Add ability to query and allocate zero copy buffers.

ui/ozone/public/surface_factory_ozone.h

 // Copyright (c) 2013 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 UI_OZONE_PUBLIC_SURFACE_FACTORY_OZONE_H_
 #define UI_OZONE_PUBLIC_SURFACE_FACTORY_OZONE_H_
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/native_library.h"
@@ skipping 50 matching lines @@
   // Describes overlay buffer format.
   // TODO: this is a placeholder for now and will be populated with more
   // formats once we know what sorts of content, video, etc. we can support.
   enum BufferFormat {
     UNKNOWN,
     RGBA_8888,
     RGBX_8888,
     RGB_888,
   };
 
+  enum BufferUsage {
+    MAP,

[spang, 2014/11/07 17:42:06]

do we ever want both (MAP | SCANOUT)?

+    SCANOUT,
+  };
+
   typedef void* (*GLGetProcAddressProc)(const char* name);
   typedef base::Callback<void(base::NativeLibrary)> AddGLLibraryCallback;
   typedef base::Callback<void(GLGetProcAddressProc)>
       SetGLGetProcAddressProcCallback;
 
   SurfaceFactoryOzone();
   virtual ~SurfaceFactoryOzone();
 
   // Returns the singleton instance.
   static SurfaceFactoryOzone* GetInstance();
@@ skipping 33 matching lines @@
   // used to select a display configuration. Note that all properties should be
   // immediately followed by the corresponding desired value and array should be
   // terminated with EGL_NONE. Ownership of the array is not transferred to
   // caller. desired_list contains list of desired EGL properties and values.
   virtual const int32* GetEGLSurfaceProperties(const int32* desired_list);
 
   // Get the hal struct to check for overlay support.
   virtual OverlayCandidatesOzone* GetOverlayCandidates(
       gfx::AcceleratedWidget w);
 
-  // Cleate a single native buffer to be used for overlay planes.
-  virtual scoped_refptr<NativePixmap> CreateNativePixmap(
-      gfx::Size size,
-      BufferFormat format);
+  // Cleate a single native buffer to be used for overlay planes or zero copy.
+  virtual scoped_refptr<NativePixmap> CreateNativePixmap(gfx::Size size,
+                                                         BufferFormat format,
+                                                         BufferUsage usage);
 
   // Sets the overlay plane to switch to at the next page flip.
   // |w| specifies the screen to display this overlay plane on.
   // |plane_z_order| specifies the stacking order of the plane relative to the
   // main framebuffer located at index 0.
   // |plane_transform| specifies how the buffer is to be transformed during.
   // composition.
   // |buffer| to be presented by the overlay.
   // |display_bounds| specify where it is supposed to be on the screen.
   // |crop_rect| specifies the region within the buffer to be placed
   // inside |display_bounds|. This is specified in texture coordinates, in the
   // range of [0,1].
   virtual bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                                     int plane_z_order,
                                     gfx::OverlayTransform plane_transform,
                                     scoped_refptr<NativePixmap> buffer,
                                     const gfx::Rect& display_bounds,
                                     const gfx::RectF& crop_rect);
 
   // Returns true if overlays can be shown at z-index 0, replacing the main
   // surface. Combined with surfaceless extensions, it allows for an
   // overlay-only mode.
   virtual bool CanShowPrimaryPlaneAsOverlay();
 
+  // Returns true if the platform is able to create buffers for a specific usage
+  // such as MAP for zero copy or SCANOUT for display controller.
+  virtual bool CanCreateNativePixmap(BufferUsage usage);
+
  private:
   static SurfaceFactoryOzone* impl_;  // not owned
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PUBLIC_SURFACE_FACTORY_OZONE_H_