check for culled-out paths inside SkDraw

src/core/SkDraw.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #define __STDC_LIMIT_MACROS
 
 #include "SkDraw.h"
 #include "SkBlitter.h"
@@ skipping 999 matching lines @@
             if (scale > 0) {
                 return scale;
             }
         }
     }
     return 1;
 }
 
 void SkDraw::drawDevPath(const SkPath& devPath, const SkPaint& paint, bool drawCoverage,
                          SkBlitter* customBlitter, bool doFill) const {
+    // Do a conservative quick-reject test, since a looper or other modifier may have moved us
+    // out of range.
+    if (!devPath.isInverseFillType()) {
+        // If we're a H or V line, our bounds will be empty. So we bloat here just so we don't
+        // appear empty to the intersects call. This also gives us slop in case we're antialiasing
+        SkRect pathBounds = devPath.getBounds().makeOutset(1, 1);
+
+        if (paint.getMaskFilter()) {
+            paint.getMaskFilter()->computeFastBounds(pathBounds, &pathBounds);
+
+            // Need to outset the path to work-around a bug in blurmaskfilter. When that is fixed
+            // we can remove this hack. See skbug.com/5542
+            pathBounds.outset(7, 7);
+        }
+
+        // Now compare against the clip's bounds
+        if (!SkRect::Make(fRC->getBounds()).intersects(pathBounds)) {
+            return;
+        }
+    }
+
     SkBlitter* blitter = nullptr;
     SkAutoBlitterChoose blitterStorage;
     if (nullptr == customBlitter) {
         blitterStorage.choose(fDst, *fMatrix, paint, drawCoverage);
         blitter = blitterStorage.get();
     } else {
         blitter = customBlitter;
     }
 
     if (paint.getMaskFilter()) {
@@ skipping 1054 matching lines @@
         mask->fImage = SkMask::AllocImage(size);
         memset(mask->fImage, 0, mask->computeImageSize());
     }
 
     if (SkMask::kJustComputeBounds_CreateMode != mode) {
         draw_into_mask(*mask, devPath, style);
     }
 
     return true;
 }