Add support for multiple text decorations with same line positioning

Source/core/paint/InlineTextBoxPainter.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/paint/InlineTextBoxPainter.h"
 
 #include "core/editing/CompositionUnderline.h"
 #include "core/editing/Editor.h"
 #include "core/editing/markers/DocumentMarkerController.h"
 #include "core/editing/markers/RenderedDocumentMarker.h"
 #include "core/frame/LocalFrame.h"
 #include "core/layout/LayoutBlock.h"
 #include "core/layout/LayoutTextCombine.h"
 #include "core/layout/LayoutTheme.h"
 #include "core/layout/line/InlineTextBox.h"
 #include "core/paint/BoxPainter.h"
 #include "core/paint/LayoutObjectDrawingRecorder.h"
 #include "core/paint/PaintInfo.h"
 #include "core/paint/TextPainter.h"
+#include "core/style/AppliedTextDecoration.h"
 #include "platform/graphics/GraphicsContextStateSaver.h"
 #include "wtf/Optional.h"
 
 namespace blink {
 
 typedef WTF::HashMap<const InlineTextBox*, TextBlobPtr> InlineTextBoxBlobCacheMap;
 static InlineTextBoxBlobCacheMap* gTextBlobCache;
 
 static const int misspellingLineThickness = 3;
 
@@ skipping 507 matching lines @@
 
     ASSERT_NOT_REACHED();
     return fontMetrics.ascent() + gap;
 }
 
 static bool shouldSetDecorationAntialias(TextDecorationStyle decorationStyle)
 {
     return decorationStyle == TextDecorationStyleDotted || decorationStyle == TextDecorationStyleDashed;
 }
 
-static bool shouldSetDecorationAntialias(TextDecorationStyle underline, TextDecorationStyle overline, TextDecorationStyle linethrough)
-{
-    return shouldSetDecorationAntialias(underline) || shouldSetDecorationAntialias(overline) || shouldSetDecorationAntialias(linethrough);
-}
-
 static StrokeStyle textDecorationStyleToStrokeStyle(TextDecorationStyle decorationStyle)
 {
     StrokeStyle strokeStyle = SolidStroke;
     switch (decorationStyle) {
     case TextDecorationStyleSolid:
         strokeStyle = SolidStroke;
         break;
     case TextDecorationStyleDouble:
         strokeStyle = DoubleStroke;
         break;
@@ skipping 127 matching lines @@
             x += 2 * step;
             path.addBezierCurveTo(controlPoint1, controlPoint2, FloatPoint(x, yAxis));
         }
     }
 
     context->setShouldAntialias(true);
     context->strokePath(path);
 }
 
 static void paintAppliedDecoration(GraphicsContext* context, FloatPoint start, float width, float doubleOffset, int wavyOffsetFactor,
-    LayoutObject::AppliedTextDecoration decoration, float thickness, bool antialiasDecoration, bool isPrinting)
+    AppliedTextDecoration decoration, float thickness, bool antialiasDecoration, bool isPrinting)
 {
-    context->setStrokeStyle(textDecorationStyleToStrokeStyle(decoration.style));
-    context->setStrokeColor(decoration.color);
+    context->setStrokeStyle(textDecorationStyleToStrokeStyle(decoration.style()));
+    context->setStrokeColor(decoration.color());
 
-    switch (decoration.style) {
+    switch (decoration.style()) {
     case TextDecorationStyleWavy:
         strokeWavyTextDecoration(context, start + FloatPoint(0, doubleOffset * wavyOffsetFactor), start + FloatPoint(width, doubleOffset * wavyOffsetFactor), thickness);
         break;
     case TextDecorationStyleDotted:
     case TextDecorationStyleDashed:
         context->setShouldAntialias(antialiasDecoration);
         // Fall through
     default:
         context->drawLineForText(FloatPoint(start), width, isPrinting);
 
-        if (decoration.style == TextDecorationStyleDouble)
+        if (decoration.style() == TextDecorationStyleDouble)
             context->drawLineForText(start + FloatPoint(0, doubleOffset), width, isPrinting);
     }
 }
 
 void InlineTextBoxPainter::paintDecoration(const PaintInfo& paintInfo, const LayoutPoint& boxOrigin, TextDecoration deco)

[Timothy Loh, 2015/09/22 05:00:23]

Does this patch remove our usage of TextDecoration as an enum bitset?

[sashab, 2015/09/24 01:19:27]

No, SVGInlineTextBoxPainter and InlineTextBoxPainter still check
decoration.lines() & TextDecorationUnderline etc to see if the line is included
in the decoration. Maybe I don't understand your question. Are you asking me to
remove all callsites that use bit operations to check the applied decoration
lines? Maybe use decoration.hasUnderline() etc instead?

[Timothy Loh, 2015/09/24 01:38:15]

Are the TextDecoration argument here and the textDecorationsInEffect methods no
longer needed?

 {
     if (m_inlineTextBox.truncation() == cFullTruncation)
         return;
 
     GraphicsContext* context = paintInfo.context;
     GraphicsContextStateSaver stateSaver(*context);
 
     LayoutPoint localOrigin(boxOrigin);
 
     LayoutUnit width = m_inlineTextBox.logicalWidth();
     if (m_inlineTextBox.truncation() != cNoTruncation) {
         width = m_inlineTextBox.layoutObject().width(m_inlineTextBox.start(), m_inlineTextBox.truncation(), m_inlineTextBox.textPos(), m_inlineTextBox.isLeftToRightDirection() ? LTR : RTL, m_inlineTextBox.isFirstLineStyle());
         if (!m_inlineTextBox.isLeftToRightDirection())
             localOrigin.move(m_inlineTextBox.logicalWidth() - width, 0);
     }
 
-    // Get the text decoration colors.
-    LayoutObject::AppliedTextDecoration underline, overline, linethrough;
-    m_inlineTextBox.layoutObject().getTextDecorations(deco, underline, overline, linethrough, true);
-    if (m_inlineTextBox.isFirstLineStyle())
-        m_inlineTextBox.layoutObject().getTextDecorations(deco, underline, overline, linethrough, true, true);
+    const Vector<AppliedTextDecoration>& decorations = m_inlineTextBox.layoutObject().style(m_inlineTextBox.isFirstLineStyle())->appliedTextDecorations();
 
     // Use a special function for underlines to get the positioning exactly right.
     bool isPrinting = paintInfo.isPrinting();
 
     const ComputedStyle& styleToUse = m_inlineTextBox.layoutObject().styleRef(m_inlineTextBox.isFirstLineStyle());
     float baseline = styleToUse.fontMetrics().ascent();
 
     // 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.
 
     // 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);
 
     context->setStrokeThickness(textDecorationThickness);
 
-    bool antialiasDecoration = shouldSetDecorationAntialias(overline.style, underline.style, linethrough.style);
+    bool antialiasDecoration = false;
+    for (const auto& decoration : decorations)
+        antialiasDecoration |= shouldSetDecorationAntialias(decoration.style());
 
     // Offset between lines - always non-zero, so lines never cross each other.
     float doubleOffset = textDecorationThickness + 1.f;
 
-    if (deco & TextDecorationUnderline) {
-        const int underlineOffset = computeUnderlineOffset(styleToUse.textUnderlinePosition(), styleToUse.fontMetrics(), &m_inlineTextBox, textDecorationThickness);
-        paintAppliedDecoration(context, FloatPoint(localOrigin) + FloatPoint(0, underlineOffset), width.toFloat(), doubleOffset, 1, underline, textDecorationThickness, antialiasDecoration, isPrinting);
-    }
-    if (deco & TextDecorationOverline) {
-        paintAppliedDecoration(context, FloatPoint(localOrigin), width.toFloat(), -doubleOffset, 1, overline, textDecorationThickness, antialiasDecoration, isPrinting);
-    }
-    if (deco & TextDecorationLineThrough) {
-        const float lineThroughOffset = 2 * baseline / 3;
-        paintAppliedDecoration(context, FloatPoint(localOrigin) + FloatPoint(0, lineThroughOffset), width.toFloat(), doubleOffset, 0, linethrough, textDecorationThickness, antialiasDecoration, isPrinting);
+    for (const auto& decoration : decorations) {
+        if (decoration.lines() & TextDecorationUnderline) {
+            const int underlineOffset = computeUnderlineOffset(styleToUse.textUnderlinePosition(), styleToUse.fontMetrics(), &m_inlineTextBox, textDecorationThickness);
+            paintAppliedDecoration(context, FloatPoint(localOrigin) + FloatPoint(0, underlineOffset), width.toFloat(), doubleOffset, 1, decoration, textDecorationThickness, antialiasDecoration, isPrinting);
+        }
+        if (decoration.lines() & TextDecorationOverline) {
+            paintAppliedDecoration(context, FloatPoint(localOrigin), width.toFloat(), -doubleOffset, 1, decoration, textDecorationThickness, antialiasDecoration, isPrinting);
+        }
+        if (decoration.lines() & TextDecorationLineThrough) {
+            const float lineThroughOffset = 2 * baseline / 3;
+            paintAppliedDecoration(context, FloatPoint(localOrigin) + FloatPoint(0, lineThroughOffset), width.toFloat(), doubleOffset, 0, decoration, textDecorationThickness, antialiasDecoration, isPrinting);
+        }
     }
 }
 
 void InlineTextBoxPainter::paintCompositionUnderline(GraphicsContext* ctx, const LayoutPoint& boxOrigin, const CompositionUnderline& underline)
 {
     if (underline.color == Color::transparent)
         return;
 
     if (m_inlineTextBox.truncation() == cFullTruncation)
         return;
@@ skipping 59 matching lines @@
             LayoutPoint textOrigin(boxOrigin.x(), boxOrigin.y() + font.fontMetrics().ascent());
             TextPainter textPainter(pt, font, run, textOrigin, boxRect, m_inlineTextBox.isHorizontal());
 
             textPainter.paint(sPos, ePos, length, textStyle, 0);
         }
     }
 }
 
 
 } // namespace blink