third_party/WebKit/Source/core/paint/SVGFilterPainter.h

// Copyright 2015 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 SVGFilterPainter_h
#define SVGFilterPainter_h

#include "platform/graphics/GraphicsContext.h"
#include "platform/graphics/paint/PaintController.h"
#include "wtf/Allocator.h"
#include <memory>

namespace blink {

class FilterData;
class LayoutObject;
class LayoutSVGResourceFilter;

class SVGFilterRecordingContext {
    USING_FAST_MALLOC(SVGFilterRecordingContext);
    WTF_MAKE_NONCOPYABLE(SVGFilterRecordingContext);
public:
    explicit SVGFilterRecordingContext(GraphicsContext& initialContext) : m_initialContext(initialContext) { }

    GraphicsContext* beginContent(FilterData*);
    void endContent(FilterData*);

    GraphicsContext& paintingContext() const { return m_initialContext; }

private:
    std::unique_ptr<PaintController> m_paintController;
    std::unique_ptr<GraphicsContext> m_context;
    GraphicsContext& m_initialContext;
};

class SVGFilterPainter {
    STACK_ALLOCATED();
public:
    SVGFilterPainter(LayoutSVGResourceFilter& filter) : m_filter(filter) { }

    // Returns the context that should be used to paint the filter contents, or
    // null if the content should not be recorded.
    GraphicsContext* prepareEffect(const LayoutObject&, SVGFilterRecordingContext&);
    void finishEffect(const LayoutObject&, SVGFilterRecordingContext&);

private:
    LayoutSVGResourceFilter& m_filter;
};

} // namespace blink

#endif // SVGFilterPainter_h