From 1f88d8036d88b9f79e6b5dd16ee67e51d2d8709b Mon Sep 17 00:00:00 2001
From: Jonathan Watt <jwatt@jwatt.org>
Date: Fri, 15 Jun 2012 04:02:27 +0100
Subject: [PATCH] Bug 764813 - Avoid using gfxContext::SetMatrix in SVG code
 where possible. r=Bas.

---
 layout/svg/base/src/nsSVGGlyphFrame.cpp       |  4 +---
 layout/svg/base/src/nsSVGIntegrationUtils.cpp |  8 ++------
 layout/svg/base/src/nsSVGUtils.cpp            | 17 ++++++++---------
 3 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/layout/svg/base/src/nsSVGGlyphFrame.cpp b/layout/svg/base/src/nsSVGGlyphFrame.cpp
index 102446e8e414..703e7670c473 100644
--- a/layout/svg/base/src/nsSVGGlyphFrame.cpp
+++ b/layout/svg/base/src/nsSVGGlyphFrame.cpp
@@ -317,8 +317,7 @@ nsSVGGlyphFrame::PaintSVG(nsRenderingContext *aContext,
   }
 
   if (renderMode != SVGAutoRenderState::NORMAL) {
-
-    gfxMatrix matrix = gfx->CurrentMatrix();
+    gfxContextMatrixAutoSaveRestore matrixAutoSaveRestore(gfx);
     SetupGlobalTransform(gfx);
 
     CharacterIterator iter(this, true);
@@ -336,7 +335,6 @@ nsSVGGlyphFrame::PaintSVG(nsRenderingContext *aContext,
       DrawCharacters(&iter, gfx, gfxFont::GLYPH_PATH);
     }
 
-    gfx->SetMatrix(matrix);
     return NS_OK;
   }
 
diff --git a/layout/svg/base/src/nsSVGIntegrationUtils.cpp b/layout/svg/base/src/nsSVGIntegrationUtils.cpp
index 017ba377d3f7..48089436aad9 100644
--- a/layout/svg/base/src/nsSVGIntegrationUtils.cpp
+++ b/layout/svg/base/src/nsSVGIntegrationUtils.cpp
@@ -250,7 +250,7 @@ nsSVGIntegrationUtils::PaintFramesWithEffects(nsRenderingContext* aCtx,
   }
 
   gfxContext* gfx = aCtx->ThebesContext();
-  gfxMatrix savedCTM = gfx->CurrentMatrix();
+  gfxContextMatrixAutoSaveRestore matrixAutoSaveRestore(gfx);
 
   //SVGAutoRenderState autoRenderState(aCtx, SVGAutoRenderState::NORMAL);
 
@@ -286,7 +286,7 @@ nsSVGIntegrationUtils::PaintFramesWithEffects(nsRenderingContext* aCtx,
     nsIntRect r = (aDirtyRect - userSpaceRect.TopLeft()).ToOutsidePixels(appUnitsPerDevPixel);
     filterFrame->FilterPaint(aCtx, aEffectsFrame, &paint, &r);
   } else {
-    gfx->SetMatrix(savedCTM);
+    gfx->SetMatrix(matrixAutoSaveRestore.Matrix());
     aInnerList->PaintForFrame(aBuilder, aCtx, aEffectsFrame,
                               nsDisplayList::PAINT_DEFAULT);
     aCtx->Translate(userSpaceRect.TopLeft());
@@ -298,7 +298,6 @@ nsSVGIntegrationUtils::PaintFramesWithEffects(nsRenderingContext* aCtx,
 
   /* No more effects, we're done. */
   if (!complexEffects) {
-    gfx->SetMatrix(savedCTM);
     return;
   }
 
@@ -334,7 +333,6 @@ nsSVGIntegrationUtils::PaintFramesWithEffects(nsRenderingContext* aCtx,
   }
 
   gfx->Restore();
-  gfx->SetMatrix(savedCTM);
 }
 
 gfxMatrix
@@ -420,7 +418,6 @@ PaintFrameCallback::operator()(gfxContext* aContext,
   aContext->NewPath();
   aContext->Rectangle(aFillRect);
   aContext->Clip();
-  gfxMatrix savedMatrix(aContext->CurrentMatrix());
 
   aContext->Multiply(gfxMatrix(aTransform).Invert());
 
@@ -450,7 +447,6 @@ PaintFrameCallback::operator()(gfxContext* aContext,
                             nsLayoutUtils::PAINT_IN_TRANSFORM |
                             nsLayoutUtils::PAINT_ALL_CONTINUATIONS);
 
-  aContext->SetMatrix(savedMatrix);
   aContext->Restore();
 
   mFrame->RemoveStateBits(NS_FRAME_DRAWING_AS_PAINTSERVER);
diff --git a/layout/svg/base/src/nsSVGUtils.cpp b/layout/svg/base/src/nsSVGUtils.cpp
index e422a6bb3092..488211db2832 100644
--- a/layout/svg/base/src/nsSVGUtils.cpp
+++ b/layout/svg/base/src/nsSVGUtils.cpp
@@ -1407,15 +1407,15 @@ nsSVGUtils::HitTestRect(const gfxMatrix &aMatrix,
                         float aRX, float aRY, float aRWidth, float aRHeight,
                         float aX, float aY)
 {
-  if (aMatrix.IsSingular()) {
+  gfxRect rect(aRX, aRY, aRWidth, aRHeight);
+  if (rect.IsEmpty() || aMatrix.IsSingular()) {
     return false;
   }
-  gfxContext ctx(gfxPlatform::GetPlatform()->ScreenReferenceSurface());
-  ctx.SetMatrix(aMatrix);
-  ctx.NewPath();
-  ctx.Rectangle(gfxRect(aRX, aRY, aRWidth, aRHeight));
-  ctx.IdentityMatrix();
-  return ctx.PointInFill(gfxPoint(aX, aY));
+  gfxMatrix toRectSpace = aMatrix;
+  toRectSpace.Invert();
+  gfxPoint p = toRectSpace.Transform(gfxPoint(aX, aY));
+  return rect.x <= p.x && p.x <= rect.XMost() &&
+         rect.y <= p.y && p.y <= rect.YMost();
 }
 
 gfxRect
@@ -1518,10 +1518,9 @@ nsSVGUtils::SetClipRect(gfxContext *aContext,
   if (aCTM.IsSingular())
     return;
 
-  gfxMatrix oldMatrix = aContext->CurrentMatrix();
+  gfxContextMatrixAutoSaveRestore matrixAutoSaveRestore(aContext);
   aContext->Multiply(aCTM);
   aContext->Clip(aRect);
-  aContext->SetMatrix(oldMatrix);
 }
 
 void