Underline Thickness is not uniform

Source/core/rendering/InlineTextBox.cpp

Index: Source/core/rendering/InlineTextBox.cpp
diff --git a/Source/core/rendering/InlineTextBox.cpp b/Source/core/rendering/InlineTextBox.cpp
index dcb093c0379302ef922e0d75d88c12ff06442363..766de5c3e6db6002325761dd33b0b80aaf0a0080 100644
--- a/Source/core/rendering/InlineTextBox.cpp
+++ b/Source/core/rendering/InlineTextBox.cpp
@@ -60,6 +60,7 @@ struct SameSizeAsInlineTextBox : public InlineBox {
     unsigned variables[1];
     unsigned short variables2[2];
     void* pointers[2];
+    float u;
 };
 
 COMPILE_ASSERT(sizeof(InlineTextBox) == sizeof(SameSizeAsInlineTextBox), InlineTextBox_should_stay_small);
@@ -464,13 +465,11 @@ bool InlineTextBox::getEmphasisMarkPosition(RenderStyle* style, TextEmphasisPosi
     return !rubyText || !rubyText->firstLineBox();
 }
 
-void InlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit /*lineTop*/, LayoutUnit /*lineBottom*/)
+bool InlineTextBox::isLogicalStartEndCorrect(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     if (isLineBreak() || !paintInfo.shouldPaintWithinRoot(&renderer()) || renderer().style()->visibility() != VISIBLE
         || m_truncation == cFullTruncation || paintInfo.phase == PaintPhaseOutline || !m_len)
-        return;
-
-    ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);
+        return false;
 
     LayoutUnit logicalLeftSide = logicalLeftVisualOverflow();
     LayoutUnit logicalRightSide = logicalRightVisualOverflow();
@@ -480,19 +479,31 @@ void InlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset,
     LayoutUnit paintEnd = isHorizontal() ? paintInfo.rect.maxX() : paintInfo.rect.maxY();
     LayoutUnit paintStart = isHorizontal() ? paintInfo.rect.x() : paintInfo.rect.y();
 
-    LayoutPoint adjustedPaintOffset = roundedIntPoint(paintOffset);
-
     if (logicalStart >= paintEnd || logicalStart + logicalExtent <= paintStart)
-        return;
+        return false;
 
     bool isPrinting = textRenderer().document().printing();
 
     // Determine whether or not we're selected.
     bool haveSelection = !isPrinting && paintInfo.phase != PaintPhaseTextClip && selectionState() != RenderObject::SelectionNone;
-    if (!haveSelection && paintInfo.phase == PaintPhaseSelection)
+    if (!haveSelection && paintInfo.phase == PaintPhaseSelection) {
         // When only painting the selection, don't bother to paint if there is none.
+        return false;
+    }
+
+    return true;
+}
+void InlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit /*lineTop*/, LayoutUnit /*lineBottom*/)
+{
+    ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);
+
+    if (!isLogicalStartEndCorrect(paintInfo, paintOffset))
         return;
 
+    LayoutPoint adjustedPaintOffset = roundedIntPoint(paintOffset);
+    bool isPrinting = textRenderer().document().printing();
+    bool haveSelection = !isPrinting && paintInfo.phase != PaintPhaseTextClip && selectionState() != RenderObject::SelectionNone;
+
     if (m_truncation != cNoTruncation) {
         if (renderer().containingBlock()->style()->isLeftToRightDirection() != isLeftToRightDirection()) {
             // Make the visible fragment of text hug the edge closest to the rest of the run by moving the origin
@@ -750,44 +761,15 @@ void InlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset,
         }
     }
 
-    // Paint decorations
+    // lets only store decorations style and underline thickness, painting of decoration style will be done later
     TextDecoration textDecorations = styleToUse->textDecorationsInEffect();
     if (textDecorations != TextDecorationNone && paintInfo.phase != PaintPhaseSelection) {
-        updateGraphicsContext(context, textFillColor, textStrokeColor, textStrokeWidth);
-        if (combinedText)
-            context->concatCTM(rotation(boxRect, Clockwise));
-        paintDecoration(context, boxOrigin, textDecorations, textShadow);
-        if (combinedText)
-            context->concatCTM(rotation(boxRect, Counterclockwise));
-    }
+        float textDecorationThickness = styleToUse->fontMetrics().underlineThickness();
+        int fontHeightInt = (int)(styleToUse->fontMetrics().floatHeight() + 0.5);
+        if ((textDecorationThickness == 0.f) || (textDecorationThickness >= (fontHeightInt >> 1)))
+            textDecorationThickness = std::max(1.f, styleToUse->computedFontSize() / 10.f);
 
-    if (paintInfo.phase == PaintPhaseForeground) {
-        paintDocumentMarkers(context, boxOrigin, styleToUse, font, false);
-
-        if (useCustomUnderlines) {
-            const Vector<CompositionUnderline>& underlines = renderer().frame()->inputMethodController().customCompositionUnderlines();
-            size_t numUnderlines = underlines.size();
-
-            for (size_t index = 0; index < numUnderlines; ++index) {
-                const CompositionUnderline& underline = underlines[index];
-
-                if (underline.endOffset <= start())
-                    // underline is completely before this run.  This might be an underline that sits
-                    // before the first run we draw, or underlines that were within runs we skipped
-                    // due to truncation.
-                    continue;
-
-                if (underline.startOffset <= end()) {
-                    // underline intersects this run.  Paint it.
-                    paintCompositionUnderline(context, boxOrigin, underline);
-                    if (underline.endOffset > end() + 1)
-                        // underline also runs into the next run. Bail now, no more marker advancement.
-                        break;
-                } else
-                    // underline is completely after this run, bail.  A later run will paint it.
-                    break;
-            }
-        }
+        setDecorationThickness(textDecorationThickness);
     }
 
     if (shouldRotate)
@@ -1093,7 +1075,7 @@ static void paintAppliedDecoration(GraphicsContext* context, FloatPoint start, f
     }
 }
 
-void InlineTextBox::paintDecoration(GraphicsContext* context, const FloatPoint& boxOrigin, TextDecoration deco, const ShadowList* shadowList)
+void InlineTextBox::paintDecoration(GraphicsContext* context, const FloatPoint& boxOrigin, TextDecoration deco, const ShadowList* shadowList, float decorationThickness)
 {
     GraphicsContextStateSaver stateSaver(*context);
 
@@ -1129,10 +1111,15 @@ void InlineTextBox::paintDecoration(GraphicsContext* context, const FloatPoint&
     // Using computedFontSize should take care of zoom as well.
 
     // Update Underline thickness, in case we have Faulty Font Metrics calculating underline thickness by old method.
-    float textDecorationThickness = styleToUse->fontMetrics().underlineThickness();
-    int fontHeightInt  = (int)(styleToUse->fontMetrics().floatHeight() + 0.5);
-    if ((textDecorationThickness == 0.f) || (textDecorationThickness >= (fontHeightInt >> 1)))
-        textDecorationThickness = std::max(1.f, styleToUse->computedFontSize() / 10.f);
+    float textDecorationThickness = 0;
+    if (!decorationThickness) {
+        textDecorationThickness = styleToUse->fontMetrics().underlineThickness();
+        int fontHeightInt = (int)(styleToUse->fontMetrics().floatHeight() + 0.5);
+        if ((textDecorationThickness == 0.f) || (textDecorationThickness >= (fontHeightInt >> 1)))
+            textDecorationThickness = std::max(1.f, styleToUse->computedFontSize() / 10.f);
+    } else {
+        textDecorationThickness = decorationThickness;
+    }
 
     context->setStrokeThickness(textDecorationThickness);
 
@@ -1188,6 +1175,72 @@ void InlineTextBox::paintDecoration(GraphicsContext* context, const FloatPoint&
     }
 }
 
+void InlineTextBox::paintDecorationStyle(PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit lineTop, LayoutUnit lineBottom, float decorationThickness)
+{
+    ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);
+
+    if (!isLogicalStartEndCorrect(paintInfo, paintOffset))
+        return;
+
+    LayoutPoint adjustedPaintOffset = roundedIntPoint(paintOffset);
+    GraphicsContext* context = paintInfo.context;
+    RenderObject& rendererToUse = renderer();
+    RenderStyle* styleToUse = rendererToUse.style(isFirstLineStyle());
+
+    FloatPoint boxOrigin = locationIncludingFlipping();
+    boxOrigin.move(adjustedPaintOffset.x().toFloat(), adjustedPaintOffset.y().toFloat());
+
+    TextDecoration deco = styleToUse->textDecorationsInEffect();
+    const ShadowList* textShadow = (context->printing() || paintInfo.forceBlackText()) ? 0 : styleToUse->textShadow();
+
+    paintDecoration(context, boxOrigin, deco, textShadow, decorationThickness);
+    if (paintInfo.phase == PaintPhaseForeground) {
+        const Font& font = styleToUse->font();
+        bool containsComposition = renderer().node() && renderer().frame()->inputMethodController().compositionNode() == renderer().node();
+        bool useCustomUnderlines = containsComposition && renderer().frame()->inputMethodController().compositionUsesCustomUnderlines();
+
+        paintDocumentMarkers(context, boxOrigin, styleToUse, font, false);
+
+        if (useCustomUnderlines) {
+            const Vector<CompositionUnderline>& underlines = renderer().frame()->inputMethodController().customCompositionUnderlines();
+            size_t numUnderlines = underlines.size();
+
+            for (size_t index = 0; index < numUnderlines; ++index) {
+                const CompositionUnderline& underline = underlines[index];
+
+                if (underline.endOffset <= start()) {
+                    // underline is completely before this run. This might be an underline that sits
+                    // before the first run we draw, or underlines that were within runs we skipped
+                    // due to truncation.
+                    continue;
+                }
+
+                if (underline.startOffset <= end()) {
+                    // underline intersects this run. Paint it.
+                    paintCompositionUnderline(context, boxOrigin, underline);
+                    if (underline.endOffset > end() + 1) {
+                        // underline also runs into the next run. Bail now, no more marker advancement.
+                        break;
+                    }
+                } else {
+                    // underline is completely after this run, bail. A later run will paint it.
+                    break;
+                }
+            }
+        }
+    }
+}
+
+void InlineTextBox::getPaintDecorationSyle(PaintInfo& paintInfo, const LayoutPoint& paintOffset, float * decorationThickness)
+{
+    *decorationThickness = 0;
+    if (isLineBreak() || !paintInfo.shouldPaintWithinRoot(&renderer()) || renderer().style()->visibility() != VISIBLE
+        || m_truncation == cFullTruncation || paintInfo.phase == PaintPhaseOutline || !m_len)
+        return;
+
+    *decorationThickness = getDecorationThickness();
+}
+
 static GraphicsContext::DocumentMarkerLineStyle lineStyleForMarkerType(DocumentMarker::MarkerType markerType)
 {
     switch (markerType) {