xref: /external/chromium_org/third_party/WebKit/Source/platform/graphics/GraphicsContextStateSaver.h

// Copyright (C) 2013 Google Inc. All rights reserved.
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#ifndef GraphicsContextStateSaver_h
#define GraphicsContextStateSaver_h

#include "platform/PlatformExport.h"
#include "platform/graphics/GraphicsContext.h"

namespace blink {

class PLATFORM_EXPORT GraphicsContextStateSaver {
    WTF_MAKE_FAST_ALLOCATED;
public:
    GraphicsContextStateSaver(GraphicsContext& context, bool saveAndRestore = true)
        : m_context(context)
        , m_saveAndRestore(saveAndRestore)
    {
        if (m_saveAndRestore)
            m_context.save();
    }

    ~GraphicsContextStateSaver()
    {
        if (m_saveAndRestore)
            m_context.restore();
    }

    void save()
    {
        ASSERT(!m_saveAndRestore);
        m_context.save();
        m_saveAndRestore = true;
    }

    void saveIfNeeded()
    {
        if (saved())
            return;
        save();
    }

    void restore()
    {
        ASSERT(m_saveAndRestore);
        m_context.restore();
        m_saveAndRestore = false;
    }

    GraphicsContext* context() const { return &m_context; }
    bool saved() const { return m_saveAndRestore; }

private:
    GraphicsContext& m_context;
    bool m_saveAndRestore;
};

} // namespace blink

#endif // GraphicsContextStateSaver_h