cc/output/output_surface.h

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_OUTPUT_OUTPUT_SURFACE_H_
   6 #define CC_OUTPUT_OUTPUT_SURFACE_H_
   7
   8 #include <deque>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "cc/base/cc_export.h"
  15 #include "cc/output/context_provider.h"
  16 #include "cc/output/overlay_candidate_validator.h"
  17 #include "cc/output/software_output_device.h"
  18
  19 namespace base { class SingleThreadTaskRunner; }
  20
  21 namespace ui { struct LatencyInfo; }
  22
  23 namespace gfx {
  24 class Rect;
  25 class Size;
  26 class Transform;
  27 }
  28
  29 namespace cc {
  30
  31 class CompositorFrame;
  32 class CompositorFrameAck;
  33 struct ManagedMemoryPolicy;
  34 class OutputSurfaceClient;
  35
  36 // Represents the output surface for a compositor. The compositor owns
  37 // and manages its destruction. Its lifetime is:
  38 //   1. Created on the main thread by the LayerTreeHost through its client.
  39 //   2. Passed to the compositor thread and bound to a client via BindToClient.
  40 //      From here on, it will only be used on the compositor thread.
  41 //   3. If the 3D context is lost, then the compositor will delete the output
  42 //      surface (on the compositor thread) and go back to step 1.
  43 class CC_EXPORT OutputSurface {
  44  public:
  45   enum {
  46     DEFAULT_MAX_FRAMES_PENDING = 2
  47   };
  48
  49   explicit OutputSurface(
  50       const scoped_refptr<ContextProvider>& context_provider);
  51
  52   explicit OutputSurface(scoped_ptr<SoftwareOutputDevice> software_device);
  53
  54   OutputSurface(const scoped_refptr<ContextProvider>& context_provider,
  55                 scoped_ptr<SoftwareOutputDevice> software_device);
  56
  57   virtual ~OutputSurface();
  58
  59   struct Capabilities {
  60     Capabilities()
  61         : delegated_rendering(false),
  62           max_frames_pending(0),
  63           deferred_gl_initialization(false),
  64           draw_and_swap_full_viewport_every_frame(false),
  65           adjust_deadline_for_parent(true),
  66           uses_default_gl_framebuffer(true),
  67           flipped_output_surface(false) {}
  68     bool delegated_rendering;
  69     int max_frames_pending;
  70     bool deferred_gl_initialization;
  71     bool draw_and_swap_full_viewport_every_frame;
  72     // This doesn't handle the <webview> case, but once BeginFrame is
  73     // supported natively, we shouldn't need adjust_deadline_for_parent.
  74     bool adjust_deadline_for_parent;
  75     // Whether this output surface renders to the default OpenGL zero
  76     // framebuffer or to an offscreen framebuffer.
  77     bool uses_default_gl_framebuffer;
  78     // Whether this OutputSurface is flipped or not.
  79     bool flipped_output_surface;
  80   };
  81
  82   const Capabilities& capabilities() const {
  83     return capabilities_;
  84   }
  85
  86   virtual bool HasExternalStencilTest() const;
  87
  88   // Obtain the 3d context or the software device associated with this output
  89   // surface. Either of these may return a null pointer, but not both.
  90   // In the event of a lost context, the entire output surface should be
  91   // recreated.
  92   ContextProvider* context_provider() const { return context_provider_.get(); }
  93   SoftwareOutputDevice* software_device() const {
  94     return software_device_.get();
  95   }
  96
  97   // Called by the compositor on the compositor thread. This is a place where
  98   // thread-specific data for the output surface can be initialized, since from
  99   // this point on the output surface will only be used on the compositor
 100   // thread.
 101   virtual bool BindToClient(OutputSurfaceClient* client);
 102
 103   // This is called by the compositor on the compositor thread inside ReleaseGL
 104   // in order to release the ContextProvider. Only used with
 105   // deferred_gl_initialization capability.
 106   void ReleaseContextProvider();
 107
 108   virtual void EnsureBackbuffer();
 109   virtual void DiscardBackbuffer();
 110
 111   virtual void Reshape(const gfx::Size& size, float scale_factor);
 112   virtual gfx::Size SurfaceSize() const;
 113
 114   virtual void BindFramebuffer();
 115
 116   // The implementation may destroy or steal the contents of the CompositorFrame
 117   // passed in (though it will not take ownership of the CompositorFrame
 118   // itself). For successful swaps, the implementation must call
 119   // OutputSurfaceClient::DidSwapBuffers() and eventually
 120   // DidSwapBuffersComplete().
 121   virtual void SwapBuffers(CompositorFrame* frame) = 0;
 122   virtual void OnSwapBuffersComplete();
 123
 124   // Notifies frame-rate smoothness preference. If true, all non-critical
 125   // processing should be stopped, or lowered in priority.
 126   virtual void UpdateSmoothnessTakesPriority(bool prefer_smoothness) {}
 127
 128   bool HasClient() { return !!client_; }
 129
 130   // Get the class capable of informing cc of hardware overlay capability.
 131   OverlayCandidateValidator* overlay_candidate_validator() const {
 132     return overlay_candidate_validator_.get();
 133   }
 134
 135   void DidLoseOutputSurface();
 136   void SetMemoryPolicy(const ManagedMemoryPolicy& policy);
 137
 138  protected:
 139   OutputSurfaceClient* client_;
 140
 141   // Synchronously initialize context3d and enter hardware mode.
 142   // This can only supported in threaded compositing mode.
 143   bool InitializeAndSetContext3d(
 144       scoped_refptr<ContextProvider> context_provider);
 145   void ReleaseGL();
 146
 147   void PostSwapBuffersComplete();
 148
 149   struct OutputSurface::Capabilities capabilities_;
 150   scoped_refptr<ContextProvider> context_provider_;
 151   scoped_ptr<SoftwareOutputDevice> software_device_;
 152   scoped_ptr<OverlayCandidateValidator> overlay_candidate_validator_;
 153   gfx::Size surface_size_;
 154   float device_scale_factor_;
 155
 156   void CommitVSyncParameters(base::TimeTicks timebase,
 157                              base::TimeDelta interval);
 158
 159   void SetNeedsRedrawRect(const gfx::Rect& damage_rect);
 160   void ReclaimResources(const CompositorFrameAck* ack);
 161   void SetExternalStencilTest(bool enabled);
 162   void SetExternalDrawConstraints(
 163       const gfx::Transform& transform,
 164       const gfx::Rect& viewport,
 165       const gfx::Rect& clip,
 166       const gfx::Rect& viewport_rect_for_tile_priority,
 167       const gfx::Transform& transform_for_tile_priority,
 168       bool resourceless_software_draw);
 169
 170  private:
 171   void SetUpContext3d();
 172   void ResetContext3d();
 173
 174   bool external_stencil_test_enabled_;
 175
 176   base::WeakPtrFactory<OutputSurface> weak_ptr_factory_;
 177
 178   DISALLOW_COPY_AND_ASSIGN(OutputSurface);
 179 };
 180
 181 }  // namespace cc
 182
 183 #endif  // CC_OUTPUT_OUTPUT_SURFACE_H_