Bug 655877 - Part 11: Ignore vertical-align and map dominant-baseline to vertical-align in SVG text frames. r=roc

layout/generic/nsFrame.cpp

@@ -7410,6 +7410,52 @@ nsIFrame::HasTerminalNewline() const
   return false;
 }
 
+static PRUint8
+ConvertSVGDominantBaselineToVerticalAlign(PRUint8 aDominantBaseline)
+{
+  switch (aDominantBaseline) {
+  case NS_STYLE_DOMINANT_BASELINE_HANGING:
+  case NS_STYLE_DOMINANT_BASELINE_TEXT_BEFORE_EDGE:
+    return NS_STYLE_VERTICAL_ALIGN_TEXT_TOP;
+  case NS_STYLE_DOMINANT_BASELINE_TEXT_AFTER_EDGE:
+  case NS_STYLE_DOMINANT_BASELINE_IDEOGRAPHIC:
+    return NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM;
+  case NS_STYLE_DOMINANT_BASELINE_CENTRAL:
+  case NS_STYLE_DOMINANT_BASELINE_MIDDLE:
+    return NS_STYLE_VERTICAL_ALIGN_MIDDLE;
+  case NS_STYLE_DOMINANT_BASELINE_AUTO:
+  case NS_STYLE_DOMINANT_BASELINE_ALPHABETIC:
+    return NS_STYLE_VERTICAL_ALIGN_BASELINE;
+  default:
+    NS_NOTREACHED("unexpected aDominantBaseline value");
+    return NS_STYLE_VERTICAL_ALIGN_BASELINE;
+  }
+}
+
+PRUint8
+nsIFrame::VerticalAlignEnum() const
+{
+  if (mState & NS_FRAME_IS_SVG_TEXT) {
+    PRUint8 dominantBaseline;
+    for (const nsIFrame* frame = this; frame; frame = frame->GetParent()) {
+      dominantBaseline = frame->GetStyleSVGReset()->mDominantBaseline;
+      if (dominantBaseline != NS_STYLE_DOMINANT_BASELINE_AUTO ||
+          frame->GetType() == nsGkAtoms::svgTextFrame) {
+        break;
+      }
+    }
+    return ConvertSVGDominantBaselineToVerticalAlign(dominantBaseline);
+  }
+
+  const nsStyleCoord& verticalAlign =
+    GetStyleContext()->GetStyleTextReset()->mVerticalAlign;
+  if (verticalAlign.GetUnit() == eStyleUnit_Enumerated) {
+    return verticalAlign.GetIntValue();
+  }
+
+  return eInvalidVerticalAlign;
+}
+
 /* static */
 void nsFrame::FillCursorInformationFromStyle(const nsStyleUserInterface* ui,
                                              nsIFrame::Cursor& aCursor)

layout/generic/nsIFrame.h

@@ -2838,6 +2838,16 @@ NS_PTR_TO_INT32(frame->Properties().Get(nsIFrame::ParagraphDepthProperty()))
   };
   bool IsVisibleConsideringAncestors(PRUint32 aFlags = 0) const;
 
+  /**
+   * Returns the vertical-align value to be used for layout, if it is one
+   * of the enumerated values.  If this is an SVG text frame, it returns a value
+   * that corresponds to the value of dominant-baseline.  If the
+   * vertical-align property has length or percentage value, this returns
+   * eInvalidVerticalAlign.
+   */
+  PRUint8 VerticalAlignEnum() const;
+  enum { eInvalidVerticalAlign = 0xFF };
+
   bool IsSVGText() const { return mState & NS_FRAME_IS_SVG_TEXT; }
 
 protected:

layout/generic/nsLineLayout.cpp

@@ -1452,11 +1452,7 @@ nsLineLayout::VerticalAlignLine()
   if (rootPFD.mFrame->GetStyleContext()->HasTextDecorationLines()) {
     for (const PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
       const nsIFrame *const f = pfd->mFrame;
-      const nsStyleCoord& vAlign =
-          f->GetStyleContext()->GetStyleTextReset()->mVerticalAlign;
-
-      if (vAlign.GetUnit() != eStyleUnit_Enumerated ||
-          vAlign.GetIntValue() != NS_STYLE_VERTICAL_ALIGN_BASELINE) {
+      if (f->VerticalAlignEnum() != NS_STYLE_VERTICAL_ALIGN_BASELINE) {
         const nscoord offset = baselineY - pfd->mBounds.y;
         f->Properties().Set(nsIFrame::LineBaselineOffset(),
                             NS_INT32_TO_PTR(offset));
@@ -1776,18 +1772,24 @@ nsLineLayout::VerticalAlignFrames(PerSpanData* psd)
     // Get vertical-align property
     const nsStyleCoord& verticalAlign =
       frame->GetStyleTextReset()->mVerticalAlign;
+    PRUint8 verticalAlignEnum = frame->VerticalAlignEnum();
 #ifdef NOISY_VERTICAL_ALIGN
     printf("  [frame]");
     nsFrame::ListTag(stdout, frame);
-    printf(": verticalAlignUnit=%d (enum == %d)\n",
+    printf(": verticalAlignUnit=%d (enum == %d",
            verticalAlign.GetUnit(),
            ((eStyleUnit_Enumerated == verticalAlign.GetUnit())
             ? verticalAlign.GetIntValue()
             : -1));
+    if (verticalAlignEnum != nsIFrame::eInvalidVerticalAlign) {
+      printf(", after SVG dominant-baseline conversion == %d",
+             verticalAlignEnum);
+    }
+    printf(")\n");
 #endif
 
-    if (verticalAlign.GetUnit() == eStyleUnit_Enumerated) {
-      switch (verticalAlign.GetIntValue()) {
+    if (verticalAlignEnum != nsIFrame::eInvalidVerticalAlign) {
+      switch (verticalAlignEnum) {
         default:
         case NS_STYLE_VERTICAL_ALIGN_BASELINE:
         {

layout/generic/nsTextFrameThebes.cpp

@@ -4566,11 +4566,7 @@ nsTextFrame::GetTextDecorations(nsPresContext* aPresContext,
     // that should be set (see nsLineLayout::VerticalAlignLine).
     if (firstBlock) {
       // At this point, fChild can't be null since TextFrames can't be blocks
-      const nsStyleCoord& vAlign =
-        fChild->GetStyleContext()->GetStyleTextReset()->mVerticalAlign;
-      if (vAlign.GetUnit() != eStyleUnit_Enumerated ||
-          vAlign.GetIntValue() != NS_STYLE_VERTICAL_ALIGN_BASELINE)
-      {
+      if (fChild->VerticalAlignEnum() != NS_STYLE_VERTICAL_ALIGN_BASELINE) {
         // Since offset is the offset in the child's coordinate space, we have
         // to undo the accumulation to bring the transform out of the block's
         // coordinate space