fine-tune tolerance for pinchy quads in stroker

gm/aaclip.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 "gm.h"
 #include "SkCanvas.h"
 #include "SkPath.h"
 
+static void test_quadstroke(SkCanvas* canvas) {
+    SkPath path;
+    path.moveTo(6, 0);
+    path.quadTo(150, 150, 0, 6);
+
+    SkPaint paint;
+    
+    paint.setAntiAlias(true);
+    paint.setStyle(SkPaint::kStroke_Style);
+    canvas->translate(20, 20);
+
+#if 1
+    canvas->drawPath(path, paint);
+    canvas->translate(100, 0);
+#endif
+    
+    paint.setStrokeWidth(1.01f);
+    canvas->drawPath(path, paint);
+}
+
 static void draw_conic(SkCanvas* canvas, SkScalar weight, const SkPaint& paint) {
     SkPath path;
     path.moveTo(100, 100);
     path.conicTo(300, 100, 300, 300, weight);
     canvas->drawPath(path, paint);
 }
 
 static void test_conic(SkCanvas* canvas) {
     SkPaint paint;
     paint.setAntiAlias(true);
@@ skipping 224 matching lines @@
 protected:
     virtual SkString onShortName() SK_OVERRIDE {
         return SkString("aaclip");
     }
 
     virtual SkISize onISize() SK_OVERRIDE {
         return SkISize::Make(640, 480);
     }
 
     virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+        if (false) { test_quadstroke(canvas); return; }
         if (false) { test_conic(canvas); return; }
         if (false) {
             SkRect bounds;
             canvas->getClipBounds(&bounds);
             test_shallow_gradient(canvas, bounds.width(), bounds.height()); return;
         }
         if (false) {
             test_giant_dash(canvas); return;
         }
         if (false) {
@@ skipping 24 matching lines @@
         draw_rect_tests(canvas);
     }
 
     virtual uint32_t onGetFlags() const { return kSkipPipe_Flag; }
 
 private:
     typedef skiagm::GM INHERITED;
 };
 
 DEF_GM( return SkNEW(AAClipGM); )