0;
+
+        /** Sets the Collision Bounds in the working copy. */
+        virtual void SetWorkingCollisionBoundsInfo( VR_ARRAY_COUNT(unQuadsCount) HmdQuad_t *pQuadsBuffer, uint32_t unQuadsCount ) = 0;
+
+        /** Sets the preferred seated position in the working copy. */
+        virtual void SetWorkingSeatedZeroPoseToRawTrackingPose( const HmdMatrix34_t *pMatSeatedZeroPoseToRawTrackingPose ) = 0;
+
+        /** Sets the preferred standing position in the working copy. */
+        virtual void SetWorkingStandingZeroPoseToRawTrackingPose( const HmdMatrix34_t *pMatStandingZeroPoseToRawTrackingPose ) = 0;
+
+        /** Tear everything down and reload it from the file on disk */
+        virtual void ReloadFromDisk( EChaperoneConfigFile configFile ) = 0;
+
+        /** Returns the preferred seated position. */
+        virtual bool GetLiveSeatedZeroPoseToRawTrackingPose( HmdMatrix34_t *pmatSeatedZeroPoseToRawTrackingPose ) = 0;
+
+        virtual void SetWorkingCollisionBoundsTagsInfo( VR_ARRAY_COUNT(unTagCount) uint8_t *pTagsBuffer, uint32_t unTagCount ) = 0;
+        virtual bool GetLiveCollisionBoundsTagsInfo( VR_OUT_ARRAY_COUNT(punTagCount) uint8_t *pTagsBuffer, uint32_t *punTagCount ) = 0;
+
+        virtual bool SetWorkingPhysicalBoundsInfo( VR_ARRAY_COUNT(unQuadsCount) HmdQuad_t *pQuadsBuffer, uint32_t unQuadsCount ) = 0;
+        virtual bool GetLivePhysicalBoundsInfo( VR_OUT_ARRAY_COUNT(punQuadsCount) HmdQuad_t *pQuadsBuffer, uint32_t* punQuadsCount ) = 0;
+
+        virtual bool ExportLiveToBuffer( VR_OUT_STRING() char *pBuffer, uint32_t *pnBufferLength ) = 0;
+        virtual bool ImportFromBufferToWorking( const char *pBuffer, uint32_t nImportFlags ) = 0;
+};
+
+static const char * const IVRChaperoneSetup_Version = "IVRChaperoneSetup_005";
+
+
+}
+
+// ivrcompositor.h
+namespace vr
+{
+
+#if defined(__linux__) || defined(__APPLE__) 
+        // The 32-bit version of gcc has the alignment requirement for uint64 and double set to
+        // 4 meaning that even with #pragma pack(8) these types will only be four-byte aligned.
+        // The 64-bit version of gcc has the alignment requirement for these types set to
+        // 8 meaning that unless we use #pragma pack(4) our structures will get bigger.
+        // The 64-bit structure packing has to match the 32-bit structure packing for each platform.
+        #pragma pack( push, 4 )
+#else
+        #pragma pack( push, 8 )
+#endif
+
+/** Errors that can occur with the VR compositor */
+enum EVRCompositorError
+{
+        VRCompositorError_None                                          = 0,
+        VRCompositorError_RequestFailed                         = 1,
+        VRCompositorError_IncompatibleVersion           = 100,
+        VRCompositorError_DoNotHaveFocus                        = 101,
+        VRCompositorError_InvalidTexture                        = 102,
+        VRCompositorError_IsNotSceneApplication         = 103,
+        VRCompositorError_TextureIsOnWrongDevice        = 104,
+        VRCompositorError_TextureUsesUnsupportedFormat = 105,
+        VRCompositorError_SharedTexturesNotSupported = 106,
+        VRCompositorError_IndexOutOfRange                       = 107,
+        VRCompositorError_AlreadySubmitted                      = 108,
+};
+
+const uint32_t VRCompositor_ReprojectionReason_Cpu = 0x01;
+const uint32_t VRCompositor_ReprojectionReason_Gpu = 0x02;
+const uint32_t VRCompositor_ReprojectionAsync      = 0x04;      // This flag indicates the async reprojection mode is active,
+                                                                                                                        // but does not indicate if reprojection actually happened or not.
+                                                                                                                        // Use the ReprojectionReason flags above to check if reprojection
+                                                                                                                        // was actually applied (i.e. scene texture was reused).
+                                                                                                                        // NumFramePresents > 1 also indicates the scene texture was reused,
+                                                                                                                        // and also the number of times that it was presented in total.
+
+/** Provides a single frame's timing information to the app */
+struct Compositor_FrameTiming
+{
+        uint32_t m_nSize; // Set to sizeof( Compositor_FrameTiming )
+        uint32_t m_nFrameIndex;
+        uint32_t m_nNumFramePresents; // number of times this frame was presented
+        uint32_t m_nNumMisPresented; // number of times this frame was presented on a vsync other than it was originally predicted to
+        uint32_t m_nNumDroppedFrames; // number of additional times previous frame was scanned out
+        uint32_t m_nReprojectionFlags;
+
+        /** Absolute time reference for comparing frames.  This aligns with the vsync that running start is relative to. */
+        double m_flSystemTimeInSeconds;
+
+        /** These times may include work from other processes due to OS scheduling.
+        * The fewer packets of work these are broken up into, the less likely this will happen.
+        * GPU work can be broken up by calling Flush.  This can sometimes be useful to get the GPU started
+        * processing that work earlier in the frame. */
+        float m_flPreSubmitGpuMs; // time spent rendering the scene (gpu work submitted between WaitGetPoses and second Submit)
+        float m_flPostSubmitGpuMs; // additional time spent rendering by application (e.g. companion window)
+        float m_flTotalRenderGpuMs; // time between work submitted immediately after present (ideally vsync) until the end of compositor submitted work
+        float m_flCompositorRenderGpuMs; // time spend performing distortion correction, rendering chaperone, overlays, etc.
+        float m_flCompositorRenderCpuMs; // time spent on cpu submitting the above work for this frame
+        float m_flCompositorIdleCpuMs; // time spent waiting for running start (application could have used this much more time)
+
+        /** Miscellaneous measured intervals. */
+        float m_flClientFrameIntervalMs; // time between calls to WaitGetPoses
+        float m_flPresentCallCpuMs; // time blocked on call to present (usually 0.0, but can go long)
+        float m_flWaitForPresentCpuMs; // time spent spin-waiting for frame index to change (not near-zero indicates wait object failure)
+        float m_flSubmitFrameMs; // time spent in IVRCompositor::Submit (not near-zero indicates driver issue)
+
+        /** The following are all relative to this frame's SystemTimeInSeconds */
+        float m_flWaitGetPosesCalledMs;
+        float m_flNewPosesReadyMs;
+        float m_flNewFrameReadyMs; // second call to IVRCompositor::Submit
+        float m_flCompositorUpdateStartMs;
+        float m_flCompositorUpdateEndMs;
+        float m_flCompositorRenderStartMs;
+
+        vr::TrackedDevicePose_t m_HmdPose; // pose used by app to render this frame
+};
+
+/** Cumulative stats for current application.  These are not cleared until a new app connects,
+* but they do stop accumulating once the associated app disconnects. */
+struct Compositor_CumulativeStats
+{
+        uint32_t m_nPid; // Process id associated with these stats (may no longer be running).
+        uint32_t m_nNumFramePresents; // total number of times we called present (includes reprojected frames)
+        uint32_t m_nNumDroppedFrames; // total number of times an old frame was re-scanned out (without reprojection)
+        uint32_t m_nNumReprojectedFrames; // total number of times a frame was scanned out a second time (with reprojection)
+
+        /** Values recorded at startup before application has fully faded in the first time. */
+        uint32_t m_nNumFramePresentsOnStartup;
+        uint32_t m_nNumDroppedFramesOnStartup;
+        uint32_t m_nNumReprojectedFramesOnStartup;
+
+        /** Applications may explicitly fade to the compositor.  This is usually to handle level transitions, and loading often causes
+        * system wide hitches.  The following stats are collected during this period.  Does not include values recorded during startup. */
+        uint32_t m_nNumLoading;
+        uint32_t m_nNumFramePresentsLoading;
+        uint32_t m_nNumDroppedFramesLoading;
+        uint32_t m_nNumReprojectedFramesLoading;
+
+        /** If we don't get a new frame from the app in less than 2.5 frames, then we assume the app has hung and start
+        * fading back to the compositor.  The following stats are a result of this, and are a subset of those recorded above.
+        * Does not include values recorded during start up or loading. */
+        uint32_t m_nNumTimedOut;
+        uint32_t m_nNumFramePresentsTimedOut;
+        uint32_t m_nNumDroppedFramesTimedOut;
+        uint32_t m_nNumReprojectedFramesTimedOut;
+};
+
+#pragma pack( pop )
+
+/** Allows the application to interact with the compositor */
+class IVRCompositor
+{
+public:
+        /** Sets tracking space returned by WaitGetPoses */
+        virtual void SetTrackingSpace( ETrackingUniverseOrigin eOrigin ) = 0;
+
+        /** Gets current tracking space returned by WaitGetPoses */
+        virtual ETrackingUniverseOrigin GetTrackingSpace() = 0;
+
+        /** Scene applications should call this function to get poses to render with (and optionally poses predicted an additional frame out to use for gameplay).
+        * This function will block until "running start" milliseconds before the start of the frame, and should be called at the last moment before needing to
+        * start rendering.
+        *
+        * Return codes:
+        *       - IsNotSceneApplication (make sure to call VR_Init with VRApplicaiton_Scene)
+        *       - DoNotHaveFocus (some other app has taken focus - this will throttle the call to 10hz to reduce the impact on that app)
+        */
+        virtual EVRCompositorError WaitGetPoses( VR_ARRAY_COUNT(unRenderPoseArrayCount) TrackedDevicePose_t* pRenderPoseArray, uint32_t unRenderPoseArrayCount,
+                VR_ARRAY_COUNT(unGamePoseArrayCount) TrackedDevicePose_t* pGamePoseArray, uint32_t unGamePoseArrayCount ) = 0;
+
+        /** Get the last set of poses returned by WaitGetPoses. */
+        virtual EVRCompositorError GetLastPoses( VR_ARRAY_COUNT( unRenderPoseArrayCount ) TrackedDevicePose_t* pRenderPoseArray, uint32_t unRenderPoseArrayCount,
+                VR_ARRAY_COUNT( unGamePoseArrayCount ) TrackedDevicePose_t* pGamePoseArray, uint32_t unGamePoseArrayCount ) = 0;
+
+        /** Interface for accessing last set of poses returned by WaitGetPoses one at a time.
+        * Returns VRCompositorError_IndexOutOfRange if unDeviceIndex not less than k_unMaxTrackedDeviceCount otherwise VRCompositorError_None.
+        * It is okay to pass NULL for either pose if you only want one of the values. */
+        virtual EVRCompositorError GetLastPoseForTrackedDeviceIndex( TrackedDeviceIndex_t unDeviceIndex, TrackedDevicePose_t *pOutputPose, TrackedDevicePose_t *pOutputGamePose ) = 0;
+
+        /** Updated scene texture to display. If pBounds is NULL the entire texture will be used.  If called from an OpenGL app, consider adding a glFlush after
+        * Submitting both frames to signal the driver to start processing, otherwise it may wait until the command buffer fills up, causing the app to miss frames.
+        *
+        * OpenGL dirty state:
+        *       glBindTexture
+        *
+        * Return codes:
+        *       - IsNotSceneApplication (make sure to call VR_Init with VRApplicaiton_Scene)
+        *       - DoNotHaveFocus (some other app has taken focus)
+        *       - TextureIsOnWrongDevice (application did not use proper AdapterIndex - see IVRSystem.GetDXGIOutputInfo)
+        *       - SharedTexturesNotSupported (application needs to call CreateDXGIFactory1 or later before creating DX device)
+        *       - TextureUsesUnsupportedFormat (scene textures must be compatible with DXGI sharing rules - e.g. uncompressed, no mips, etc.)
+        *       - InvalidTexture (usually means bad arguments passed in)
+        *       - AlreadySubmitted (app has submitted two left textures or two right textures in a single frame - i.e. before calling WaitGetPoses again)
+        */
+        virtual EVRCompositorError Submit( EVREye eEye, const Texture_t *pTexture, const VRTextureBounds_t* pBounds = 0, EVRSubmitFlags nSubmitFlags = Submit_Default ) = 0;
+
+        /** Clears the frame that was sent with the last call to Submit. This will cause the 
+        * compositor to show the grid until Submit is called again. */
+        virtual void ClearLastSubmittedFrame() = 0;
+
+        /** Call immediately after presenting your app's window (i.e. companion window) to unblock the compositor.
+        * This is an optional call, which only needs to be used if you can't instead call WaitGetPoses immediately after Present.
+        * For example, if your engine's render and game loop are not on separate threads, or blocking the render thread until 3ms before the next vsync would
+        * introduce a deadlock of some sort.  This function tells the compositor that you have finished all rendering after having Submitted buffers for both
+        * eyes, and it is free to start its rendering work.  This should only be called from the same thread you are rendering on. */
+        virtual void PostPresentHandoff() = 0;
+
+        /** Returns true if timing data is filled it.  Sets oldest timing info if nFramesAgo is larger than the stored history.
+        * Be sure to set timing.size = sizeof(Compositor_FrameTiming) on struct passed in before calling this function. */
+        virtual bool GetFrameTiming( Compositor_FrameTiming *pTiming, uint32_t unFramesAgo = 0 ) = 0;
+
+        /** Interface for copying a range of timing data.  Frames are returned in ascending order (oldest to newest) with the last being the most recent frame.
+        * Only the first entry's m_nSize needs to be set, as the rest will be inferred from that.  Returns total number of entries filled out. */
+        virtual uint32_t GetFrameTimings( Compositor_FrameTiming *pTiming, uint32_t nFrames ) = 0;
+
+        /** Returns the time in seconds left in the current (as identified by FrameTiming's frameIndex) frame.
+        * Due to "running start", this value may roll over to the next frame before ever reaching 0.0. */
+        virtual float GetFrameTimeRemaining() = 0;
+
+        /** Fills out stats accumulated for the last connected application.  Pass in sizeof( Compositor_CumulativeStats ) as second parameter. */
+        virtual void GetCumulativeStats( Compositor_CumulativeStats *pStats, uint32_t nStatsSizeInBytes ) = 0;
+
+        /** Fades the view on the HMD to the specified color. The fade will take fSeconds, and the color values are between
+        * 0.0 and 1.0. This color is faded on top of the scene based on the alpha parameter. Removing the fade color instantly 
+        * would be FadeToColor( 0.0, 0.0, 0.0, 0.0, 0.0 ).  Values are in un-premultiplied alpha space. */
+        virtual void FadeToColor( float fSeconds, float fRed, float fGreen, float fBlue, float fAlpha, bool bBackground = false ) = 0;
+
+        /** Get current fade color value. */
+        virtual HmdColor_t GetCurrentFadeColor( bool bBackground = false ) = 0;
+
+        /** Fading the Grid in or out in fSeconds */
+        virtual void FadeGrid( float fSeconds, bool bFadeIn ) = 0;
+
+        /** Get current alpha value of grid. */
+        virtual float GetCurrentGridAlpha() = 0;
+
+        /** Override the skybox used in the compositor (e.g. for during level loads when the app can't feed scene images fast enough)
+        * Order is Front, Back, Left, Right, Top, Bottom.  If only a single texture is passed, it is assumed in lat-long format.
+        * If two are passed, it is assumed a lat-long stereo pair. */
+        virtual EVRCompositorError SetSkyboxOverride( VR_ARRAY_COUNT( unTextureCount ) const Texture_t *pTextures, uint32_t unTextureCount ) = 0;
+
+        /** Resets compositor skybox back to defaults. */
+        virtual void ClearSkyboxOverride() = 0;
+
+        /** Brings the compositor window to the front. This is useful for covering any other window that may be on the HMD
+        * and is obscuring the compositor window. */
+        virtual void CompositorBringToFront() = 0;
+
+        /** Pushes the compositor window to the back. This is useful for allowing other applications to draw directly to the HMD. */
+        virtual void CompositorGoToBack() = 0;
+
+        /** Tells the compositor process to clean up and exit. You do not need to call this function at shutdown. Under normal 
+        * circumstances the compositor will manage its own life cycle based on what applications are running. */
+        virtual void CompositorQuit() = 0;
+        
+        /** Return whether the compositor is fullscreen */
+        virtual bool IsFullscreen() = 0;
+
+        /** Returns the process ID of the process that is currently rendering the scene */
+        virtual uint32_t GetCurrentSceneFocusProcess() = 0;
+
+        /** Returns the process ID of the process that rendered the last frame (or 0 if the compositor itself rendered the frame.)
+        * Returns 0 when fading out from an app and the app's process Id when fading into an app. */
+        virtual uint32_t GetLastFrameRenderer() = 0;
+
+        /** Returns true if the current process has the scene focus */
+        virtual bool CanRenderScene() = 0;
+
+        /** Creates a window on the primary monitor to display what is being shown in the headset. */
+        virtual void ShowMirrorWindow() = 0;
+
+        /** Closes the mirror window. */
+        virtual void HideMirrorWindow() = 0;
+
+        /** Returns true if the mirror window is shown. */
+        virtual bool IsMirrorWindowVisible() = 0;
+
+        /** Writes all images that the compositor knows about (including overlays) to a 'screenshots' folder in the SteamVR runtime root. */
+        virtual void CompositorDumpImages() = 0;
+
+        /** Let an app know it should be rendering with low resources. */
+        virtual bool ShouldAppRenderWithLowResources() = 0;
+
+        /** Override interleaved reprojection logic to force on. */
+        virtual void ForceInterleavedReprojectionOn( bool bOverride ) = 0;
+
+        /** Force reconnecting to the compositor process. */
+        virtual void ForceReconnectProcess() = 0;
+
+        /** Temporarily suspends rendering (useful for finer control over scene transitions). */
+        virtual void SuspendRendering( bool bSuspend ) = 0;
+
+        /** Opens a shared D3D11 texture with the undistorted composited image for each eye.  Use ReleaseMirrorTextureD3D11 when finished
+        * instead of calling Release on the resource itself. */
+        virtual vr::EVRCompositorError GetMirrorTextureD3D11( vr::EVREye eEye, void *pD3D11DeviceOrResource, void **ppD3D11ShaderResourceView ) = 0;
+        virtual void ReleaseMirrorTextureD3D11( void *pD3D11ShaderResourceView ) = 0;
+
+        /** Access to mirror textures from OpenGL. */
+        virtual vr::EVRCompositorError GetMirrorTextureGL( vr::EVREye eEye, vr::glUInt_t *pglTextureId, vr::glSharedTextureHandle_t *pglSharedTextureHandle ) = 0;
+        virtual bool ReleaseSharedGLTexture( vr::glUInt_t glTextureId, vr::glSharedTextureHandle_t glSharedTextureHandle ) = 0;
+        virtual void LockGLSharedTextureForAccess( vr::glSharedTextureHandle_t glSharedTextureHandle ) = 0;
+        virtual void UnlockGLSharedTextureForAccess( vr::glSharedTextureHandle_t glSharedTextureHandle ) = 0;
+
+        /** [Vulkan Only]
+        * return 0. Otherwise it returns the length of the number of bytes necessary to hold this string including the trailing
+        * null.  The string will be a space separated list of-required instance extensions to enable in VkCreateInstance */
+        virtual uint32_t GetVulkanInstanceExtensionsRequired( VR_OUT_STRING() char *pchValue, uint32_t unBufferSize ) = 0;
+
+        /** [Vulkan only]
+        * return 0. Otherwise it returns the length of the number of bytes necessary to hold this string including the trailing
+        * null.  The string will be a space separated list of required device extensions to enable in VkCreateDevice */
+        virtual uint32_t GetVulkanDeviceExtensionsRequired( VkPhysicalDevice_T *pPhysicalDevice, VR_OUT_STRING() char *pchValue, uint32_t unBufferSize ) = 0;
+
+};
+
+static const char * const IVRCompositor_Version = "IVRCompositor_020";
+
+} // namespace vr
+
+
+
+// ivrnotifications.h
+namespace vr
+{
+
+#if defined(__linux__) || defined(__APPLE__) 
+        // The 32-bit version of gcc has the alignment requirement for uint64 and double set to
+        // 4 meaning that even with #pragma pack(8) these types will only be four-byte aligned.
+        // The 64-bit version of gcc has the alignment requirement for these types set to
+        // 8 meaning that unless we use #pragma pack(4) our structures will get bigger.
+        // The 64-bit structure packing has to match the 32-bit structure packing for each platform.
+        #pragma pack( push, 4 )
+#else
+        #pragma pack( push, 8 )
+#endif
+
+// Used for passing graphic data
+struct NotificationBitmap_t
+{
+        NotificationBitmap_t()
+                : m_pImageData( nullptr )
+                , m_nWidth( 0 )
+                , m_nHeight( 0 )
+                , m_nBytesPerPixel( 0 )
+        {
+        };
+
+        void *m_pImageData;
+        int32_t m_nWidth;
+        int32_t m_nHeight;
+        int32_t m_nBytesPerPixel;
+};
+
+
+/** Be aware that the notification type is used as 'priority' to pick the next notification */
+enum EVRNotificationType
+{
+        /** Transient notifications are automatically hidden after a period of time set by the user. 
+        * They are used for things like information and chat messages that do not require user interaction. */
+        EVRNotificationType_Transient = 0,
+
+        /** Persistent notifications are shown to the user until they are hidden by calling RemoveNotification().
+        * They are used for things like phone calls and alarms that require user interaction. */
+        EVRNotificationType_Persistent = 1,
+
+        /** System notifications are shown no matter what. It is expected, that the ulUserValue is used as ID.
+         * If there is already a system notification in the queue with that ID it is not accepted into the queue
+         * to prevent spamming with system notification */
+        EVRNotificationType_Transient_SystemWithUserValue = 2,
+};
+
+enum EVRNotificationStyle
+{
+        /** Creates a notification with minimal external styling. */
+        EVRNotificationStyle_None = 0,
+
+        /** Used for notifications about overlay-level status. In Steam this is used for events like downloads completing. */
+        EVRNotificationStyle_Application = 100,
+
+        /** Used for notifications about contacts that are unknown or not available. In Steam this is used for friend invitations and offline friends. */
+        EVRNotificationStyle_Contact_Disabled = 200,
+
+        /** Used for notifications about contacts that are available but inactive. In Steam this is used for friends that are online but not playing a game. */
+        EVRNotificationStyle_Contact_Enabled = 201,
+
+        /** Used for notifications about contacts that are available and active. In Steam this is used for friends that are online and currently running a game. */
+        EVRNotificationStyle_Contact_Active = 202,
+};
+
+static const uint32_t k_unNotificationTextMaxSize = 256;
+
+typedef uint32_t VRNotificationId;
+
+
+
+#pragma pack( pop )
+
+/** Allows notification sources to interact with the VR system
+        This current interface is not yet implemented. Do not use yet. */
+class IVRNotifications
+{
+public:
+        /** Create a notification and enqueue it to be shown to the user.
+        * An overlay handle is required to create a notification, as otherwise it would be impossible for a user to act on it.
+        * To create a two-line notification, use a line break ('\n') to split the text into two lines.
+        * The pImage argument may be NULL, in which case the specified overlay's icon will be used instead. */
+        virtual EVRNotificationError CreateNotification( VROverlayHandle_t ulOverlayHandle, uint64_t ulUserValue, EVRNotificationType type, const char *pchText, EVRNotificationStyle style, const NotificationBitmap_t *pImage, /* out */ VRNotificationId *pNotificationId ) = 0;
+
+        /** Destroy a notification, hiding it first if it currently shown to the user. */
+        virtual EVRNotificationError RemoveNotification( VRNotificationId notificationId ) = 0;
+
+};
+
+static const char * const IVRNotifications_Version = "IVRNotifications_002";
+
+} // namespace vr
+
+
+
+// ivroverlay.h
+namespace vr
+{
+
+        /** The maximum length of an overlay key in bytes, counting the terminating null character. */
+        static const uint32_t k_unVROverlayMaxKeyLength = 128;
+
+        /** The maximum length of an overlay name in bytes, counting the terminating null character. */
+        static const uint32_t k_unVROverlayMaxNameLength = 128;
+
+        /** The maximum number of overlays that can exist in the system at one time. */
+        static const uint32_t k_unMaxOverlayCount = 64;
+
+        /** The maximum number of overlay intersection mask primitives per overlay */
+        static const uint32_t k_unMaxOverlayIntersectionMaskPrimitivesCount = 32;
+
+        /** Types of input supported by VR Overlays */
+        enum VROverlayInputMethod
+        {
+                VROverlayInputMethod_None               = 0, // No input events will be generated automatically for this overlay
+                VROverlayInputMethod_Mouse              = 1, // Tracked controllers will get mouse events automatically
+        };
+
+        /** Allows the caller to figure out which overlay transform getter to call. */
+        enum VROverlayTransformType
+        {
+                VROverlayTransform_Absolute                                     = 0,
+                VROverlayTransform_TrackedDeviceRelative        = 1,
+                VROverlayTransform_SystemOverlay                        = 2,
+                VROverlayTransform_TrackedComponent             = 3,
+        };
+
+        /** Overlay control settings */
+        enum VROverlayFlags
+        {
+                VROverlayFlags_None                     = 0,
+
+                // The following only take effect when rendered using the high quality render path (see SetHighQualityOverlay).
+                VROverlayFlags_Curved           = 1,
+                VROverlayFlags_RGSS4X           = 2,
+
+                // Set this flag on a dashboard overlay to prevent a tab from showing up for that overlay
+                VROverlayFlags_NoDashboardTab = 3,
+
+                // Set this flag on a dashboard that is able to deal with gamepad focus events
+                VROverlayFlags_AcceptsGamepadEvents = 4,
+
+                // Indicates that the overlay should dim/brighten to show gamepad focus
+                VROverlayFlags_ShowGamepadFocus = 5,
+
+                // When in VROverlayInputMethod_Mouse you can optionally enable sending VRScroll_t 
+                VROverlayFlags_SendVRScrollEvents = 6,
+                VROverlayFlags_SendVRTouchpadEvents = 7,
+
+                // If set this will render a vertical scroll wheel on the primary controller, 
+                //  only needed if not using VROverlayFlags_SendVRScrollEvents but you still want to represent a scroll wheel
+                VROverlayFlags_ShowTouchPadScrollWheel = 8,
+
+                // If this is set ownership and render access to the overlay are transferred 
+                // to the new scene process on a call to IVRApplications::LaunchInternalProcess
+                VROverlayFlags_TransferOwnershipToInternalProcess = 9,
+
+                // If set, renders 50% of the texture in each eye, side by side
+                VROverlayFlags_SideBySide_Parallel = 10, // Texture is left/right
+                VROverlayFlags_SideBySide_Crossed = 11, // Texture is crossed and right/left
+
+                VROverlayFlags_Panorama = 12, // Texture is a panorama
+                VROverlayFlags_StereoPanorama = 13, // Texture is a stereo panorama
+
+                // If this is set on an overlay owned by the scene application that overlay
+                // will be sorted with the "Other" overlays on top of all other scene overlays
+                VROverlayFlags_SortWithNonSceneOverlays = 14,
+
+                // If set, the overlay will be shown in the dashboard, otherwise it will be hidden.
+                VROverlayFlags_VisibleInDashboard = 15,
+        };
+
+        enum VRMessageOverlayResponse
+        {
+                VRMessageOverlayResponse_ButtonPress_0 = 0,
+                VRMessageOverlayResponse_ButtonPress_1 = 1,
+                VRMessageOverlayResponse_ButtonPress_2 = 2,
+                VRMessageOverlayResponse_ButtonPress_3 = 3,
+                VRMessageOverlayResponse_CouldntFindSystemOverlay = 4,
+                VRMessageOverlayResponse_CouldntFindOrCreateClientOverlay= 5,
+                VRMessageOverlayResponse_ApplicationQuit = 6
+        };
+
+        struct VROverlayIntersectionParams_t
+        {
+                HmdVector3_t vSource;
+                HmdVector3_t vDirection;
+                ETrackingUniverseOrigin eOrigin;
+        };
+
+        struct VROverlayIntersectionResults_t
+        {
+                HmdVector3_t vPoint;
+                HmdVector3_t vNormal;
+                HmdVector2_t vUVs;
+                float fDistance;
+        };
+
+        // Input modes for the Big Picture gamepad text entry
+        enum EGamepadTextInputMode
+        {
+                k_EGamepadTextInputModeNormal = 0,
+                k_EGamepadTextInputModePassword = 1,
+                k_EGamepadTextInputModeSubmit = 2,
+        };
+
+        // Controls number of allowed lines for the Big Picture gamepad text entry
+        enum EGamepadTextInputLineMode
+        {
+                k_EGamepadTextInputLineModeSingleLine = 0,
+                k_EGamepadTextInputLineModeMultipleLines = 1
+        };
+
+        /** Directions for changing focus between overlays with the gamepad */
+        enum EOverlayDirection
+        {
+                OverlayDirection_Up = 0,
+                OverlayDirection_Down = 1,
+                OverlayDirection_Left = 2,
+                OverlayDirection_Right = 3,
+                
+                OverlayDirection_Count = 4,
+        };
+
+        enum EVROverlayIntersectionMaskPrimitiveType
+        {
+                OverlayIntersectionPrimitiveType_Rectangle,
+                OverlayIntersectionPrimitiveType_Circle,
+        };
+
+        struct IntersectionMaskRectangle_t
+        {
+                float m_flTopLeftX;
+                float m_flTopLeftY;
+                float m_flWidth;
+                float m_flHeight;
+        };
+
+        struct IntersectionMaskCircle_t
+        {
+                float m_flCenterX;
+                float m_flCenterY;
+                float m_flRadius;
+        };
+
+        /** NOTE!!! If you change this you MUST manually update openvr_interop.cs.py and openvr_api_flat.h.py */
+        typedef union
+        {
+                IntersectionMaskRectangle_t m_Rectangle;
+                IntersectionMaskCircle_t m_Circle;
+        } VROverlayIntersectionMaskPrimitive_Data_t;
+
+        struct VROverlayIntersectionMaskPrimitive_t
+        {
+                EVROverlayIntersectionMaskPrimitiveType m_nPrimitiveType;
+                VROverlayIntersectionMaskPrimitive_Data_t m_Primitive;
+        };
+
+        class IVROverlay
+        {
+        public:
+
+                // ---------------------------------------------
+                // Overlay management methods
+                // ---------------------------------------------
+
+                /** Finds an existing overlay with the specified key. */
+                virtual EVROverlayError FindOverlay( const char *pchOverlayKey, VROverlayHandle_t * pOverlayHandle ) = 0;
+
+                /** Creates a new named overlay. All overlays start hidden and with default settings. */
+                virtual EVROverlayError CreateOverlay( const char *pchOverlayKey, const char *pchOverlayFriendlyName, VROverlayHandle_t * pOverlayHandle ) = 0;
+
+                /** Destroys the specified overlay. When an application calls VR_Shutdown all overlays created by that app are
+                * automatically destroyed. */
+                virtual EVROverlayError DestroyOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Specify which overlay to use the high quality render path.  This overlay will be composited in during the distortion pass which
+                * results in it drawing on top of everything else, but also at a higher quality as it samples the source texture directly rather than
+                * rasterizing into each eye's render texture first.  Because if this, only one of these is supported at any given time.  It is most useful
+                * for overlays that are expected to take up most of the user's view (e.g. streaming video).
+                * This mode does not support mouse input to your overlay. */
+                virtual EVROverlayError SetHighQualityOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Returns the overlay handle of the current overlay being rendered using the single high quality overlay render path.
+                * Otherwise it will return k_ulOverlayHandleInvalid. */
+                virtual vr::VROverlayHandle_t GetHighQualityOverlay() = 0;
+
+                /** Fills the provided buffer with the string key of the overlay. Returns the size of buffer required to store the key, including
+                * the terminating null character. k_unVROverlayMaxKeyLength will be enough bytes to fit the string. */
+                virtual uint32_t GetOverlayKey( VROverlayHandle_t ulOverlayHandle, VR_OUT_STRING() char *pchValue, uint32_t unBufferSize, EVROverlayError *pError = 0L ) = 0;
+
+                /** Fills the provided buffer with the friendly name of the overlay. Returns the size of buffer required to store the key, including
+                * the terminating null character. k_unVROverlayMaxNameLength will be enough bytes to fit the string. */
+                virtual uint32_t GetOverlayName( VROverlayHandle_t ulOverlayHandle, VR_OUT_STRING() char *pchValue, uint32_t unBufferSize, EVROverlayError *pError = 0L ) = 0;
+
+                /** Gets the raw image data from an overlay. Overlay image data is always returned as RGBA data, 4 bytes per pixel. If the buffer is not large enough, width and height 
+                * will be set and VROverlayError_ArrayTooSmall is returned. */
+                virtual EVROverlayError GetOverlayImageData( VROverlayHandle_t ulOverlayHandle, void *pvBuffer, uint32_t unBufferSize, uint32_t *punWidth, uint32_t *punHeight ) = 0;
+
+                /** returns a string that corresponds with the specified overlay error. The string will be the name 
+                * of the error enum value for all valid error codes */
+                virtual const char *GetOverlayErrorNameFromEnum( EVROverlayError error ) = 0;
+
+
+                // ---------------------------------------------
+                // Overlay rendering methods
+                // ---------------------------------------------
+
+                /** Sets the pid that is allowed to render to this overlay (the creator pid is always allow to render),
+                *       by default this is the pid of the process that made the overlay */
+                virtual EVROverlayError SetOverlayRenderingPid( VROverlayHandle_t ulOverlayHandle, uint32_t unPID ) = 0;
+
+                /** Gets the pid that is allowed to render to this overlay */
+                virtual uint32_t GetOverlayRenderingPid( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Specify flag setting for a given overlay */
+                virtual EVROverlayError SetOverlayFlag( VROverlayHandle_t ulOverlayHandle, VROverlayFlags eOverlayFlag, bool bEnabled ) = 0;
+
+                /** Sets flag setting for a given overlay */
+                virtual EVROverlayError GetOverlayFlag( VROverlayHandle_t ulOverlayHandle, VROverlayFlags eOverlayFlag, bool *pbEnabled ) = 0;
+
+                /** Sets the color tint of the overlay quad. Use 0.0 to 1.0 per channel. */
+                virtual EVROverlayError SetOverlayColor( VROverlayHandle_t ulOverlayHandle, float fRed, float fGreen, float fBlue ) = 0;
+
+                /** Gets the color tint of the overlay quad. */
+                virtual EVROverlayError GetOverlayColor( VROverlayHandle_t ulOverlayHandle, float *pfRed, float *pfGreen, float *pfBlue ) = 0;
+
+                /** Sets the alpha of the overlay quad. Use 1.0 for 100 percent opacity to 0.0 for 0 percent opacity. */
+                virtual EVROverlayError SetOverlayAlpha( VROverlayHandle_t ulOverlayHandle, float fAlpha ) = 0;
+
+                /** Gets the alpha of the overlay quad. By default overlays are rendering at 100 percent alpha (1.0). */
+                virtual EVROverlayError GetOverlayAlpha( VROverlayHandle_t ulOverlayHandle, float *pfAlpha ) = 0;
+
+                /** Sets the aspect ratio of the texels in the overlay. 1.0 means the texels are square. 2.0 means the texels
+                * are twice as wide as they are tall. Defaults to 1.0. */
+                virtual EVROverlayError SetOverlayTexelAspect( VROverlayHandle_t ulOverlayHandle, float fTexelAspect ) = 0;
+
+                /** Gets the aspect ratio of the texels in the overlay. Defaults to 1.0 */
+                virtual EVROverlayError GetOverlayTexelAspect( VROverlayHandle_t ulOverlayHandle, float *pfTexelAspect ) = 0;
+
+                /** Sets the rendering sort order for the overlay. Overlays are rendered this order:
+                *      Overlays owned by the scene application
+                *      Overlays owned by some other application
+                *
+                *       Within a category overlays are rendered lowest sort order to highest sort order. Overlays with the same 
+                *       sort order are rendered back to front base on distance from the HMD.
+                *
+                *       Sort order defaults to 0. */
+                virtual EVROverlayError SetOverlaySortOrder( VROverlayHandle_t ulOverlayHandle, uint32_t unSortOrder ) = 0;
+
+                /** Gets the sort order of the overlay. See SetOverlaySortOrder for how this works. */
+                virtual EVROverlayError GetOverlaySortOrder( VROverlayHandle_t ulOverlayHandle, uint32_t *punSortOrder ) = 0;
+
+                /** Sets the width of the overlay quad in meters. By default overlays are rendered on a quad that is 1 meter across */
+                virtual EVROverlayError SetOverlayWidthInMeters( VROverlayHandle_t ulOverlayHandle, float fWidthInMeters ) = 0;
+
+                /** Returns the width of the overlay quad in meters. By default overlays are rendered on a quad that is 1 meter across */
+                virtual EVROverlayError GetOverlayWidthInMeters( VROverlayHandle_t ulOverlayHandle, float *pfWidthInMeters ) = 0;
+
+                /** For high-quality curved overlays only, sets the distance range in meters from the overlay used to automatically curve
+                * the surface around the viewer.  Min is distance is when the surface will be most curved.  Max is when least curved. */
+                virtual EVROverlayError SetOverlayAutoCurveDistanceRangeInMeters( VROverlayHandle_t ulOverlayHandle, float fMinDistanceInMeters, float fMaxDistanceInMeters ) = 0;
+
+                /** For high-quality curved overlays only, gets the distance range in meters from the overlay used to automatically curve
+                * the surface around the viewer.  Min is distance is when the surface will be most curved.  Max is when least curved. */
+                virtual EVROverlayError GetOverlayAutoCurveDistanceRangeInMeters( VROverlayHandle_t ulOverlayHandle, float *pfMinDistanceInMeters, float *pfMaxDistanceInMeters ) = 0;
+
+                /** Sets the colorspace the overlay texture's data is in.  Defaults to 'auto'.
+                * If the texture needs to be resolved, you should call SetOverlayTexture with the appropriate colorspace instead. */
+                virtual EVROverlayError SetOverlayTextureColorSpace( VROverlayHandle_t ulOverlayHandle, EColorSpace eTextureColorSpace ) = 0;
+
+                /** Gets the overlay's current colorspace setting. */
+                virtual EVROverlayError GetOverlayTextureColorSpace( VROverlayHandle_t ulOverlayHandle, EColorSpace *peTextureColorSpace ) = 0;
+
+                /** Sets the part of the texture to use for the overlay. UV Min is the upper left corner and UV Max is the lower right corner. */
+                virtual EVROverlayError SetOverlayTextureBounds( VROverlayHandle_t ulOverlayHandle, const VRTextureBounds_t *pOverlayTextureBounds ) = 0;
+
+                /** Gets the part of the texture to use for the overlay. UV Min is the upper left corner and UV Max is the lower right corner. */
+                virtual EVROverlayError GetOverlayTextureBounds( VROverlayHandle_t ulOverlayHandle, VRTextureBounds_t *pOverlayTextureBounds ) = 0;
+
+                /** Returns the transform type of this overlay. */
+                virtual EVROverlayError GetOverlayTransformType( VROverlayHandle_t ulOverlayHandle, VROverlayTransformType *peTransformType ) = 0;
+
+                /** Sets the transform to absolute tracking origin. */
+                virtual EVROverlayError SetOverlayTransformAbsolute( VROverlayHandle_t ulOverlayHandle, ETrackingUniverseOrigin eTrackingOrigin, const HmdMatrix34_t *pmatTrackingOriginToOverlayTransform ) = 0;
+
+                /** Gets the transform if it is absolute. Returns an error if the transform is some other type. */
+                virtual EVROverlayError GetOverlayTransformAbsolute( VROverlayHandle_t ulOverlayHandle, ETrackingUniverseOrigin *peTrackingOrigin, HmdMatrix34_t *pmatTrackingOriginToOverlayTransform ) = 0;
+
+                /** Sets the transform to relative to the transform of the specified tracked device. */
+                virtual EVROverlayError SetOverlayTransformTrackedDeviceRelative( VROverlayHandle_t ulOverlayHandle, TrackedDeviceIndex_t unTrackedDevice, const HmdMatrix34_t *pmatTrackedDeviceToOverlayTransform ) = 0;
+
+                /** Gets the transform if it is relative to a tracked device. Returns an error if the transform is some other type. */
+                virtual EVROverlayError GetOverlayTransformTrackedDeviceRelative( VROverlayHandle_t ulOverlayHandle, TrackedDeviceIndex_t *punTrackedDevice, HmdMatrix34_t *pmatTrackedDeviceToOverlayTransform ) = 0;
+
+                /** Sets the transform to draw the overlay on a rendermodel component mesh instead of a quad. This will only draw when the system is
+                * drawing the device. Overlays with this transform type cannot receive mouse events. */
+                virtual EVROverlayError SetOverlayTransformTrackedDeviceComponent( VROverlayHandle_t ulOverlayHandle, TrackedDeviceIndex_t unDeviceIndex, const char *pchComponentName ) = 0;
+
+                /** Gets the transform information when the overlay is rendering on a component. */
+                virtual EVROverlayError GetOverlayTransformTrackedDeviceComponent( VROverlayHandle_t ulOverlayHandle, TrackedDeviceIndex_t *punDeviceIndex, char *pchComponentName, uint32_t unComponentNameSize ) = 0;
+
+                /** Shows the VR overlay.  For dashboard overlays, only the Dashboard Manager is allowed to call this. */
+                virtual EVROverlayError ShowOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Hides the VR overlay.  For dashboard overlays, only the Dashboard Manager is allowed to call this. */
+                virtual EVROverlayError HideOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Returns true if the overlay is visible. */
+                virtual bool IsOverlayVisible( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Get the transform in 3d space associated with a specific 2d point in the overlay's coordinate space (where 0,0 is the lower left). -Z points out of the overlay */
+                virtual EVROverlayError GetTransformForOverlayCoordinates( VROverlayHandle_t ulOverlayHandle, ETrackingUniverseOrigin eTrackingOrigin, HmdVector2_t coordinatesInOverlay, HmdMatrix34_t *pmatTransform ) = 0;
+
+                // ---------------------------------------------
+                // Overlay input methods
+                // ---------------------------------------------
+
+                /** Returns true and fills the event with the next event on the overlay's event queue, if there is one. 
+                * If there are no events this method returns false. uncbVREvent should be the size in bytes of the VREvent_t struct */
+                virtual bool PollNextOverlayEvent( VROverlayHandle_t ulOverlayHandle, VREvent_t *pEvent, uint32_t uncbVREvent ) = 0;
+
+                /** Returns the current input settings for the specified overlay. */
+                virtual EVROverlayError GetOverlayInputMethod( VROverlayHandle_t ulOverlayHandle, VROverlayInputMethod *peInputMethod ) = 0;
+
+                /** Sets the input settings for the specified overlay. */
+                virtual EVROverlayError SetOverlayInputMethod( VROverlayHandle_t ulOverlayHandle, VROverlayInputMethod eInputMethod ) = 0;
+
+                /** Gets the mouse scaling factor that is used for mouse events. The actual texture may be a different size, but this is
+                * typically the size of the underlying UI in pixels. */
+                virtual EVROverlayError GetOverlayMouseScale( VROverlayHandle_t ulOverlayHandle, HmdVector2_t *pvecMouseScale ) = 0;
+
+                /** Sets the mouse scaling factor that is used for mouse events. The actual texture may be a different size, but this is
+                * typically the size of the underlying UI in pixels (not in world space). */
+                virtual EVROverlayError SetOverlayMouseScale( VROverlayHandle_t ulOverlayHandle, const HmdVector2_t *pvecMouseScale ) = 0;
+
+                /** Computes the overlay-space pixel coordinates of where the ray intersects the overlay with the
+                * specified settings. Returns false if there is no intersection. */
+                virtual bool ComputeOverlayIntersection( VROverlayHandle_t ulOverlayHandle, const VROverlayIntersectionParams_t *pParams, VROverlayIntersectionResults_t *pResults ) = 0;
+
+                /** Processes mouse input from the specified controller as though it were a mouse pointed at a compositor overlay with the
+                * specified settings. The controller is treated like a laser pointer on the -z axis. The point where the laser pointer would
+                * intersect with the overlay is the mouse position, the trigger is left mouse, and the track pad is right mouse. 
+                *
+                * Return true if the controller is pointed at the overlay and an event was generated. */
+                virtual bool HandleControllerOverlayInteractionAsMouse( VROverlayHandle_t ulOverlayHandle, TrackedDeviceIndex_t unControllerDeviceIndex ) = 0;
+
+                /** Returns true if the specified overlay is the hover target. An overlay is the hover target when it is the last overlay "moused over" 
+                * by the virtual mouse pointer */
+                virtual bool IsHoverTargetOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Returns the current Gamepad focus overlay */
+                virtual vr::VROverlayHandle_t GetGamepadFocusOverlay() = 0;
+
+                /** Sets the current Gamepad focus overlay */
+                virtual EVROverlayError SetGamepadFocusOverlay( VROverlayHandle_t ulNewFocusOverlay ) = 0;
+
+                /** Sets an overlay's neighbor. This will also set the neighbor of the "to" overlay
+                * to point back to the "from" overlay. If an overlay's neighbor is set to invalid both
+                * ends will be cleared */
+                virtual EVROverlayError SetOverlayNeighbor( EOverlayDirection eDirection, VROverlayHandle_t ulFrom, VROverlayHandle_t ulTo ) = 0;
+
+                /** Changes the Gamepad focus from one overlay to one of its neighbors. Returns VROverlayError_NoNeighbor if there is no
+                * neighbor in that direction */
+                virtual EVROverlayError MoveGamepadFocusToNeighbor( EOverlayDirection eDirection, VROverlayHandle_t ulFrom ) = 0;
+
+                // ---------------------------------------------
+                // Overlay texture methods
+                // ---------------------------------------------
+
+                /** Texture to draw for the overlay. This function can only be called by the overlay's creator or renderer process (see SetOverlayRenderingPid) .
+                *
+                * OpenGL dirty state:
+                *       glBindTexture
+                */
+                virtual EVROverlayError SetOverlayTexture( VROverlayHandle_t ulOverlayHandle, const Texture_t *pTexture ) = 0;
+
+                /** Use this to tell the overlay system to release the texture set for this overlay. */
+                virtual EVROverlayError ClearOverlayTexture( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Separate interface for providing the data as a stream of bytes, but there is an upper bound on data 
+                * that can be sent. This function can only be called by the overlay's renderer process. */
+                virtual EVROverlayError SetOverlayRaw( VROverlayHandle_t ulOverlayHandle, void *pvBuffer, uint32_t unWidth, uint32_t unHeight, uint32_t unDepth ) = 0;
+
+                /** Separate interface for providing the image through a filename: can be png or jpg, and should not be bigger than 1920x1080.
+                * This function can only be called by the overlay's renderer process */
+                virtual EVROverlayError SetOverlayFromFile( VROverlayHandle_t ulOverlayHandle, const char *pchFilePath ) = 0;
+
+                /** Get the native texture handle/device for an overlay you have created.
+                * On windows this handle will be a ID3D11ShaderResourceView with a ID3D11Texture2D bound.
+                *
+                * The texture will always be sized to match the backing texture you supplied in SetOverlayTexture above.
+                *
+                * You MUST call ReleaseNativeOverlayHandle() with pNativeTextureHandle once you are done with this texture.
+                *
+                * pNativeTextureHandle is an OUTPUT, it will be a pointer to a ID3D11ShaderResourceView *.
+                * pNativeTextureRef is an INPUT and should be a ID3D11Resource *. The device used by pNativeTextureRef will be used to bind pNativeTextureHandle.
+                */
+                virtual EVROverlayError GetOverlayTexture( VROverlayHandle_t ulOverlayHandle, void **pNativeTextureHandle, void *pNativeTextureRef, uint32_t *pWidth, uint32_t *pHeight, uint32_t *pNativeFormat, ETextureType *pAPIType, EColorSpace *pColorSpace, VRTextureBounds_t *pTextureBounds ) = 0;
+
+                /** Release the pNativeTextureHandle provided from the GetOverlayTexture call, this allows the system to free the underlying GPU resources for this object,
+                * so only do it once you stop rendering this texture.
+                */
+                virtual EVROverlayError ReleaseNativeOverlayHandle( VROverlayHandle_t ulOverlayHandle, void *pNativeTextureHandle ) = 0;
+
+                /** Get the size of the overlay texture */
+                virtual EVROverlayError GetOverlayTextureSize( VROverlayHandle_t ulOverlayHandle, uint32_t *pWidth, uint32_t *pHeight ) = 0;
+
+                // ----------------------------------------------
+                // Dashboard Overlay Methods
+                // ----------------------------------------------
+
+                /** Creates a dashboard overlay and returns its handle */
+                virtual EVROverlayError CreateDashboardOverlay( const char *pchOverlayKey, const char *pchOverlayFriendlyName, VROverlayHandle_t * pMainHandle, VROverlayHandle_t *pThumbnailHandle ) = 0;
+
+                /** Returns true if the dashboard is visible */
+                virtual bool IsDashboardVisible() = 0;
+
+                /** returns true if the dashboard is visible and the specified overlay is the active system Overlay */
+                virtual bool IsActiveDashboardOverlay( VROverlayHandle_t ulOverlayHandle ) = 0;
+
+                /** Sets the dashboard overlay to only appear when the specified process ID has scene focus */
+                virtual EVROverlayError SetDashboardOverlaySceneProcess( VROverlayHandle_t ulOverlayHandle, uint32_t unProcessId ) = 0;
+
+                /** Gets the process ID that this dashboard overlay requires to have scene focus */
+                virtual EVROverlayError GetDashboardOverlaySceneProcess( VROverlayHandle_t ulOverlayHandle, uint32_t *punProcessId ) = 0;
+
+                /** Shows the dashboard. */
+                virtual void ShowDashboard( const char *pchOverlayToShow ) = 0;
+
+                /** Returns the tracked device that has the laser pointer in the dashboard */
+                virtual vr::TrackedDeviceIndex_t GetPrimaryDashboardDevice() = 0;
+
+                // ---------------------------------------------
+                // Keyboard methods
+                // ---------------------------------------------
+                
+                /** Show the virtual keyboard to accept input **/
+                virtual EVROverlayError ShowKeyboard( EGamepadTextInputMode eInputMode, EGamepadTextInputLineMode eLineInputMode, const char *pchDescription, uint32_t unCharMax, const char *pchExistingText, bool bUseMinimalMode, uint64_t uUserValue ) = 0;
+
+                virtual EVROverlayError ShowKeyboardForOverlay( VROverlayHandle_t ulOverlayHandle, EGamepadTextInputMode eInputMode, EGamepadTextInputLineMode eLineInputMode, const char *pchDescription, uint32_t unCharMax, const char *pchExistingText, bool bUseMinimalMode, uint64_t uUserValue ) = 0;
+
+                /** Get the text that was entered into the text input **/
+                virtual uint32_t GetKeyboardText( VR_OUT_STRING() char *pchText, uint32_t cchText ) = 0;
+
+                /** Hide the virtual keyboard **/
+                virtual void HideKeyboard() = 0;
+
+                /** Set the position of the keyboard in world space **/
+                virtual void SetKeyboardTransformAbsolute( ETrackingUniverseOrigin eTrackingOrigin, const HmdMatrix34_t *pmatTrackingOriginToKeyboardTransform ) = 0;
+
+                /** Set the position of the keyboard in overlay space by telling it to avoid a rectangle in the overlay. Rectangle coords have (0,0) in the bottom left **/
+                virtual void SetKeyboardPositionForOverlay( VROverlayHandle_t ulOverlayHandle, HmdRect2_t avoidRect ) = 0;
+
+                // ---------------------------------------------
+                // Overlay input methods
+                // ---------------------------------------------
+
+                /** Sets a list of primitives to be used for controller ray intersection
+                * typically the size of the underlying UI in pixels (not in world space). */
+                virtual EVROverlayError SetOverlayIntersectionMask( VROverlayHandle_t ulOverlayHandle, VROverlayIntersectionMaskPrimitive_t *pMaskPrimitives, uint32_t unNumMaskPrimitives, uint32_t unPrimitiveSize = sizeof( VROverlayIntersectionMaskPrimitive_t ) ) = 0;
+
+                virtual EVROverlayError GetOverlayFlags( VROverlayHandle_t ulOverlayHandle, uint32_t *pFlags ) = 0;
+
+                // ---------------------------------------------
+                // Message box methods
+                // ---------------------------------------------
+
+                /** Show the message overlay. This will block and return you a result. **/
+                virtual VRMessageOverlayResponse ShowMessageOverlay( const char* pchText, const char* pchCaption, const char* pchButton0Text, const char* pchButton1Text = nullptr, const char* pchButton2Text = nullptr, const char* pchButton3Text = nullptr ) = 0;
+        };
+
+        static const char * const IVROverlay_Version = "IVROverlay_014";
+
+} // namespace vr
+
+// ivrrendermodels.h
+namespace vr
+{
+
+static const char * const k_pch_Controller_Component_GDC2015 = "gdc2015";   // Canonical coordinate system of the gdc 2015 wired controller, provided for backwards compatibility
+static const char * const k_pch_Controller_Component_Base = "base";         // For controllers with an unambiguous 'base'.
+static const char * const k_pch_Controller_Component_Tip = "tip";           // For controllers with an unambiguous 'tip' (used for 'laser-pointing')
+static const char * const k_pch_Controller_Component_HandGrip = "handgrip"; // Neutral, ambidextrous hand-pose when holding controller. On plane between neutrally posed index finger and thumb
+static const char * const k_pch_Controller_Component_Status = "status";         // 1:1 aspect ratio status area, with canonical [0,1] uv mapping
+
+#if defined(__linux__) || defined(__APPLE__) 
+// The 32-bit version of gcc has the alignment requirement for uint64 and double set to
+// 4 meaning that even with #pragma pack(8) these types will only be four-byte aligned.
+// The 64-bit version of gcc has the alignment requirement for these types set to
+// 8 meaning that unless we use #pragma pack(4) our structures will get bigger.
+// The 64-bit structure packing has to match the 32-bit structure packing for each platform.
+#pragma pack( push, 4 )
+#else
+#pragma pack( push, 8 )
+#endif
+
+/** Errors that can occur with the VR compositor */
+enum EVRRenderModelError
+{
+        VRRenderModelError_None = 0,
+        VRRenderModelError_Loading = 100,
+        VRRenderModelError_NotSupported = 200,
+        VRRenderModelError_InvalidArg = 300,
+        VRRenderModelError_InvalidModel = 301,
+        VRRenderModelError_NoShapes = 302,
+        VRRenderModelError_MultipleShapes = 303,
+        VRRenderModelError_TooManyVertices = 304,
+        VRRenderModelError_MultipleTextures = 305,
+        VRRenderModelError_BufferTooSmall = 306,
+        VRRenderModelError_NotEnoughNormals = 307,
+        VRRenderModelError_NotEnoughTexCoords = 308,
+
+        VRRenderModelError_InvalidTexture = 400,
+};
+
+typedef uint32_t VRComponentProperties;
+
+enum EVRComponentProperty
+{
+        VRComponentProperty_IsStatic = (1 << 0),
+        VRComponentProperty_IsVisible = (1 << 1),
+        VRComponentProperty_IsTouched = (1 << 2),
+        VRComponentProperty_IsPressed = (1 << 3),
+        VRComponentProperty_IsScrolled = (1 << 4),
+};
+
+/** Describes state information about a render-model component, including transforms and other dynamic properties */
+struct RenderModel_ComponentState_t
+{
+        HmdMatrix34_t mTrackingToComponentRenderModel;  // Transform required when drawing the component render model
+        HmdMatrix34_t mTrackingToComponentLocal;        // Transform available for attaching to a local component coordinate system (-Z out from surface )
+        VRComponentProperties uProperties;
+};
+
+/** A single vertex in a render model */
+struct RenderModel_Vertex_t
+{
+        HmdVector3_t vPosition;         // position in meters in device space
+        HmdVector3_t vNormal;
+        float rfTextureCoord[2];
+};
+
+/** A texture map for use on a render model */
+struct RenderModel_TextureMap_t
+{
+        uint16_t unWidth, unHeight; // width and height of the texture map in pixels
+        const uint8_t *rubTextureMapData;       // Map texture data. All textures are RGBA with 8 bits per channel per pixel. Data size is width * height * 4ub
+};
+
+/**  Session unique texture identifier. Rendermodels which share the same texture will have the same id.
+IDs <0 denote the texture is not present */
+
+typedef int32_t TextureID_t;
+
+const TextureID_t INVALID_TEXTURE_ID = -1;
+
+struct RenderModel_t
+{
+        const RenderModel_Vertex_t *rVertexData;        // Vertex data for the mesh
+        uint32_t unVertexCount;                                         // Number of vertices in the vertex data
+        const uint16_t *rIndexData;                                     // Indices into the vertex data for each triangle
+        uint32_t unTriangleCount;                                       // Number of triangles in the mesh. Index count is 3 * TriangleCount
+        TextureID_t diffuseTextureId;                           // Session unique texture identifier. Rendermodels which share the same texture will have the same id. <0 == texture not present
+};
+
+struct RenderModel_ControllerMode_State_t
+{
+        bool bScrollWheelVisible; // is this controller currently set to be in a scroll wheel mode
+};
+
+#pragma pack( pop )
+
+class IVRRenderModels
+{
+public:
+
+        /** Loads and returns a render model for use in the application. pchRenderModelName should be a render model name
+        * from the Prop_RenderModelName_String property or an absolute path name to a render model on disk. 
+        *
+        * The resulting render model is valid until VR_Shutdown() is called or until FreeRenderModel() is called. When the 
+        * application is finished with the render model it should call FreeRenderModel() to free the memory associated
+        * with the model.
+        *
+        * The method returns VRRenderModelError_Loading while the render model is still being loaded.
+        * The method returns VRRenderModelError_None once loaded successfully, otherwise will return an error. */
+        virtual EVRRenderModelError LoadRenderModel_Async( const char *pchRenderModelName, RenderModel_t **ppRenderModel ) = 0;
+
+        /** Frees a previously returned render model
+        *   It is safe to call this on a null ptr. */
+        virtual void FreeRenderModel( RenderModel_t *pRenderModel ) = 0;
+
+        /** Loads and returns a texture for use in the application. */
+        virtual EVRRenderModelError LoadTexture_Async( TextureID_t textureId, RenderModel_TextureMap_t **ppTexture ) = 0;
+
+        /** Frees a previously returned texture
+        *   It is safe to call this on a null ptr. */
+        virtual void FreeTexture( RenderModel_TextureMap_t *pTexture ) = 0;
+
+        /** Creates a D3D11 texture and loads data into it. */
+        virtual EVRRenderModelError LoadTextureD3D11_Async( TextureID_t textureId, void *pD3D11Device, void **ppD3D11Texture2D ) = 0;
+
+        /** Helper function to copy the bits into an existing texture. */
+        virtual EVRRenderModelError LoadIntoTextureD3D11_Async( TextureID_t textureId, void *pDstTexture ) = 0;
+
+        /** Use this to free textures created with LoadTextureD3D11_Async instead of calling Release on them. */
+        virtual void FreeTextureD3D11( void *pD3D11Texture2D ) = 0;
+
+        /** Use this to get the names of available render models.  Index does not correlate to a tracked device index, but
+        * is only used for iterating over all available render models.  If the index is out of range, this function will return 0.
+        * Otherwise, it will return the size of the buffer required for the name. */
+        virtual uint32_t GetRenderModelName( uint32_t unRenderModelIndex, VR_OUT_STRING() char *pchRenderModelName, uint32_t unRenderModelNameLen ) = 0;
+
+        /** Returns the number of available render models. */
+        virtual uint32_t GetRenderModelCount() = 0;
+
+
+        /** Returns the number of components of the specified render model.
+        *  Components are useful when client application wish to draw, label, or otherwise interact with components of tracked objects.
+        *  Examples controller components:
+        *   renderable things such as triggers, buttons
+        *   non-renderable things which include coordinate systems such as 'tip', 'base', a neutral controller agnostic hand-pose
+        *   If all controller components are enumerated and rendered, it will be equivalent to drawing the traditional render model
+        *   Returns 0 if components not supported, >0 otherwise */
+        virtual uint32_t GetComponentCount( const char *pchRenderModelName ) = 0;
+
+        /** Use this to get the names of available components.  Index does not correlate to a tracked device index, but
+        * is only used for iterating over all available components.  If the index is out of range, this function will return 0.
+        * Otherwise, it will return the size of the buffer required for the name. */
+        virtual uint32_t GetComponentName( const char *pchRenderModelName, uint32_t unComponentIndex, VR_OUT_STRING( ) char *pchComponentName, uint32_t unComponentNameLen ) = 0;
+
+        /** Get the button mask for all buttons associated with this component
+        *   If no buttons (or axes) are associated with this component, return 0
+        *   Note: multiple components may be associated with the same button. Ex: two grip buttons on a single controller.
+        *   Note: A single component may be associated with multiple buttons. Ex: A trackpad which also provides "D-pad" functionality */
+        virtual uint64_t GetComponentButtonMask( const char *pchRenderModelName, const char *pchComponentName ) = 0;
+
+        /** Use this to get the render model name for the specified rendermode/component combination, to be passed to LoadRenderModel.
+        * If the component name is out of range, this function will return 0.
+        * Otherwise, it will return the size of the buffer required for the name. */
+        virtual uint32_t GetComponentRenderModelName( const char *pchRenderModelName, const char *pchComponentName, VR_OUT_STRING( ) char *pchComponentRenderModelName, uint32_t unComponentRenderModelNameLen ) = 0;
+
+        /** Use this to query information about the component, as a function of the controller state.
+        *
+        * For dynamic controller components (ex: trigger) values will reflect component motions
+        * For static components this will return a consistent value independent of the VRControllerState_t
+        *
+        * If the pchRenderModelName or pchComponentName is invalid, this will return false (and transforms will be set to identity).
+        * Otherwise, return true
+        * Note: For dynamic objects, visibility may be dynamic. (I.e., true/false will be returned based on controller state and controller mode state ) */
+        virtual bool GetComponentState( const char *pchRenderModelName, const char *pchComponentName, const vr::VRControllerState_t *pControllerState, const RenderModel_ControllerMode_State_t *pState, RenderModel_ComponentState_t *pComponentState ) = 0;
+
+        /** Returns true if the render model has a component with the specified name */
+        virtual bool RenderModelHasComponent( const char *pchRenderModelName, const char *pchComponentName ) = 0;
+
+        /** Returns the URL of the thumbnail image for this rendermodel */
+        virtual uint32_t GetRenderModelThumbnailURL( const char *pchRenderModelName, VR_OUT_STRING() char *pchThumbnailURL, uint32_t unThumbnailURLLen, vr::EVRRenderModelError *peError ) = 0;
+
+        /** Provides a render model path that will load the unskinned model if the model name provided has been replace by the user. If the model
+        * hasn't been replaced the path value will still be a valid path to load the model. Pass this to LoadRenderModel_Async, etc. to load the
+        * model. */
+        virtual uint32_t GetRenderModelOriginalPath( const char *pchRenderModelName, VR_OUT_STRING() char *pchOriginalPath, uint32_t unOriginalPathLen, vr::EVRRenderModelError *peError ) = 0;
+
+        /** Returns a string for a render model error */
+        virtual const char *GetRenderModelErrorNameFromEnum( vr::EVRRenderModelError error ) = 0;
+};
+
+static const char * const IVRRenderModels_Version = "IVRRenderModels_005";
+
+}
+
+
+// ivrextendeddisplay.h
+namespace vr
+{
+
+        /** NOTE: Use of this interface is not recommended in production applications. It will not work for displays which use
+        * direct-to-display mode. Creating our own window is also incompatible with the VR compositor and is not available when the compositor is running. */
+        class IVRExtendedDisplay
+        {
+        public:
+
+                /** Size and position that the window needs to be on the VR display. */
+                virtual void GetWindowBounds( int32_t *pnX, int32_t *pnY, uint32_t *pnWidth, uint32_t *pnHeight ) = 0;
+
+                /** Gets the viewport in the frame buffer to draw the output of the distortion into */
+                virtual void GetEyeOutputViewport( EVREye eEye, uint32_t *pnX, uint32_t *pnY, uint32_t *pnWidth, uint32_t *pnHeight ) = 0;
+
+                /** [D3D10/11 Only]
+                * Returns the adapter index and output index that the user should pass into EnumAdapters and EnumOutputs
+                * to create the device and swap chain in DX10 and DX11. If an error occurs both indices will be set to -1.
+                */
+                virtual void GetDXGIOutputInfo( int32_t *pnAdapterIndex, int32_t *pnAdapterOutputIndex ) = 0;
+
+        };
+
+        static const char * const IVRExtendedDisplay_Version = "IVRExtendedDisplay_001";
+
+}
+
+
+// ivrtrackedcamera.h
+namespace vr
+{
+
+class IVRTrackedCamera
+{
+public:
+        /** Returns a string for an error */
+        virtual const char *GetCameraErrorNameFromEnum( vr::EVRTrackedCameraError eCameraError ) = 0;
+
+        /** For convenience, same as tracked property request Prop_HasCamera_Bool */
+        virtual vr::EVRTrackedCameraError HasCamera( vr::TrackedDeviceIndex_t nDeviceIndex, bool *pHasCamera ) = 0;
+
+        /** Gets size of the image frame. */
+        virtual vr::EVRTrackedCameraError GetCameraFrameSize( vr::TrackedDeviceIndex_t nDeviceIndex, vr::EVRTrackedCameraFrameType eFrameType, uint32_t *pnWidth, uint32_t *pnHeight, uint32_t *pnFrameBufferSize ) = 0;
+
+        virtual vr::EVRTrackedCameraError GetCameraIntrinsics( vr::TrackedDeviceIndex_t nDeviceIndex, vr::EVRTrackedCameraFrameType eFrameType, vr::HmdVector2_t *pFocalLength, vr::HmdVector2_t *pCenter ) = 0;
+
+        virtual vr::EVRTrackedCameraError GetCameraProjection( vr::TrackedDeviceIndex_t nDeviceIndex, vr::EVRTrackedCameraFrameType eFrameType, float flZNear, float flZFar, vr::HmdMatrix44_t *pProjection ) = 0;
+
+        /** Acquiring streaming service permits video streaming for the caller. Releasing hints the system that video services do not need to be maintained for this client.
+        * If the camera has not already been activated, a one time spin up may incur some auto exposure as well as initial streaming frame delays.
+        * The camera should be considered a global resource accessible for shared consumption but not exclusive to any caller.
+        * The camera may go inactive due to lack of active consumers or headset idleness. */
+        virtual vr::EVRTrackedCameraError AcquireVideoStreamingService( vr::TrackedDeviceIndex_t nDeviceIndex, vr::TrackedCameraHandle_t *pHandle ) = 0;
+        virtual vr::EVRTrackedCameraError ReleaseVideoStreamingService( vr::TrackedCameraHandle_t hTrackedCamera ) = 0;
+
+        /** Copies the image frame into a caller's provided buffer. The image data is currently provided as RGBA data, 4 bytes per pixel.
+        * A caller can provide null for the framebuffer or frameheader if not desired. Requesting the frame header first, followed by the frame buffer allows
+        * the caller to determine if the frame as advanced per the frame header sequence. 
+        * If there is no frame available yet, due to initial camera spinup or re-activation, the error will be VRTrackedCameraError_NoFrameAvailable.
+        * Ideally a caller should be polling at ~16ms intervals */
+        virtual vr::EVRTrackedCameraError GetVideoStreamFrameBuffer( vr::TrackedCameraHandle_t hTrackedCamera, vr::EVRTrackedCameraFrameType eFrameType, void *pFrameBuffer, uint32_t nFrameBufferSize, vr::CameraVideoStreamFrameHeader_t *pFrameHeader, uint32_t nFrameHeaderSize ) = 0;
+
+        /** Gets size of the image frame. */
+        virtual vr::EVRTrackedCameraError GetVideoStreamTextureSize( vr::TrackedDeviceIndex_t nDeviceIndex, vr::EVRTrackedCameraFrameType eFrameType, vr::VRTextureBounds_t *pTextureBounds, uint32_t *pnWidth, uint32_t *pnHeight ) = 0; 
+
+        /** Access a shared D3D11 texture for the specified tracked camera stream.
+        * The camera frame type VRTrackedCameraFrameType_Undistorted is not supported directly as a shared texture. It is an interior subregion of the shared texture VRTrackedCameraFrameType_MaximumUndistorted.
+        * Instead, use GetVideoStreamTextureSize() with VRTrackedCameraFrameType_Undistorted to determine the proper interior subregion bounds along with GetVideoStreamTextureD3D11() with
+        * VRTrackedCameraFrameType_MaximumUndistorted to provide the texture. The VRTrackedCameraFrameType_MaximumUndistorted will yield an image where the invalid regions are decoded
+        * by the alpha channel having a zero component. The valid regions all have a non-zero alpha component. The subregion as described by VRTrackedCameraFrameType_Undistorted 
+        * guarantees a rectangle where all pixels are valid. */
+        virtual vr::EVRTrackedCameraError GetVideoStreamTextureD3D11( vr::TrackedCameraHandle_t hTrackedCamera, vr::EVRTrackedCameraFrameType eFrameType, void *pD3D11DeviceOrResource, void **ppD3D11ShaderResourceView, vr::CameraVideoStreamFrameHeader_t *pFrameHeader, uint32_t nFrameHeaderSize ) = 0;
+
+        /** Access a shared GL texture for the specified tracked camera stream */
+        virtual vr::EVRTrackedCameraError GetVideoStreamTextureGL( vr::TrackedCameraHandle_t hTrackedCamera, vr::EVRTrackedCameraFrameType eFrameType, vr::glUInt_t *pglTextureId, vr::CameraVideoStreamFrameHeader_t *pFrameHeader, uint32_t nFrameHeaderSize ) = 0;
+        virtual vr::EVRTrackedCameraError ReleaseVideoStreamTextureGL( vr::TrackedCameraHandle_t hTrackedCamera, vr::glUInt_t glTextureId ) = 0;
+};
+
+static const char * const IVRTrackedCamera_Version = "IVRTrackedCamera_003";
+
+} // namespace vr
+
+
+// ivrscreenshots.h
+namespace vr
+{
+
+/** Errors that can occur with the VR compositor */
+enum EVRScreenshotError
+{
+        VRScreenshotError_None                                                  = 0,
+        VRScreenshotError_RequestFailed                                 = 1,
+        VRScreenshotError_IncompatibleVersion                   = 100,
+        VRScreenshotError_NotFound                                              = 101,
+        VRScreenshotError_BufferTooSmall                                = 102,
+        VRScreenshotError_ScreenshotAlreadyInProgress   = 108,
+};
+
+/** Allows the application to generate screenshots */
+class IVRScreenshots
+{
+public:
+        /** Request a screenshot of the requested type.
+         *  A request of the VRScreenshotType_Stereo type will always
+         *  work. Other types will depend on the underlying application
+         *  support.
+         *  The first file name is for the preview image and should be a
+         *  regular screenshot (ideally from the left eye). The second
+         *  is the VR screenshot in the correct format. They should be
+         *  in the same aspect ratio.  Formats per type:
+         *  VRScreenshotType_Mono: the VR filename is ignored (can be
+         *  nullptr), this is a normal flat single shot.
+         *  VRScreenshotType_Stereo:  The VR image should be a
+         *  side-by-side with the left eye image on the left.
+         *  VRScreenshotType_Cubemap: The VR image should be six square
+         *  images composited horizontally.
+         *  VRScreenshotType_StereoPanorama: above/below with left eye
+         *  panorama being the above image.  Image is typically square
+         *  with the panorama being 2x horizontal.
+         *  
+         *  Note that the VR dashboard will call this function when
+         *  the user presses the screenshot binding (currently System
+         *  Button + Trigger).  If Steam is running, the destination
+         *  file names will be in %TEMP% and will be copied into
+         *  Steam's screenshot library for the running application
+         *  once SubmitScreenshot() is called.
+         *  If Steam is not running, the paths will be in the user's
+         *  documents folder under Documents\SteamVR\Screenshots.
+         *  Other VR applications can call this to initate a
+         *  screenshot outside of user control.
+         *  The destination file names do not need an extension,
+         *  will be replaced with the correct one for the format
+         *  which is currently .png. */
+        virtual vr::EVRScreenshotError RequestScreenshot( vr::ScreenshotHandle_t *pOutScreenshotHandle, vr::EVRScreenshotType type, const char *pchPreviewFilename, const char *pchVRFilename ) = 0;
+
+        /** Called by the running VR application to indicate that it
+         *  wishes to be in charge of screenshots.  If the
+         *  application does not call this, the Compositor will only
+         *  support VRScreenshotType_Stereo screenshots that will be
+         *  captured without notification to the running app.
+         *  Once hooked your application will receive a
+         *  VREvent_RequestScreenshot event when the user presses the
+         *  buttons to take a screenshot. */
+        virtual vr::EVRScreenshotError HookScreenshot( VR_ARRAY_COUNT( numTypes ) const vr::EVRScreenshotType *pSupportedTypes, int numTypes ) = 0;
+
+        /** When your application receives a
+         *  VREvent_RequestScreenshot event, call these functions to get
+         *  the details of the screenshot request. */
+        virtual vr::EVRScreenshotType GetScreenshotPropertyType( vr::ScreenshotHandle_t screenshotHandle, vr::EVRScreenshotError *pError ) = 0;
+
+        /** Get the filename for the preview or vr image (see
+         *  vr::EScreenshotPropertyFilenames).  The return value is
+         *  the size of the string.   */
+        virtual uint32_t GetScreenshotPropertyFilename( vr::ScreenshotHandle_t screenshotHandle, vr::EVRScreenshotPropertyFilenames filenameType, VR_OUT_STRING() char *pchFilename, uint32_t cchFilename, vr::EVRScreenshotError *pError ) = 0;
+
+        /** Call this if the application is taking the screen shot
+         *  will take more than a few ms processing. This will result
+         *  in an overlay being presented that shows a completion
+         *  bar. */
+        virtual vr::EVRScreenshotError UpdateScreenshotProgress( vr::ScreenshotHandle_t screenshotHandle, float flProgress ) = 0;
+
+        /** Tells the compositor to take an internal screenshot of
+         *  type VRScreenshotType_Stereo. It will take the current
+         *  submitted scene textures of the running application and
+         *  write them into the preview image and a side-by-side file
+         *  for the VR image.
+         *  This is similiar to request screenshot, but doesn't ever
+         *  talk to the application, just takes the shot and submits. */
+        virtual vr::EVRScreenshotError TakeStereoScreenshot( vr::ScreenshotHandle_t *pOutScreenshotHandle, const char *pchPreviewFilename, const char *pchVRFilename ) = 0;
+
+        /** Submit the completed screenshot.  If Steam is running
+         *  this will call into the Steam client and upload the
+         *  screenshot to the screenshots section of the library for
+         *  the running application.  If Steam is not running, this
+         *  function will display a notification to the user that the
+         *  screenshot was taken. The paths should be full paths with
+         *  extensions.
+         *  File paths should be absolute including
+         *  exntensions.
+         *  screenshotHandle can be k_unScreenshotHandleInvalid if this
+         *  was a new shot taking by the app to be saved and not
+         *  initiated by a user (achievement earned or something) */
+        virtual vr::EVRScreenshotError SubmitScreenshot( vr::ScreenshotHandle_t screenshotHandle, vr::EVRScreenshotType type, const char *pchSourcePreviewFilename, const char *pchSourceVRFilename ) = 0;
+};
+
+static const char * const IVRScreenshots_Version = "IVRScreenshots_001";
+
+} // namespace vr
+
+
+
+// ivrresources.h
+namespace vr
+{
+
+class IVRResources
+{
+public:
+
+        // ------------------------------------
+        // Shared Resource Methods
+        // ------------------------------------
+
+        /** Loads the specified resource into the provided buffer if large enough.
+        * Returns the size in bytes of the buffer required to hold the specified resource. */
+        virtual uint32_t LoadSharedResource( const char *pchResourceName, char *pchBuffer, uint32_t unBufferLen ) = 0;
+
+        /** Provides the full path to the specified resource. Resource names can include named directories for
+        * drivers and other things, and this resolves all of those and returns the actual physical path. 
+        * pchResourceTypeDirectory is the subdirectory of resources to look in. */
+        virtual uint32_t GetResourceFullPath( const char *pchResourceName, const char *pchResourceTypeDirectory, char *pchPathBuffer, uint32_t unBufferLen ) = 0;
+};
+
+static const char * const IVRResources_Version = "IVRResources_001";
+
+
+}// End
+
+#endif // _OPENVR_API
+
+
+namespace vr
+{
+        /** Finds the active installation of the VR API and initializes it. The provided path must be absolute
+        * or relative to the current working directory. These are the local install versions of the equivalent
+        * functions in steamvr.h and will work without a local Steam install.
+        *
+        * This path is to the "root" of the VR API install. That's the directory with
+        * the "drivers" directory and a platform (i.e. "win32") directory in it, not the directory with the DLL itself.
+        */
+        inline IVRSystem *VR_Init( EVRInitError *peError, EVRApplicationType eApplicationType );
+
+        /** unloads vrclient.dll. Any interface pointers from the interface are
+        * invalid after this point */
+        inline void VR_Shutdown();
+
+        /** Returns true if there is an HMD attached. This check is as lightweight as possible and
+        * can be called outside of VR_Init/VR_Shutdown. It should be used when an application wants
+        * to know if initializing VR is a possibility but isn't ready to take that step yet.
+        */
+        VR_INTERFACE bool VR_CALLTYPE VR_IsHmdPresent();
+
+        /** Returns true if the OpenVR runtime is installed. */
+        VR_INTERFACE bool VR_CALLTYPE VR_IsRuntimeInstalled();
+
+        /** Returns where the OpenVR runtime is installed. */
+        VR_INTERFACE const char *VR_CALLTYPE VR_RuntimePath();
+
+        /** Returns the name of the enum value for an EVRInitError. This function may be called outside of VR_Init()/VR_Shutdown(). */
+        VR_INTERFACE const char *VR_CALLTYPE VR_GetVRInitErrorAsSymbol( EVRInitError error );
+
+        /** Returns an english string for an EVRInitError. Applications should call VR_GetVRInitErrorAsSymbol instead and
+        * use that as a key to look up their own localized error message. This function may be called outside of VR_Init()/VR_Shutdown(). */
+        VR_INTERFACE const char *VR_CALLTYPE VR_GetVRInitErrorAsEnglishDescription( EVRInitError error );
+
+        /** Returns the interface of the specified version. This method must be called after VR_Init. The
+        * pointer returned is valid until VR_Shutdown is called.
+        */
+        VR_INTERFACE void *VR_CALLTYPE VR_GetGenericInterface( const char *pchInterfaceVersion, EVRInitError *peError );
+
+        /** Returns whether the interface of the specified version exists.
+        */
+        VR_INTERFACE bool VR_CALLTYPE VR_IsInterfaceVersionValid( const char *pchInterfaceVersion );
+
+        /** Returns a token that represents whether the VR interface handles need to be reloaded */
+        VR_INTERFACE uint32_t VR_CALLTYPE VR_GetInitToken();
+
+        // These typedefs allow old enum names from SDK 0.9.11 to be used in applications.
+        // They will go away in the future.
+        typedef EVRInitError HmdError;
+        typedef EVREye Hmd_Eye;
+        typedef EColorSpace ColorSpace;
+        typedef ETrackingResult HmdTrackingResult;
+        typedef ETrackedDeviceClass TrackedDeviceClass;
+        typedef ETrackingUniverseOrigin TrackingUniverseOrigin;
+        typedef ETrackedDeviceProperty TrackedDeviceProperty;
+        typedef ETrackedPropertyError TrackedPropertyError;
+        typedef EVRSubmitFlags VRSubmitFlags_t;
+        typedef EVRState VRState_t;
+        typedef ECollisionBoundsStyle CollisionBoundsStyle_t;
+        typedef EVROverlayError VROverlayError;
+        typedef EVRFirmwareError VRFirmwareError;
+        typedef EVRCompositorError VRCompositorError;
+        typedef EVRScreenshotError VRScreenshotsError;
+
+        inline uint32_t &VRToken()
+        {
+                static uint32_t token;
+                return token;
+        }
+
+        class COpenVRContext
+        {
+        public:
+                COpenVRContext() { Clear(); }
+                void Clear();
+
+                inline void CheckClear()
+                {
+                        if ( VRToken() != VR_GetInitToken() )
+                        {
+                                Clear();
+                                VRToken() = VR_GetInitToken();
+                        }
+                }
+
+                IVRSystem *VRSystem()
+                {
+                        CheckClear();
+                        if ( m_pVRSystem == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRSystem = ( IVRSystem * )VR_GetGenericInterface( IVRSystem_Version, &eError );
+                        }
+                        return m_pVRSystem;
+                }
+                IVRChaperone *VRChaperone()
+                {
+                        CheckClear();
+                        if ( m_pVRChaperone == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRChaperone = ( IVRChaperone * )VR_GetGenericInterface( IVRChaperone_Version, &eError );
+                        }
+                        return m_pVRChaperone;
+                }
+
+                IVRChaperoneSetup *VRChaperoneSetup()
+                {
+                        CheckClear();
+                        if ( m_pVRChaperoneSetup == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRChaperoneSetup = ( IVRChaperoneSetup * )VR_GetGenericInterface( IVRChaperoneSetup_Version, &eError );
+                        }
+                        return m_pVRChaperoneSetup;
+                }
+
+                IVRCompositor *VRCompositor()
+                {
+                        CheckClear();
+                        if ( m_pVRCompositor == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRCompositor = ( IVRCompositor * )VR_GetGenericInterface( IVRCompositor_Version, &eError );
+                        }
+                        return m_pVRCompositor;
+                }
+
+                IVROverlay *VROverlay()
+                {
+                        CheckClear();
+                        if ( m_pVROverlay == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVROverlay = ( IVROverlay * )VR_GetGenericInterface( IVROverlay_Version, &eError );
+                        }
+                        return m_pVROverlay;
+                }
+
+                IVRResources *VRResources()
+                {
+                        CheckClear();
+                        if ( m_pVRResources == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRResources = (IVRResources *)VR_GetGenericInterface( IVRResources_Version, &eError );
+                        }
+                        return m_pVRResources;
+                }
+
+                IVRScreenshots *VRScreenshots()
+                {
+                        CheckClear();
+                        if ( m_pVRScreenshots == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRScreenshots = ( IVRScreenshots * )VR_GetGenericInterface( IVRScreenshots_Version, &eError );
+                        }
+                        return m_pVRScreenshots;
+                }
+
+                IVRRenderModels *VRRenderModels()
+                {
+                        CheckClear();
+                        if ( m_pVRRenderModels == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRRenderModels = ( IVRRenderModels * )VR_GetGenericInterface( IVRRenderModels_Version, &eError );
+                        }
+                        return m_pVRRenderModels;
+                }
+
+                IVRExtendedDisplay *VRExtendedDisplay()
+                {
+                        CheckClear();
+                        if ( m_pVRExtendedDisplay == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRExtendedDisplay = ( IVRExtendedDisplay * )VR_GetGenericInterface( IVRExtendedDisplay_Version, &eError );
+                        }
+                        return m_pVRExtendedDisplay;
+                }
+
+                IVRSettings *VRSettings()
+                {
+                        CheckClear();
+                        if ( m_pVRSettings == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRSettings = ( IVRSettings * )VR_GetGenericInterface( IVRSettings_Version, &eError );
+                        }
+                        return m_pVRSettings;
+                }
+
+                IVRApplications *VRApplications()
+                {
+                        CheckClear();
+                        if ( m_pVRApplications == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRApplications = ( IVRApplications * )VR_GetGenericInterface( IVRApplications_Version, &eError );
+                        }
+                        return m_pVRApplications;
+                }
+
+                IVRTrackedCamera *VRTrackedCamera()
+                {
+                        CheckClear();
+                        if ( m_pVRTrackedCamera == nullptr )
+                        {
+                                EVRInitError eError;
+                                m_pVRTrackedCamera = ( IVRTrackedCamera * )VR_GetGenericInterface( IVRTrackedCamera_Version, &eError );
+                        }
+                        return m_pVRTrackedCamera;
+                }
+
+        private:
+                IVRSystem                       *m_pVRSystem;
+                IVRChaperone            *m_pVRChaperone;
+                IVRChaperoneSetup       *m_pVRChaperoneSetup;
+                IVRCompositor           *m_pVRCompositor;
+                IVROverlay                      *m_pVROverlay;
+                IVRResources            *m_pVRResources;
+                IVRRenderModels         *m_pVRRenderModels;
+                IVRExtendedDisplay      *m_pVRExtendedDisplay;
+                IVRSettings                     *m_pVRSettings;
+                IVRApplications         *m_pVRApplications;
+                IVRTrackedCamera        *m_pVRTrackedCamera;
+                IVRScreenshots          *m_pVRScreenshots;
+        };
+
+        inline COpenVRContext &OpenVRInternal_ModuleContext()
+        {
+                static void *ctx[ sizeof( COpenVRContext ) / sizeof( void * ) ];
+                return *( COpenVRContext * )ctx; // bypass zero-init constructor
+        }
+
+        inline IVRSystem *VR_CALLTYPE VRSystem() { return OpenVRInternal_ModuleContext().VRSystem(); }
+        inline IVRChaperone *VR_CALLTYPE VRChaperone() { return OpenVRInternal_ModuleContext().VRChaperone(); }
+        inline IVRChaperoneSetup *VR_CALLTYPE VRChaperoneSetup() { return OpenVRInternal_ModuleContext().VRChaperoneSetup(); }
+        inline IVRCompositor *VR_CALLTYPE VRCompositor() { return OpenVRInternal_ModuleContext().VRCompositor(); }
+        inline IVROverlay *VR_CALLTYPE VROverlay() { return OpenVRInternal_ModuleContext().VROverlay(); }
+        inline IVRScreenshots *VR_CALLTYPE VRScreenshots() { return OpenVRInternal_ModuleContext().VRScreenshots(); }
+        inline IVRRenderModels *VR_CALLTYPE VRRenderModels() { return OpenVRInternal_ModuleContext().VRRenderModels(); }
+        inline IVRApplications *VR_CALLTYPE VRApplications() { return OpenVRInternal_ModuleContext().VRApplications(); }
+        inline IVRSettings *VR_CALLTYPE VRSettings() { return OpenVRInternal_ModuleContext().VRSettings(); }
+        inline IVRResources *VR_CALLTYPE VRResources() { return OpenVRInternal_ModuleContext().VRResources(); }
+        inline IVRExtendedDisplay *VR_CALLTYPE VRExtendedDisplay() { return OpenVRInternal_ModuleContext().VRExtendedDisplay(); }
+        inline IVRTrackedCamera *VR_CALLTYPE VRTrackedCamera() { return OpenVRInternal_ModuleContext().VRTrackedCamera(); }
+
+        inline void COpenVRContext::Clear()
+        {
+                m_pVRSystem = nullptr;
+                m_pVRChaperone = nullptr;
+                m_pVRChaperoneSetup = nullptr;
+                m_pVRCompositor = nullptr;
+                m_pVROverlay = nullptr;
+                m_pVRRenderModels = nullptr;
+                m_pVRExtendedDisplay = nullptr;
+                m_pVRSettings = nullptr;
+                m_pVRApplications = nullptr;
+                m_pVRTrackedCamera = nullptr;
+                m_pVRResources = nullptr;
+                m_pVRScreenshots = nullptr;
+        }
+
+        VR_INTERFACE uint32_t VR_CALLTYPE VR_InitInternal( EVRInitError *peError, EVRApplicationType eApplicationType );
+        VR_INTERFACE void VR_CALLTYPE VR_ShutdownInternal();
+
+        /** Finds the active installation of vrclient.dll and initializes it */
+        inline IVRSystem *VR_Init( EVRInitError *peError, EVRApplicationType eApplicationType )
+        {
+                IVRSystem *pVRSystem = nullptr;
+
+                EVRInitError eError;
+                VRToken() = VR_InitInternal( &eError, eApplicationType );
+                COpenVRContext &ctx = OpenVRInternal_ModuleContext();
+                ctx.Clear();
+
+                if ( eError == VRInitError_None )
+                {
+                        if ( VR_IsInterfaceVersionValid( IVRSystem_Version ) )
+                        {
+                                pVRSystem = VRSystem();
+                        }
+                        else
+                        {
+                                VR_ShutdownInternal();
+                                eError = VRInitError_Init_InterfaceNotFound;
+                        }
+                }
+
+                if ( peError )
+                        *peError = eError;
+                return pVRSystem;
+        }
+
+        /** unloads vrclient.dll. Any interface pointers from the interface are
+        * invalid after this point */
+        inline void VR_Shutdown()
+        {
+                VR_ShutdownInternal();
+        }
+}