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third_party/WebKit/WebCore/platform/graphics/chromium/ThemeHelperChromiumWin.h

-/*
- * Copyright (c) 2008, 2009, 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:
- * 
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * 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.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- * 
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
- * OWNER OR 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 ThemeHelperWin_h
-#define ThemeHelperWin_h
-
-#include "TransformationMatrix.h"
-#include "ImageBuffer.h"
-#include "IntRect.h"
-#include <wtf/OwnPtr.h>
-
-namespace WebCore {
-
-class GraphicsContext;
-class IntRect;
-
-// Helps drawing theme elements like buttons and scroll bars. This will handle
-// translations and scalings that Windows might not, by either making Windows
-// draw the appropriate sized control, or by rendering it into an off-screen
-// context and transforming it ourselves.
-class ThemeHelperWin {
-    enum Type {
-        // Use the original canvas with no changes. This is the normal mode.
-        ORIGINAL,
-
-        // Use the original canvas but scale the rectangle of the control so
-        // that it will be the correct size, undoing any scale already on the
-        // canvas. This will have the effect of just drawing the control bigger
-        // or smaller and not actually expanding or contracting the pixels in
-        // it. This usually looks better.
-        SCALE,
-
-        // Make a copy of the control and then transform it ourselves after
-        // Windows draws it. This allows us to get complex effects.
-        COPY,
-    };
-
-public:
-    // Prepares drawing a control with the given rect to the given context.
-    ThemeHelperWin(GraphicsContext* context, const IntRect& rect);
-    ~ThemeHelperWin();
-
-    // Returns the context to draw the control into, which may be the original
-    // or the copy, depending on the mode.
-    GraphicsContext* context()
-    {
-        return m_newBuffer.get() ? m_newBuffer->context() : m_orgContext;
-    }
-
-    // Returns the rectangle in which to draw into the canvas() by Windows.
-    const IntRect& rect() { return m_rect; }
-
-private:
-    Type m_type;
-
-    // The original canvas to wrote to. Not owned by this class.
-    GraphicsContext* m_orgContext;
-    TransformationMatrix m_orgMatrix;
-    IntRect m_orgRect;
-
-    // When m_type == COPY, this will be a new surface owned by this class that
-    // represents the copy.
-    OwnPtr<ImageBuffer> m_newBuffer;
-
-    // The control rectangle in the coordinate space of canvas().
-    IntRect m_rect;
-};
-
-}  // namespace WebCore
-
-#endif  // ThemeHelperWin_h