third_party/WebKit/Source/modules/imagebitmap/ImageBitmapRenderingContext.h

// Copyright 2016 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 ImageBitmapRenderingContext_h
#define ImageBitmapRenderingContext_h

#include "core/html/canvas/CanvasRenderingContext.h"
#include "core/html/canvas/CanvasRenderingContextFactory.h"
#include "modules/ModulesExport.h"
#include "wtf/RefPtr.h"

namespace blink {

class ImageBitmap;

class MODULES_EXPORT ImageBitmapRenderingContext final : public CanvasRenderingContext {
    DEFINE_WRAPPERTYPEINFO();
public:
    class Factory : public CanvasRenderingContextFactory {
        WTF_MAKE_NONCOPYABLE(Factory);
    public:
        Factory() {}
        ~Factory() override {}

        CanvasRenderingContext* create(HTMLCanvasElement*, const CanvasContextCreationAttributes&, Document&) override;
        CanvasRenderingContext::ContextType getContextType() const override { return CanvasRenderingContext::ContextImageBitmap; }
    };

    // Script API
    void transferFromImageBitmap(ImageBitmap*);

    // CanvasRenderingContext implementation
    ContextType getContextType() const override { return CanvasRenderingContext::ContextImageBitmap; }
    void setIsHidden(bool) override { }
    bool isContextLost() const override { return false; }
    bool paint(GraphicsContext&, const IntRect&) override;
    void setCanvasGetContextResult(RenderingContext&) final;
    PassRefPtr<Image> getImage(SnapshotReason) const final { return m_image.get(); }

    // TODO(junov): Implement GPU accelerated rendering using a layer bridge
    WebLayer* platformLayer() const override { return nullptr; }
    // TODO(junov): handle lost contexts when content is GPU-backed
    void loseContext(LostContextMode) override { }

    void stop() override;

    bool isPaintable() const final { return m_image.get(); }

    virtual ~ImageBitmapRenderingContext();

private:
    ImageBitmapRenderingContext(HTMLCanvasElement*, const CanvasContextCreationAttributes&, Document&);

    RefPtr<Image> m_image;
};

DEFINE_TYPE_CASTS(ImageBitmapRenderingContext, CanvasRenderingContext, context,
    context->getContextType() == CanvasRenderingContext::ContextImageBitmap,
    context.getContextType() == CanvasRenderingContext::ContextImageBitmap);

} // blink

#endif