Add support for arbitrarily transformed Windows buttons text field...

webkit/port/platform/graphics/ThemeHelperWin.h

+/*
+ * Copyright (C) 2008 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 APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 <windows.h>
+
+#include "AffineTransform.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

[M-A Ruel, 2008/11/03 20:18:46]

.

+        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 looke better.

[M-A Ruel, 2008/11/03 20:18:46]

look

+        SCALE,
+
+        // Make a copy of the control and then transform it ourselves after
+        // Windows draws it. This allows us to get complex effects.
+        COPY

[M-A Ruel, 2008/11/03 20:18:46]

,

+    };
+
+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 RECT& rect() { return m_rect; }
+
+    RECT transformRect(const RECT& r) const;
+
+private:
+    Type m_type;
+
+    // The original canvas to wrote to. Not owned by this class.
+    GraphicsContext* m_orgContext;
+    AffineTransform m_orgMatrix;
+    IntRect m_orgRect;
+
+    // When type_ == COPY, this will be a new surface owned by this class that

[M-A Ruel, 2008/11/03 20:18:46]

m_type

+    // represents the copy.
+    OwnPtr<ImageBuffer> m_newBuffer;
+
+    // The control rectangle in the cooredinate space of canvas().
+    RECT m_rect;
+};
+
+}  // namespace WebCore
+
+#endif  // ThemeHelperWin_h