Changeset 41692 in webkit

Timestamp:

Mar 13, 2009 3:47:20 PM (15 years ago)

Author:

eric@webkit.org

Message:

2009-03-13 Stephen White <​senorblanco@chromium.org>

Reviewed by Eric Seidel.

​https://bugs.webkit.org/show_bug.cgi?id=24584

Fix transparent text rendering on Chromium. FontChromiumWin
was calling beginTransparencyLayer()/endTransparencyLayer(), with
a TransparencyWin inside to do GDI ClearType rendering over an
opaque background. TransparencyWin does its special sauce
in the destructor, but it was being called too late to be used
correctly in the layer. Put the special sauce into a new function,
composite(), and call that explicitly instead.

• platform/graphics/chromium/FontChromiumWin.cpp: (WebCore::TransparencyAwareFontPainter::TransparencyAwareFontPainter::~TransparencyAwareFontPainter):
• platform/graphics/chromium/TransparencyWin.cpp: (WebCore::TransparencyWin::~TransparencyWin): (WebCore::TransparencyWin::composite): (WebCore::TransparencyWin::init):
• platform/graphics/chromium/TransparencyWin.h:
• rendering/RenderThemeChromiumWin.cpp: (WebCore::):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/chromium/FontChromiumWin.cpp (modified) (1 diff)
• platform/graphics/chromium/TransparencyWin.cpp (modified) (2 diffs)
• platform/graphics/chromium/TransparencyWin.h (modified) (1 diff)
• rendering/RenderThemeChromiumWin.cpp (modified) (1 diff)

trunk/WebCore/ChangeLog

@@ +1 @@
+2009-03-13  Stephen White  <senorblanco@chromium.org>
+
+        Reviewed by Eric Seidel.
+
+        https://bugs.webkit.org/show_bug.cgi?id=24584
+
+        Fix transparent text rendering on Chromium.  FontChromiumWin
+        was calling beginTransparencyLayer()/endTransparencyLayer(), with
+        a TransparencyWin inside to do GDI ClearType rendering over an
+        opaque background.  TransparencyWin does its special sauce
+        in the destructor, but it was being called too late to be used
+        correctly in the layer.  Put the special sauce into a new function,
+        composite(), and call that explicitly instead.
+
+        * platform/graphics/chromium/FontChromiumWin.cpp:
+        (WebCore::TransparencyAwareFontPainter::TransparencyAwareFontPainter::~TransparencyAwareFontPainter):
+        * platform/graphics/chromium/TransparencyWin.cpp:
+        (WebCore::TransparencyWin::~TransparencyWin):
+        (WebCore::TransparencyWin::composite):
+        (WebCore::TransparencyWin::init):
+        * platform/graphics/chromium/TransparencyWin.h:
+        * rendering/RenderThemeChromiumWin.cpp:
+        (WebCore::):
+
 2009-03-13  Mike Belshe  <mike@belshe.com>
 

trunk/WebCore/platform/graphics/chromium/FontChromiumWin.cpp

@@ -187 +187 @@
     if (!m_useGDI)
         return;  // Nothing to do.
+    m_transparency.composite();
     if (m_createdTransparencyLayer)
         m_graphicsContext->endTransparencyLayer();

trunk/WebCore/platform/graphics/chromium/TransparencyWin.cpp

@@ -158 +158 @@
 TransparencyWin::~TransparencyWin()
 {
+    // This should be false, since calling composite() is mandatory.
+    ASSERT(!m_savedOnDrawContext);
+}
+
+void TransparencyWin::composite()
+{
     // Matches the save() in initializeNewTextContext (or the constructor for
     // SCALE) to put the context back into the same state we found it.
-    if (m_savedOnDrawContext)
+    if (m_savedOnDrawContext) {
         m_drawContext->restore();
+        m_savedOnDrawContext = false;
+    }
 
     switch (m_layerMode) {
@@ -179 +187 @@
                            LayerMode layerMode,
                            TransformMode transformMode,
-                           const IntRect& region) {
+                           const IntRect& region)
+{
     m_destContext = dest;
     m_orgTransform = dest->getCTM();

trunk/WebCore/platform/graphics/chromium/TransparencyWin.h

@@ -135 +135 @@
               const IntRect& region);
 
+    // Combines the source and destination bitmaps using the given mode.
+    void composite();
+
     // Returns the context for drawing into, which may be the destination
     // context, or a temporary one.

trunk/WebCore/rendering/RenderThemeChromiumWin.cpp

@@ -71 +71 @@
     }
 
+    ~ThemePainter()
+    {
+        composite();
+    }
+
 private:
     static LayerMode getLayerMode(GraphicsContext* context, TransformMode transformMode)