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

webkit/port/platform/graphics/ThemeHelperWin.cpp

+/*
+ * 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. 
+ */
+
+#include "config.h"
+#include "FloatRect.h"
+#include "GraphicsContext.h"
+#include "ThemeHelperWin.h"
+
+namespace WebCore {
+
+static void IntRectToRECT(const IntRect& ir, RECT* r)

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

I guess we can't use operator RECT() because it's in PLATFORM(WIN) ?

+{
+    r->left = ir.x();
+    r->top = ir.y();
+    r->right = ir.right();
+    r->bottom = ir.bottom();
+}
+
+ThemeHelperWin::ThemeHelperWin(GraphicsContext* context,
+                               const IntRect& rect)
+    : m_orgContext(context)
+    , m_orgMatrix(context->getCTM())
+    , m_orgRect(rect)
+{
+    if (m_orgMatrix.b() != 0 ||  // Y skew
+        m_orgMatrix.c() != 0) {  // X skew
+        // Complicated effects, make a copy and draw the bitmap there.
+        m_type = COPY;
+        m_rect.left = 0;
+        m_rect.top = 0;
+        m_rect.right = rect.width();
+        m_rect.bottom = rect.height();
+
+        m_newBuffer.set(ImageBuffer::create(rect.size(), false).release());
+
+        // Theme drawing messes with the transparency.
+        // TODO(brettw) Ideally, we would leave this transparent, but I was
+        // having problems with button drawing, so we fill with white. Buttons
+        // looked good with transparent here and no fixing up of the alpha
+        // later, but text areas didn't. This makes text areas look good but
+        // gives buttons a white halo. Is there a way to fix this? I think
+        // buttons actually have antialised edges which is just not possible
+        // to handle on a transparent background given that it messes with the
+        // alpha channel.
+        FloatRect newContextRect(0, 0, rect.width(), rect.height());
+        GraphicsContext* newContext = m_newBuffer->context();
+        newContext->setFillColor(Color::white);
+        newContext->fillRect(newContextRect);
+
+        return;
+    }
+
+    if (m_orgMatrix.a() != 1.0 ||  // X scale
+        m_orgMatrix.d() != 1.0) {  // Y scale
+        // Only a scaling is applied.
+        m_type = SCALE;
+
+        // Save the transformed coordinates to draw.
+        IntRectToRECT(m_orgMatrix.mapRect(rect), &m_rect);
+        
+        m_orgContext->save();
+        m_orgContext->concatCTM(m_orgContext->getCTM().inverse());
+        return;
+    }
+
+    // Nothing interesting.
+    IntRectToRECT(rect, &m_rect);
+    m_type = ORIGINAL;
+}
+
+ThemeHelperWin::~ThemeHelperWin()
+{
+    switch (m_type) {
+    case SCALE:
+        m_orgContext->restore();
+        break;
+    case COPY: {
+        // Copy the duplicate bitmap with our control to the original canvas.
+        FloatRect destRect(m_orgRect);
+        m_newBuffer->context()->platformContext()->canvas()->
+            getTopPlatformDevice().fixupAlphaBeforeCompositing();
+        m_orgContext->drawImage(m_newBuffer->image(), destRect);
+        break;
+    }
+    case ORIGINAL:
+        break;
+    }
+}
+
+RECT ThemeHelperWin::transformRect(const RECT& r) const
+{
+    IntRect src(r.left, r.top, r.right - r.left, r.bottom - r.top);
+    IntRect dest;
+    switch (m_type) {
+    case SCALE:
+        dest = m_orgMatrix.mapRect(src);
+        break;
+    case COPY:
+        dest = src;
+        dest.move(-m_orgRect.x(), -m_orgRect.y());
+        break;
+    case ORIGINAL:
+        break;
+    }
+
+    RECT output;
+    IntRectToRECT(dest, &output);
+    return output;
+}
+
+}  // namespace WebCore