cc/output/overlay_candidate.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_OUTPUT_OVERLAY_CANDIDATE_H_
#define CC_OUTPUT_OVERLAY_CANDIDATE_H_

#include <vector>

#include "cc/base/cc_export.h"
#include "cc/quads/render_pass.h"
#include "cc/resources/resource_format.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/rect_f.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/overlay_transform.h"
#include "ui/gfx/transform.h"

namespace gfx {
class Rect;
}

namespace cc {

class DrawQuad;
class IOSurfaceDrawQuad;
class StreamVideoDrawQuad;
class TextureDrawQuad;
class ResourceProvider;

class CC_EXPORT OverlayCandidate {
 public:
  // Returns true and fills in |candidate| if |draw_quad| is of a known quad
  // type and contains an overlayable resource.
  static bool FromDrawQuad(ResourceProvider* resource_provider,
                           const DrawQuad* quad,
                           OverlayCandidate* candidate);
  // Returns true if |quad| will not block quads underneath from becoming
  // an overlay.
  static bool IsInvisibleQuad(const DrawQuad* quad);

  // Returns true if any any of the quads in the list given by |quad_list_begin|
  // and |quad_list_end| are visible and on top of |candidate|.
  static bool IsOccluded(const OverlayCandidate& candidate,
                         QuadList::ConstIterator quad_list_begin,
                         QuadList::ConstIterator quad_list_end);

  OverlayCandidate();
  ~OverlayCandidate();

  // Transformation to apply to layer during composition.
  gfx::OverlayTransform transform;
  // Format of the buffer to composite.
  ResourceFormat format;
  // Size of the resource, in pixels.
  gfx::Size resource_size_in_pixels;
  // Rect on the display to position the overlay to. Implementer must convert
  // to integer coordinates if setting |overlay_handled| to true.
  gfx::RectF display_rect;
  // Crop within the buffer to be placed inside |display_rect|.
  gfx::RectF uv_rect;
  // Quad geometry rect after applying the quad_transform().
  gfx::Rect quad_rect_in_target_space;
  // Clip rect in the target content space after composition.
  gfx::Rect clip_rect;
  // If the quad is clipped after composition.
  bool is_clipped;
  // True if the texture for this overlay should be the same one used by the
  // output surface's main overlay.
  bool use_output_surface_for_resource;
  // Texture resource to present in an overlay.
  unsigned resource_id;
  // Stacking order of the overlay plane relative to the main surface,
  // which is 0. Signed to allow for "underlays".
  int plane_z_order;
  // True if the overlay does not have any visible quads on top of it. Set by
  // the strategy so the OverlayProcessor can consider subtracting damage caused
  // by underlay quads.
  bool is_unoccluded;

  // To be modified by the implementer if this candidate can go into
  // an overlay.
  bool overlay_handled;

 private:
  static bool FromTextureQuad(ResourceProvider* resource_provider,
                              const TextureDrawQuad* quad,
                              OverlayCandidate* candidate);
  static bool FromStreamVideoQuad(ResourceProvider* resource_provider,
                                  const StreamVideoDrawQuad* quad,
                                  OverlayCandidate* candidate);
  static bool FromIOSurfaceQuad(ResourceProvider* resource_provider,
                                const IOSurfaceDrawQuad* quad,
                                OverlayCandidate* candidate);
};

typedef std::vector<OverlayCandidate> OverlayCandidateList;

}  // namespace cc

#endif  // CC_OUTPUT_OVERLAY_CANDIDATE_H_