Support subpixel values for text-shadow and box-shadow

Source/core/rendering/InlineTextBox.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 384 matching lines @@
     const FloatPoint& textOrigin, const FloatRect& boxRect,
     const ShadowList* shadowList, bool stroked, bool horizontal)
 {
     // Text shadows are disabled when printing. http://crbug.com/258321
     bool hasShadow = shadowList && !context->printing();
 
     if (hasShadow) {
         DrawLooper drawLooper;
         for (size_t i = shadowList->shadows().size(); i--; ) {
             const ShadowData& shadow = shadowList->shadows()[i];
-            int shadowX = horizontal ? shadow.x() : shadow.y();
-            int shadowY = horizontal ? shadow.y() : -shadow.x();
+            float shadowX = horizontal ? shadow.x() : shadow.y();
+            float shadowY = horizontal ? shadow.y() : -shadow.x();
             FloatSize offset(shadowX, shadowY);
             drawLooper.addShadow(offset, shadow.blur(), renderer->resolveColor(shadow.color()),
                 DrawLooper::ShadowRespectsTransforms, DrawLooper::ShadowIgnoresAlpha);
         }
         drawLooper.addUnmodifiedContent();
         context->setDrawLooper(drawLooper);
     }
 
     TextRunPaintInfo textRunPaintInfo(textRun);
     textRunPaintInfo.bounds = boxRect;
@@ skipping 665 matching lines @@
 
     RenderStyle* styleToUse = renderer()->style(isFirstLineStyle());
     int baseline = styleToUse->fontMetrics().ascent();
 
     size_t shadowCount = shadowList ? shadowList->shadows().size() : 0;
     // Set the thick of the line to be 10% (or something else ?)of the computed font size and not less than 1px.
     // Using computedFontSize should take care of zoom as well.
     const float textDecorationThickness = std::max(1.f, styleToUse->computedFontSize() / 10.f);
     context->setStrokeThickness(textDecorationThickness);
 
-    int extraOffset = 0;
+    float extraOffset = 0;
     if (!linesAreOpaque && shadowCount > 1) {
         FloatRect clipRect(localOrigin, FloatSize(width, baseline + 2));
         for (size_t i = shadowCount; i--; ) {
             const ShadowData& s = shadowList->shadows()[i];
             FloatRect shadowRect(localOrigin, FloatSize(width, baseline + 2));
             shadowRect.inflate(s.blur());
-            int shadowX = isHorizontal() ? s.x() : s.y();
-            int shadowY = isHorizontal() ? s.y() : -s.x();
+            float shadowX = isHorizontal() ? s.x() : s.y();
+            float shadowY = isHorizontal() ? s.y() : -s.x();
             shadowRect.move(shadowX, shadowY);
             clipRect.unite(shadowRect);
-            extraOffset = max(extraOffset, max(0, shadowY) + s.blur());
+            extraOffset = max(extraOffset, max(0.0f, shadowY) + s.blur());
         }
         context->clip(clipRect);
         extraOffset += baseline + 2;
         localOrigin.move(0, extraOffset);
     }
 
     for (size_t i = max(static_cast<size_t>(1), shadowCount); i--; ) {
         // Even if we have no shadows, we still want to run the code below this once.
         if (i < shadowCount) {
             if (!i) {
                 // The last set of lines paints normally inside the clip.
                 localOrigin.move(0, -extraOffset);
                 extraOffset = 0;
             }
             const ShadowData& shadow = shadowList->shadows()[i];
-            int shadowX = isHorizontal() ? shadow.x() : shadow.y();
-            int shadowY = isHorizontal() ? shadow.y() : -shadow.x();
+            float shadowX = isHorizontal() ? shadow.x() : shadow.y();
+            float shadowY = isHorizontal() ? shadow.y() : -shadow.x();
             context->setShadow(FloatSize(shadowX, shadowY - extraOffset), shadow.blur(), shadow.color());
         }
 
         // Offset between lines - always non-zero, so lines never cross each other.
         float doubleOffset = textDecorationThickness + 1.f;
         context->setStrokeStyle(textDecorationStyleToStrokeStyle(decorationStyle));
         if (deco & TextDecorationUnderline) {
             context->setStrokeColor(underline);
             const int underlineOffset = computeUnderlineOffset(styleToUse->textUnderlinePosition(), styleToUse->fontMetrics(), this, textDecorationThickness);
             switch (decorationStyle) {
@@ skipping 426 matching lines @@
     printedCharacters = fprintf(stderr, "\t%s %p", obj->renderName(), obj);
     const int rendererCharacterOffset = 24;
     for (; printedCharacters < rendererCharacterOffset; printedCharacters++)
         fputc(' ', stderr);
     fprintf(stderr, "(%d,%d) \"%s\"\n", start(), start() + len(), value.utf8().data());
 }
 
 #endif
 
 } // namespace WebCore