Bug 923193. Make transform-origin on SVG elements use the SVG bbox as the reference rectangle. r=heycam

--HG--
extra : rebase_source : f4f620acc51e14625f45b8022385d8a1112fd086

layout/base/nsDisplayList.cpp

@@ -3829,8 +3829,9 @@ nsDisplayTransform::GetFrameBoundsForTransform(const nsIFrame* aFrame)
   NS_PRECONDITION(aFrame, "Can't get the bounds of a nonexistent frame!");
 
   if (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) {
-    // TODO: SVG needs to define what percentage translations resolve against.
-    return nsRect();
+    gfxRect bbox = nsSVGUtils::GetBBox(const_cast<nsIFrame*>(aFrame));
+    return nsLayoutUtils::RoundGfxRectToAppRect(bbox,
+      aFrame->PresContext()->AppUnitsPerCSSPixel()) - aFrame->GetPosition();
   }
 
   return nsRect(nsPoint(0, 0), aFrame->GetSize());
@@ -3846,8 +3847,9 @@ nsDisplayTransform::GetFrameBoundsForTransform(const nsIFrame* aFrame)
   nsRect result;
 
   if (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) {
-    // TODO: SVG needs to define what percentage translations resolve against.
-    return result;
+    gfxRect bbox = nsSVGUtils::GetBBox(const_cast<nsIFrame*>(aFrame));
+    return nsLayoutUtils::RoundGfxRectToAppRect(bbox,
+      aFrame->PresContext()->AppUnitsPerCSSPixel()) - aFrame->GetPosition();
   }
 
   /* Iterate through the continuation list, unioning together all the
@@ -3921,47 +3923,45 @@ nsDisplayTransform::GetDeltaToMozTransformOrigin(const nsIFrame* aFrame,
                          nsDisplayTransform::GetFrameBoundsForTransform(aFrame));
 
   /* Allows us to access named variables by index. */
-  float coords[3];
-  const nscoord* dimensions[2] =
-    {&boundingRect.width, &boundingRect.height};
+  float coords[2];
+  nscoord boundingOffsets[2] = {boundingRect.x, boundingRect.y};
+  nscoord boundingDimensions[2] = {boundingRect.width, boundingRect.height};
+  nscoord frameOffsets[2] = {aFrame->GetPosition().x, aFrame->GetPosition().y};
 
   for (uint8_t index = 0; index < 2; ++index) {
     /* If the -moz-transform-origin specifies a percentage, take the percentage
      * of the size of the box.
      */
     const nsStyleCoord &coord = display->mTransformOrigin[index];
-    if (coord.GetUnit() == eStyleUnit_Calc) {
-      const nsStyleCoord::Calc *calc = coord.GetCalcValue();
+    if (coord.GetUnit() == eStyleUnit_Percent) {
       coords[index] =
-        NSAppUnitsToFloatPixels(*dimensions[index], aAppUnitsPerPixel) *
-          calc->mPercent +
-        NSAppUnitsToFloatPixels(calc->mLength, aAppUnitsPerPixel);
-    } else if (coord.GetUnit() == eStyleUnit_Percent) {
-      coords[index] =
-        NSAppUnitsToFloatPixels(*dimensions[index], aAppUnitsPerPixel) *
-        coord.GetPercentValue();
+        NSAppUnitsToFloatPixels(boundingDimensions[index], aAppUnitsPerPixel) *
+          coord.GetPercentValue() +
+        NSAppUnitsToFloatPixels(boundingOffsets[index], aAppUnitsPerPixel);
     } else {
-      NS_ABORT_IF_FALSE(coord.GetUnit() == eStyleUnit_Coord, "unexpected unit");
-      coords[index] =
-        NSAppUnitsToFloatPixels(coord.GetCoordValue(), aAppUnitsPerPixel);
-    }
-    if ((aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) &&
-        coord.GetUnit() != eStyleUnit_Percent) {
-      // <length> values represent offsets from the origin of the SVG element's
-      // user space, not the top left of its bounds, so we must adjust for that:
-      nscoord offset =
-        (index == 0) ? aFrame->GetPosition().x : aFrame->GetPosition().y;
-      coords[index] -= NSAppUnitsToFloatPixels(offset, aAppUnitsPerPixel);
+      if (coord.GetUnit() == eStyleUnit_Calc) {
+        const nsStyleCoord::Calc *calc = coord.GetCalcValue();
+        coords[index] =
+          NSAppUnitsToFloatPixels(boundingDimensions[index], aAppUnitsPerPixel) *
+            calc->mPercent +
+          NSAppUnitsToFloatPixels(calc->mLength, aAppUnitsPerPixel);
+      } else {
+        NS_ABORT_IF_FALSE(coord.GetUnit() == eStyleUnit_Coord, "unexpected unit");
+        coords[index] =
+          NSAppUnitsToFloatPixels(coord.GetCoordValue(), aAppUnitsPerPixel);
+      }
+      if (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) {
+        // <length> values represent offsets from the origin of the SVG element's
+        // user space, not the top left of its border-box, so we must
+        // convert them to be relative to the border-box.
+        coords[index] -= NSAppUnitsToFloatPixels(frameOffsets[index], aAppUnitsPerPixel);
+      }
     }
   }
 
-  coords[2] = NSAppUnitsToFloatPixels(display->mTransformOrigin[2].GetCoordValue(),
-                                      aAppUnitsPerPixel);
-  /* Adjust based on the origin of the rectangle. */
-  coords[0] += NSAppUnitsToFloatPixels(boundingRect.x, aAppUnitsPerPixel);
-  coords[1] += NSAppUnitsToFloatPixels(boundingRect.y, aAppUnitsPerPixel);
-
-  return gfxPoint3D(coords[0], coords[1], coords[2]);
+  return gfxPoint3D(coords[0], coords[1],
+                    NSAppUnitsToFloatPixels(display->mTransformOrigin[2].GetCoordValue(),
+                                            aAppUnitsPerPixel));
 }
 
 /* Returns the delta specified by the -moz-perspective-origin property.

layout/reftests/transform/reftest.list

@@ -124,3 +124,7 @@ skip-if(B2G) fails-if(Android) fuzzy-if(cocoaWidget,1,2) == stresstest-1.html st
 == table-2b.html table-2-ref.html
 # Bug 722463
 == inline-1a.html inline-1-ref.html
+== transform-origin-svg-1a.svg transform-origin-svg-1-ref.svg
+== transform-origin-svg-1b.svg transform-origin-svg-1-ref.svg
+== transform-origin-svg-2a.svg transform-origin-svg-2-ref.svg
+== transform-origin-svg-2b.svg transform-origin-svg-2-ref.svg

layout/reftests/transform/transform-origin-svg-1-ref.svg

@@ -0,0 +1,3 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<rect x='40' y='140' width='100' height='100' fill='lime'/>
+</svg>

layout/reftests/transform/transform-origin-svg-1a.svg

@@ -0,0 +1,6 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<g transform="translate(30,30)">
+  <rect x='10' y='10' width='100' height='100' fill='lime'
+        style="transform:rotate(90deg); transform-origin:left bottom;"/>
+</g>
+</svg>

layout/reftests/transform/transform-origin-svg-1b.svg

@@ -0,0 +1,7 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<g transform="translate(30,30)">
+  <rect x='10' y='10' width='100' height='100' fill='lime'
+        style="transform:rotate(90deg); transform-origin:10px 110px;
+               -webkit-transform:rotate(90deg); -webkit-transform-origin:10px 110px;"/>
+</g>
+</svg>

layout/reftests/transform/transform-origin-svg-2-ref.svg

@@ -0,0 +1,3 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<rect x='40' y='140' width='100' height='100' fill='lime' stroke-width='20' stroke='blue'/>
+</svg>

layout/reftests/transform/transform-origin-svg-2a.svg

@@ -0,0 +1,6 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<g transform="translate(30,30)">
+  <rect x='10' y='10' width='100' height='100' fill='lime' stroke-width='20' stroke='blue'
+        style="transform:rotate(90deg); transform-origin:left bottom;"/>
+</g>
+</svg>

layout/reftests/transform/transform-origin-svg-2b.svg

@@ -0,0 +1,7 @@
+<svg xmlns='http://www.w3.org/2000/svg'>
+<g transform="translate(30,30)">
+  <rect x='10' y='10' width='100' height='100' fill='lime' stroke-width='20' stroke='blue'
+        style="transform:rotate(90deg); transform-origin:10px 110px;
+               -webkit-transform:rotate(90deg); -webkit-transform-origin:10px 110px;"/>
+</g>
+</svg>

layout/svg/nsSVGTextFrame2.cpp

@@ -3687,14 +3687,16 @@ nsSVGTextFrame2::ReflowSVG()
     nsSVGEffects::UpdateEffects(this);
   }
 
+  // Now unset the various reflow bits. Do this before calling
+  // FinishAndStoreOverflow since FinishAndStoreOverflow can require glyph
+  // positions (to resolve transform-origin).
+  mState &= ~(NS_FRAME_FIRST_REFLOW | NS_FRAME_IS_DIRTY |
+              NS_FRAME_HAS_DIRTY_CHILDREN);
+
   nsRect overflow = nsRect(nsPoint(0,0), mRect.Size());
   nsOverflowAreas overflowAreas(overflow, overflow);
   FinishAndStoreOverflow(overflowAreas, mRect.Size());
 
-  // Now unset the various reflow bits:
-  mState &= ~(NS_FRAME_FIRST_REFLOW | NS_FRAME_IS_DIRTY |
-              NS_FRAME_HAS_DIRTY_CHILDREN);
-
   // XXX nsSVGContainerFrame::ReflowSVG only looks at its nsISVGChildFrame
   // children, and calls ConsiderChildOverflow on them.  Does it matter
   // that ConsiderChildOverflow won't be called on our children?
@@ -3729,9 +3731,22 @@ nsSVGTextFrame2::GetBBoxContribution(const gfxMatrix &aToBBoxUserspace,
 {
   NS_ASSERTION(GetFirstPrincipalChild(), "must have a child frame");
 
+  SVGBBox bbox;
+  nsIFrame* kid = GetFirstPrincipalChild();
+  if (kid && NS_SUBTREE_DIRTY(kid)) {
+    // Return an empty bbox if our kid's subtree is dirty. This may be called
+    // in that situation, e.g. when we're building a display list after an
+    // interrupted reflow. This can also be called during reflow before we've
+    // been reflowed, e.g. if an earlier sibling is calling FinishAndStoreOverflow and
+    // needs our parent's perspective matrix, which depends on the SVG bbox
+    // contribution of this frame. In the latter situation, when all siblings have
+    // been reflowed, the parent will compute its perspective and rerun
+    // FinishAndStoreOverflow for all its children.
+    return bbox;
+  }
+
   UpdateGlyphPositioning();
 
-  SVGBBox bbox;
   nsPresContext* presContext = PresContext();
 
   TextRenderedRunIterator it(this);

layout/svg/svg.css

@@ -51,7 +51,7 @@ foreignObject {
   text-indent: 0;
 }
 
-/* Set |transform-origin:0% 0%;| for all SVG elements except outer-<svg>,
+/* Set |transform-origin:0 0;| for all SVG elements except outer-<svg>,
    noting that 'svg' as a child of 'foreignObject' counts as outer-<svg>.
 */
 *:not(svg),