Re-add isIRect test for AA rect drawing

https://codereview.chromium.org/14820035/



git-svn-id: http://skia.googlecode.com/svn/trunk@9128 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index a865d81..6b98d13 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -680,11 +680,17 @@
     verts[9] = verts[1];
 }
 
+static bool isIRect(const GrRect& r) {
+    return SkScalarIsInt(r.fLeft)  && SkScalarIsInt(r.fTop) &&	  
+           SkScalarIsInt(r.fRight) && SkScalarIsInt(r.fBottom);	  
+}
+
 static bool apply_aa_to_rect(GrDrawTarget* target,
                              const GrRect& rect,
                              SkScalar strokeWidth,
                              const SkMatrix* matrix,
                              SkMatrix* combinedMatrix,
+                             GrRect* devRect,
                              bool* useVertexCoverage) {
     // we use a simple coverage ramp to do aa on axis-aligned rects
     // we check if the rect will be axis-aligned, and the rect won't land on
@@ -754,11 +760,13 @@
 #endif
     }
 
-    if (0 == rect.width() || 0 == rect.height()) {
-        return false;
-    }
+    combinedMatrix->mapRect(devRect, rect);
 
-    return true;
+    if (strokeWidth < 0) {
+        return !isIRect(*devRect);
+    } else {
+        return true;
+    }
 }
 
 void GrContext::drawRect(const GrPaint& paint,
@@ -770,12 +778,13 @@
     GrDrawTarget* target = this->prepareToDraw(&paint, BUFFERED_DRAW);
     GrDrawState::AutoStageDisable atr(fDrawState);
 
+    GrRect devRect;
     SkMatrix combinedMatrix;
     bool useVertexCoverage;
     bool needAA = paint.isAntiAlias() &&
                   !this->getRenderTarget()->isMultisampled();
     bool doAA = needAA && apply_aa_to_rect(target, rect, width, matrix,
-                                           &combinedMatrix,
+                                           &combinedMatrix, &devRect,
                                            &useVertexCoverage);
     if (doAA) {
         GrDrawState::AutoDeviceCoordDraw adcd(target->drawState());
@@ -792,12 +801,12 @@
                 strokeSize.set(SK_Scalar1, SK_Scalar1);
             }
             fAARectRenderer->strokeAARect(this->getGpu(), target,
-                                          rect, combinedMatrix,
+                                          rect, combinedMatrix, devRect,
                                           strokeSize, useVertexCoverage);
         } else {
             // filled AA rect
             fAARectRenderer->fillAARect(this->getGpu(), target,
-                                        rect, combinedMatrix,
+                                        rect, combinedMatrix, devRect,
                                         useVertexCoverage);
         }
         return;