src/content/renderer/gpu/compositor_software_output_device.h

   1 // Copyright (c) 2013 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 CONTENT_RENDERER_GPU_COMPOSITOR_SOFTWARE_OUTPUT_DEVICE_H_
   6 #define CONTENT_RENDERER_GPU_COMPOSITOR_SOFTWARE_OUTPUT_DEVICE_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/memory/scoped_vector.h"
  10 #include "base/memory/shared_memory.h"
  11 #include "base/threading/non_thread_safe.h"
  12 #include "cc/output/software_output_device.h"
  13 #include "cc/resources/shared_bitmap.h"
  14 #include "content/public/renderer/render_thread.h"
  15 #include "third_party/skia/include/core/SkBitmap.h"
  16
  17 class SkRegion;
  18
  19 namespace cc {
  20 class SharedBitmapManager;
  21 }
  22
  23 namespace content {
  24
  25 // This class can be created only on the main thread, but then becomes pinned
  26 // to a fixed thread when BindToClient is called.
  27 class CompositorSoftwareOutputDevice
  28     : NON_EXPORTED_BASE(public cc::SoftwareOutputDevice),
  29       NON_EXPORTED_BASE(public base::NonThreadSafe) {
  30  public:
  31   CompositorSoftwareOutputDevice();
  32   ~CompositorSoftwareOutputDevice() override;
  33
  34   void Resize(const gfx::Size& pixel_size, float scale_factor) override;
  35
  36   SkCanvas* BeginPaint(const gfx::Rect& damage_rect) override;
  37   void EndPaint(cc::SoftwareFrameData* frame_data) override;
  38   void EnsureBackbuffer() override;
  39   void DiscardBackbuffer() override;
  40
  41   void ReclaimSoftwareFrame(unsigned id) override;
  42
  43  private:
  44   // Internal buffer class that manages shared memory lifetime and ownership.
  45   // It also tracks buffers' history so we can calculate what's the minimum
  46   // damage rect difference between any two given buffers (see SetParent and
  47   // FindDamageDifferenceFrom).
  48   class Buffer {
  49    public:
  50     explicit Buffer(unsigned id, scoped_ptr<cc::SharedBitmap> bitmap);
  51     ~Buffer();
  52
  53     unsigned id() const { return id_; }
  54
  55     void* memory() const { return shared_bitmap_->pixels(); }
  56     cc::SharedBitmapId shared_bitmap_id() const { return shared_bitmap_->id(); }
  57
  58     bool free() const { return free_; }
  59     void SetFree(bool free) { free_ = free; }
  60
  61     Buffer* parent() const { return parent_; }
  62     void SetParent(Buffer* parent, const gfx::Rect& damage);
  63
  64     bool FindDamageDifferenceFrom(Buffer* buffer, SkRegion* result) const;
  65
  66    private:
  67     const unsigned id_;
  68     scoped_ptr<cc::SharedBitmap> shared_bitmap_;
  69     bool free_;
  70     Buffer* parent_;
  71     gfx::Rect damage_;
  72
  73     DISALLOW_COPY_AND_ASSIGN(Buffer);
  74   };
  75
  76   class CompareById {
  77    public:
  78     CompareById(unsigned id) : id_(id) {}
  79
  80     bool operator()(const Buffer* buffer) const {
  81       return buffer->id() == id_;
  82     }
  83
  84    private:
  85     const unsigned id_;
  86   };
  87
  88   unsigned GetNextId();
  89   Buffer* CreateBuffer();
  90   size_t FindFreeBuffer(size_t hint);
  91
  92   size_t current_index_;
  93   unsigned next_buffer_id_;
  94   ScopedVector<Buffer> buffers_;
  95   ScopedVector<Buffer> awaiting_ack_;
  96   cc::SharedBitmapManager* shared_bitmap_manager_;
  97 };
  98
  99 }  // namespace content
 100
 101 #endif  // CONTENT_RENDERER_GPU_COMPOSITOR_SOFTWARE_OUTPUT_DEVICE_H_