Fix for nested rect drawing bug

src/gpu/GrContext.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrContext.h"
@@ skipping 993 matching lines @@
                  !target->getDrawState().getRenderTarget()->isMultisampled() &&
                  !disable_coverage_aa_for_blend(target);
 
     if (!fOvalRenderer->drawOval(target, this, useAA, oval, stroke)) {
         SkPath path;
         path.addOval(oval);
         this->internalDrawPath(target, useAA, path, stroke);
     }
 }
 
-namespace {
-
 // Can 'path' be drawn as a pair of filled nested rectangles?
 static bool is_nested_rects(GrDrawTarget* target,
                             const SkPath& path,
                             const SkStrokeRec& stroke,
                             SkRect rects[2],
                             bool* useVertexCoverage) {
     SkASSERT(stroke.isFillStyle());
 
     if (path.isInverseFillType()) {
         return false;
@@ skipping 14 matching lines @@
         } else {
             *useVertexCoverage = true;
         }
     }
 
     SkPath::Direction dirs[2];
     if (!path.isNestedRects(rects, dirs)) {
         return false;
     }
 
-    if (SkPath::kWinding_FillType == path.getFillType()) {
+    if (SkPath::kWinding_FillType == path.getFillType() && dirs[0] == dirs[1]) {
         // The two rects need to be wound opposite to each other
-        return dirs[0] != dirs[1];
-    } else {
-        return true;
+        return false;
     }
+
+    // Right now, nested rects where the margin is not the same width
+    // all around do not render correctly
+    const SkScalar* outer = rects[0].asScalars();
+    const SkScalar* inner = rects[1].asScalars();
+
+    SkScalar margin = SkScalarAbs(outer[0] - inner[0]);
+    for (int i = 1; i < 4; ++i) {
+        SkScalar temp = SkScalarAbs(outer[i] - inner[i]);
+        if (!SkScalarNearlyEqual(margin, temp)) {
+            return false;
+        }
+    }
+
+    return true;
 }
 
-};
-
 void GrContext::drawPath(const GrPaint& paint, const SkPath& path, const SkStrokeRec& stroke) {
 
     if (path.isEmpty()) {
        if (path.isInverseFillType()) {
            this->drawPaint(paint);
        }
        return;
     }
 
     // Note that internalDrawPath may sw-rasterize the path into a scratch texture.
@@ skipping 664 matching lines @@
         return NULL;
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 #if GR_CACHE_STATS
 void GrContext::printCacheStats() const {
     fTextureCache->printStats();
 }
 #endif