Bug 1233632 - Moz2Dify GetBlurAndSpreadRadius(). r=dholbert.

The CurrentMatrix()-to-GetTransform() change in GetBlurAndSpreadRadius() is
valid because the operations performed on the resulting |transform| only
consult the _11, _12, _21 and _22 members; not the _31 and _32 members (which
are different in gfxContext vs. DrawTarget).

--HG--
extra : rebase_source : 4f40eb223e3e2153607c9c336fc1c850d0e1776f

layout/base/nsCSSRendering.cpp

@@ -5408,7 +5408,7 @@ nsContextBoxBlur::Init(const nsRect& aRect, nscoord aSpreadRadius,
 
   IntSize blurRadius;
   IntSize spreadRadius;
-  GetBlurAndSpreadRadius(aDestinationCtx, aAppUnitsPerDevPixel,
+  GetBlurAndSpreadRadius(aDestinationCtx->GetDrawTarget(), aAppUnitsPerDevPixel,
                          aBlurRadius, aSpreadRadius,
                          blurRadius, spreadRadius);
 
@@ -5558,7 +5558,7 @@ nsContextBoxBlur::BlurRectangle(gfxContext* aDestinationCtx,
 }
 
 /* static */ void
-nsContextBoxBlur::GetBlurAndSpreadRadius(gfxContext* aDestinationCtx,
+nsContextBoxBlur::GetBlurAndSpreadRadius(DrawTarget* aDestDrawTarget,
                                          int32_t aAppUnitsPerDevPixel,
                                          nscoord aBlurRadius,
                                          nscoord aSpreadRadius,
@@ -5566,16 +5566,15 @@ nsContextBoxBlur::GetBlurAndSpreadRadius(gfxContext* aDestinationCtx,
                                          IntSize& aOutSpreadRadius,
                                          bool aConstrainSpreadRadius)
 {
-  gfxFloat scaleX = 1;
-  gfxFloat scaleY = 1;
-
   // Do blurs in device space when possible.
   // Chrome/Skia always does the blurs in device space
   // and will sometimes get incorrect results (e.g. rotated blurs)
-  gfxMatrix transform = aDestinationCtx->CurrentMatrix();
+  Matrix transform = aDestDrawTarget->GetTransform();
   // XXX: we could probably handle negative scales but for now it's easier just to fallback
+  gfxFloat scaleX, scaleY;
   if (transform.HasNonAxisAlignedTransform() || transform._11 <= 0.0 || transform._22 <= 0.0) {
-    transform = gfxMatrix();
+    scaleX = 1;
+    scaleY = 1;
   } else {
     scaleX = transform._11;
     scaleY = transform._22;
@@ -5617,7 +5616,7 @@ nsContextBoxBlur::InsetBoxBlur(gfxContext* aDestinationCtx,
   IntSize spreadRadius;
   // Convert the blur and spread radius to device pixels
   bool constrainSpreadRadius = false;
-  GetBlurAndSpreadRadius(aDestinationCtx, aAppUnitsPerDevPixel,
+  GetBlurAndSpreadRadius(aDestinationCtx->GetDrawTarget(), aAppUnitsPerDevPixel,
                          aBlurRadiusAppUnits, aSpreadDistanceAppUnits,
                          blurRadius, spreadRadius, constrainSpreadRadius);
 

layout/base/nsCSSRendering.h

@@ -849,6 +849,7 @@ protected:
  */
 class nsContextBoxBlur {
   typedef mozilla::gfx::Color Color;
+  typedef mozilla::gfx::DrawTarget DrawTarget;
   typedef mozilla::gfx::RectCornerRadii RectCornerRadii;
 
 public:
@@ -997,7 +998,7 @@ public:
                     mozilla::gfx::Point aShadowOffset);
 
 protected:
-  static void GetBlurAndSpreadRadius(gfxContext* aContext,
+  static void GetBlurAndSpreadRadius(DrawTarget* aDestDrawTarget,
                                      int32_t aAppUnitsPerDevPixel,
                                      nscoord aBlurRadius,
                                      nscoord aSpreadRadius,