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     bool delegated_rendering;
  68     int max_frames_pending;
  69     bool deferred_gl_initialization;
  70     bool draw_and_swap_full_viewport_every_frame;
  71     // This doesn't handle the <webview> case, but once BeginFrame is
  72     // supported natively, we shouldn't need adjust_deadline_for_parent.
  73     bool adjust_deadline_for_parent;
  74     // Whether this output surface renders to the default OpenGL zero
  75     // framebuffer or to an offscreen framebuffer.
  76     bool uses_default_gl_framebuffer;
  77   };
  78
  79   const Capabilities& capabilities() const {
  80     return capabilities_;
  81   }
  82
  83   virtual bool HasExternalStencilTest() const;
  84
  85   // Obtain the 3d context or the software device associated with this output
  86   // surface. Either of these may return a null pointer, but not both.
  87   // In the event of a lost context, the entire output surface should be
  88   // recreated.
  89   ContextProvider* context_provider() const { return context_provider_.get(); }
  90   SoftwareOutputDevice* software_device() const {
  91     return software_device_.get();
  92   }
  93
  94   // Called by the compositor on the compositor thread. This is a place where
  95   // thread-specific data for the output surface can be initialized, since from
  96   // this point on the output surface will only be used on the compositor
  97   // thread.
  98   virtual bool BindToClient(OutputSurfaceClient* client);
  99
 100   // This is called by the compositor on the compositor thread inside ReleaseGL
 101   // in order to release the ContextProvider. Only used with
 102   // deferred_gl_initialization capability.
 103   void ReleaseContextProvider();
 104
 105   virtual void EnsureBackbuffer();
 106   virtual void DiscardBackbuffer();
 107
 108   virtual void Reshape(const gfx::Size& size, float scale_factor);
 109   virtual gfx::Size SurfaceSize() const;
 110
 111   virtual void BindFramebuffer();
 112
 113   // The implementation may destroy or steal the contents of the CompositorFrame
 114   // passed in (though it will not take ownership of the CompositorFrame
 115   // itself).
 116   virtual void SwapBuffers(CompositorFrame* frame);
 117   virtual void OnSwapBuffersComplete();
 118
 119   // Notifies frame-rate smoothness preference. If true, all non-critical
 120   // processing should be stopped, or lowered in priority.
 121   virtual void UpdateSmoothnessTakesPriority(bool prefer_smoothness) {}
 122
 123   // Requests a BeginFrame notification from the output surface. The
 124   // notification will be delivered by calling
 125   // OutputSurfaceClient::BeginFrame until the callback is disabled.
 126   virtual void SetNeedsBeginFrame(bool enable) {}
 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  protected:
 136   OutputSurfaceClient* client_;
 137
 138   // Synchronously initialize context3d and enter hardware mode.
 139   // This can only supported in threaded compositing mode.
 140   bool InitializeAndSetContext3d(
 141       scoped_refptr<ContextProvider> context_provider);
 142   void ReleaseGL();
 143
 144   void PostSwapBuffersComplete();
 145
 146   struct OutputSurface::Capabilities capabilities_;
 147   scoped_refptr<ContextProvider> context_provider_;
 148   scoped_ptr<SoftwareOutputDevice> software_device_;
 149   scoped_ptr<OverlayCandidateValidator> overlay_candidate_validator_;
 150   gfx::Size surface_size_;
 151   float device_scale_factor_;
 152
 153   void CommitVSyncParameters(base::TimeTicks timebase,
 154                              base::TimeDelta interval);
 155
 156   void SetNeedsRedrawRect(const gfx::Rect& damage_rect);
 157   void ReclaimResources(const CompositorFrameAck* ack);
 158   void DidLoseOutputSurface();
 159   void SetExternalStencilTest(bool enabled);
 160   void SetExternalDrawConstraints(
 161       const gfx::Transform& transform,
 162       const gfx::Rect& viewport,
 163       const gfx::Rect& clip,
 164       const gfx::Rect& viewport_rect_for_tile_priority,
 165       const gfx::Transform& transform_for_tile_priority,
 166       bool resourceless_software_draw);
 167
 168  private:
 169   void SetUpContext3d();
 170   void ResetContext3d();
 171   void SetMemoryPolicy(const ManagedMemoryPolicy& policy);
 172
 173   bool external_stencil_test_enabled_;
 174
 175   base::WeakPtrFactory<OutputSurface> weak_ptr_factory_;
 176
 177   DISALLOW_COPY_AND_ASSIGN(OutputSurface);
 178 };
 179
 180 }  // namespace cc
 181
 182 #endif  // CC_OUTPUT_OUTPUT_SURFACE_H_