third_party/blink/renderer/core/frame/frame_overlay.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. AND ITS CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GOOGLE INC.
 * OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_FRAME_OVERLAY_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_FRAME_OVERLAY_H_

#include <memory>
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/platform/graphics/graphics_layer.h"
#include "third_party/blink/renderer/platform/graphics/graphics_layer_client.h"
#include "third_party/blink/renderer/platform/graphics/paint/display_item_client.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

namespace blink {

class GraphicsContext;
class LocalFrame;

// Manages a layer that is overlaid on a WebLocalFrame's content.
class CORE_EXPORT FrameOverlay : public GraphicsLayerClient,
                                 public DisplayItemClient {
 public:
  class Delegate {
   public:
    virtual ~Delegate() = default;

    // Paints page overlay contents.
    virtual void PaintFrameOverlay(const FrameOverlay&,
                                   GraphicsContext&,
                                   const IntSize& view_size) const = 0;
    // For CompositeAfterPaint. Invalidates composited layers managed by the
    // delegate if any.
    virtual void Invalidate() {}
  };

  static std::unique_ptr<FrameOverlay> Create(
      LocalFrame*,
      std::unique_ptr<FrameOverlay::Delegate>);

  ~FrameOverlay() override;

  void Update();

  // For CompositeAfterPaint.
  void Paint(GraphicsContext&);

  GraphicsLayer* GetGraphicsLayer() const {
    DCHECK(!RuntimeEnabledFeatures::CompositeAfterPaintEnabled());
    return layer_.get();
  }

  // FrameOverlay is always the same size as the viewport.
  IntSize Size() const;

  // DisplayItemClient methods.
  String DebugName() const final { return "FrameOverlay"; }
  LayoutRect VisualRect() const override;

  // GraphicsLayerClient implementation. Not needed for CompositeAfterPaint.
  bool NeedsRepaint(const GraphicsLayer&) const override { return true; }
  IntRect ComputeInterestRect(const GraphicsLayer*,
                              const IntRect&) const override;
  void PaintContents(const GraphicsLayer*,
                     GraphicsContext&,
                     GraphicsLayerPaintingPhase,
                     const IntRect& interest_rect) const override;
  String DebugName(const GraphicsLayer*) const override;

 private:
  FrameOverlay(LocalFrame*, std::unique_ptr<FrameOverlay::Delegate>);

  Persistent<LocalFrame> frame_;
  std::unique_ptr<FrameOverlay::Delegate> delegate_;
  std::unique_ptr<GraphicsLayer> layer_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_PAGE_OVERLAY_H_