cc/layers/surface_layer.h

// Copyright 2014 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 CC_LAYERS_SURFACE_LAYER_H_
#define CC_LAYERS_SURFACE_LAYER_H_

#include "cc/base/cc_export.h"
#include "cc/layers/layer.h"
#include "cc/surfaces/surface_id.h"
#include "cc/surfaces/surface_sequence.h"
#include "ui/gfx/size.h"

namespace cc {

// A layer that renders a surface referencing the output of another compositor
// instance or client.
class CC_EXPORT SurfaceLayer : public Layer {
 public:
  // This callback is run when a SurfaceSequence needs to be satisfied, but
  // the parent compositor is unable to. It can be called on either the main
  // or impl threads.
  using SatisfyCallback = base::Callback<void(SurfaceSequence)>;

  // This callback is run to require that a specific SurfaceSequence is
  // received before a SurfaceId is destroyed.
  using RequireCallback = base::Callback<void(SurfaceId, SurfaceSequence)>;

  static scoped_refptr<SurfaceLayer> Create(
      const SatisfyCallback& satisfy_callback,
      const RequireCallback& require_callback);

  void SetSurfaceId(SurfaceId surface_id, float scale, const gfx::Size& size);

  // Layer overrides.
  scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl) override;
  void SetLayerTreeHost(LayerTreeHost* host) override;
  void PushPropertiesTo(LayerImpl* layer) override;
  void CalculateContentsScale(float ideal_contents_scale,
                              float* contents_scale_x,
                              float* contents_scale_y,
                              gfx::Size* content_bounds) override;

 protected:
  SurfaceLayer(const SatisfyCallback& satisfy_callback,
               const RequireCallback& require_callback);
  bool HasDrawableContent() const override;

 private:
  ~SurfaceLayer() override;
  void CreateNewDestroySequence();
  void SatisfyDestroySequence();

  SurfaceId surface_id_;
  gfx::Size surface_size_;
  float surface_scale_;
  SurfaceSequence destroy_sequence_;
  SatisfyCallback satisfy_callback_;
  RequireCallback require_callback_;

  DISALLOW_COPY_AND_ASSIGN(SurfaceLayer);
};

}  // namespace cc

#endif  // CC_LAYERS_SURFACE_LAYER_H_