Controller support for VrShell

chrome/browser/android/vr_shell/vr_controller.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_ANDROID_VR_SHELL_VR_CONTROLLER_H_
+#define CHROME_BROWSER_ANDROID_VR_SHELL_VR_CONTROLLER_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/task_runner_util.h"
+#include "content/public/browser/android/content_view_core.h"
+#include "content/public/browser/android/vr_gesture.h"
+#include "third_party/gvr-android-sdk/src/ndk-beta/include/vr/gvr/capi/include/gvr.h"
+#include "third_party/gvr-android-sdk/src/ndk-beta/include/vr/gvr/capi/include/gvr_controller.h"
+#include "third_party/gvr-android-sdk/src/ndk-beta/include/vr/gvr/capi/include/gvr_types.h"
+
+namespace vr_shell {
+
+namespace {

[bshe, 2016/09/21 15:18:41]

nit: move this to .cc

[asimjour, 2016/09/22 14:48:36]

Done.

+constexpr float kNanoSecondsPerSecond = 1.0e9f;
+constexpr float kDisplacementScaleFactor = 800.0f;
+// A slop represents a small rectangular region around the first touch point of

[mthiesse, 2016/09/21 16:13:44]

nit: New line before comment, throughout this CL.

[asimjour, 2016/09/22 14:48:36]

Done.

+// a gesture.
+// If the user does not move outside of the slop, no gesture is detected.
+// Gestures start to be detected when the user moves outside of the slop.
+// Vertical distance from the border to the center of slop.
+constexpr float kSlopVertical = 0.165f;
+// Horizontal distance from the border to the center of slop.
+constexpr float kSlopHorizontal = 0.125f;
+constexpr float kDelta = 1.0e-7f;
+constexpr float kCutoffHz = 10.0f;
+constexpr float kRc = static_cast<float>(1.0 / (2.0 * M_PI * kCutoffHz));

[mthiesse, 2016/09/21 16:13:44]

nit: kRC

[asimjour, 2016/09/22 14:48:35]

Done.

+
+}  // namespace
+
+class VrController {
+ public:
+  // Controller API entry point.
+  explicit VrController(gvr_context_* gvr_context);
+  ~VrController();
+
+  // Must be called when the Activity gets onResume().

[mthiesse, 2016/09/21 16:13:44]

nit: OnResume()

below too.

[asimjour, 2016/09/22 14:48:35]

Done.

+  void OnResume();
+
+  // Must be called when the Activity gets onPause().
+  void OnPause();
+
+  // Must be called when the GL renderer gets onSurfaceCreated().
+  void Initialize(gvr_context_* gvr_context);
+
+  // Must be called when the GL renderer gets onDrawFrame().
+  void UpdateState();
+  VrGesture DetectGesture();
+
+  bool IsTouching();
+
+  float TouchPosX();
+
+  float TouchPosY();
+
+  const quatf Orientation();
+
+  bool IsTouchDown();
+
+  bool IsTouchUp();
+
+  bool ButtonUp(const int32_t button);
+  bool ButtonDown(const int32_t button);
+
+  bool IsConnected();
+
+ private:
+  enum gesture_detector_state {
+    WAITING,   //  waiting for user to touch down

[mthiesse, 2016/09/21 16:13:44]

nit: extra space

[asimjour, 2016/09/22 14:48:36]

Done.

+    TOUCHING,  // touching the touch pad but not scrolling
+    SCROLLING  // scrolling on the touch pad
+  };
+
+  struct TouchPoint {
+    vec2f position;
+    int64_t timestamp;
+  };
+
+  struct TouchInfo {
+    TouchPoint touch_point;
+    bool touch_up;
+    bool touch_down;
+    bool is_touching;
+  };
+
+  struct ButtonInfo {
+    gvr_controller_button button;
+    bool button_up;
+    bool button_down;
+    bool button_state;
+    int64_t timestamp;
+  };
+
+  // State of gesture detector.
+  gesture_detector_state state_;
+
+  std::unique_ptr<gvr::ControllerApi> controller_api_;
+  // The last controller state (updated once per frame).
+  gvr::ControllerState controller_state_;
+
+  float last_qx;

[mthiesse, 2016/09/21 16:13:44]

nit: trailing underscore

Also below.

[asimjour, 2016/09/22 14:48:35]

Done.

+  float last_qz;
+  bool pinch_started;
+  bool zoom_in_progress;
+
+  std::vector<VrGesture> gesture_list_;
+  std::unique_ptr<TouchInfo> touch_info_;
+
+  // A pointer storing the touch point from previous frame.
+  std::unique_ptr<TouchPoint> prev_touch_point_;
+
+  // A pointer storing the touch point from current frame.
+  std::unique_ptr<TouchPoint> cur_touch_point_;
+
+  // Initial touch point.
+  std::unique_ptr<TouchPoint> init_touch_point_;
+  // Overall velocity
+  vec2f overall_velocity_;
+
+  void UpdateGestureFromTouchInfo();

[mthiesse, 2016/09/21 16:13:44]

nit: Functions before member variables.

[asimjour, 2016/09/22 14:48:36]

Done.

+
+  bool GetButtonLongPressFromButtonInfo();
+
+  // Handle the waiting state.
+  void HandleWaitingState();
+
+  // Handle the detecting state.
+  void HandleDetectingState();
+
+  // Handle the scrolling state.
+  void HandleScrollingState();
+  void Update(const gvr_controller_state* controller_state);
+  void Update(bool touch_up,
+              bool touch_down,
+              bool is_touching,
+              const vec2f position,
+              int64_t timestamp);
+  // Returns true if the touch position is with in the slop of the initial touch
+  // point,
+  // false otherwise.
+  bool InSlop(const vec2f touch_position);
+
+  void Reset();
+
+  int GetGestureListSize() { return static_cast<int>(gesture_list_.size()); }
+
+  const VrGesture* GetGesturePtr(const int index);
+
+  // Update gesture parameters,
+  void UpdateGesture(VrGesture* gesture);
+
+  // If the user is touching the touch pad and the touch point is different from
+  // before,

[mthiesse, 2016/09/21 16:13:44]

nit: no line break

[asimjour, 2016/09/22 14:48:36]

Done.

+  // update the touch point and return true.
+  // Otherwise, return false.
+  bool UpdateCurrentTouchpoint();
+};
+
+}  // namespace vr_shell
+
+#endif  // CHROME_BROWSER_ANDROID_VR_SHELL_VR_CONTROLLER_H_