Split radial_gradients2 GM into two to reproduce its bug.

gm/gradients.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 "SkGradientShader.h"
 
@@ skipping 349 matching lines @@
     typedef GM INHERITED;
 };
 
 
 class RadialGradient2GM : public GM {
 public:
     RadialGradient2GM() {}
 
 protected:
     SkString onShortName() { return SkString("radial_gradient2"); }
-    virtual SkISize onISize() { return make_isize(400, 400); }
+    virtual SkISize onISize() { return make_isize(800, 400); }
     void drawBG(SkCanvas* canvas) {
         canvas->drawColor(0xFF000000);
     }
 
     // Reproduces the example given in bug 7671058.
     virtual void onDraw(SkCanvas* canvas) {
         SkPaint paint1, paint2, paint3;
         paint1.setStyle(SkPaint::kFill_Style);
         paint2.setStyle(SkPaint::kFill_Style);
         paint3.setStyle(SkPaint::kFill_Style);
 
         const SkColor sweep_colors[] =
             { 0xFFFF0000, 0xFFFFFF00, 0xFF00FF00, 0xFF00FFFF, 0xFF0000FF, 0xFFFF00FF, 0xFFFF0000 };
         const SkColor colors1[] = { 0xFFFFFFFF, 0x00000000 };
         const SkColor colors2[] = { 0xFF000000, 0x00000000 };
 
         const SkScalar cx = 200, cy = 200, radius = 150;
         SkPoint center;
         center.set(cx, cy);
 
-        SkAutoTUnref<SkShader> sweep(
-                SkGradientShader::CreateSweep(cx, cy, sweep_colors,
-                                              NULL, SK_ARRAY_COUNT(sweep_colors)));
-        SkAutoTUnref<SkShader> radial1(
-                SkGradientShader::CreateRadial(center, radius, colors1,
-                                               NULL, SK_ARRAY_COUNT(colors1),
-                                               SkShader::kClamp_TileMode));
-        SkAutoTUnref<SkShader> radial2(
-                SkGradientShader::CreateRadial(center, radius, colors2,
-                                               NULL, SK_ARRAY_COUNT(colors2),
-                                               SkShader::kClamp_TileMode));
-        paint1.setShader(sweep);
-        paint2.setShader(radial1);
-        paint3.setShader(radial2);
+        // We can either interpolate endpoints and premultiply each point (default, more precision),
+        // or premultiply the endpoints first, avoiding the need to premultiply each point (cheap).
+        const uint32_t flags[] = { 0, SkGradientShader::kInterpolateColorsInPremul_Flag };
 
-        canvas->drawCircle(cx, cy, radius, paint1);
-        canvas->drawCircle(cx, cy, radius, paint3);
-        canvas->drawCircle(cx, cy, radius, paint2);
+        for (size_t i = 0; i < SK_ARRAY_COUNT(flags); i++) {
+            SkAutoTUnref<SkShader> sweep(
+                    SkGradientShader::CreateSweep(cx, cy, sweep_colors,
+                                                  NULL, SK_ARRAY_COUNT(sweep_colors),
+                                                  NULL, flags[i]));
+            SkAutoTUnref<SkShader> radial1(
+                    SkGradientShader::CreateRadial(center, radius, colors1,
+                                                   NULL, SK_ARRAY_COUNT(colors1),
+                                                   SkShader::kClamp_TileMode,
+                                                   NULL, flags[i]));
+            SkAutoTUnref<SkShader> radial2(
+                    SkGradientShader::CreateRadial(center, radius, colors2,
+                                                   NULL, SK_ARRAY_COUNT(colors2),
+                                                   SkShader::kClamp_TileMode,
+                                                   NULL, flags[i]));
+            paint1.setShader(sweep);
+            paint2.setShader(radial1);
+            paint3.setShader(radial2);
+
+            canvas->drawCircle(cx, cy, radius, paint1);
+            canvas->drawCircle(cx, cy, radius, paint3);
+            canvas->drawCircle(cx, cy, radius, paint2);
+
+            canvas->translate(400, 0);
+        }
     }
 
 private:
     typedef GM INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 static GM* MyFactory(void*) { return new GradientsGM; }
 static GMRegistry reg(MyFactory);
 
 static GM* MyFactory2(void*) { return new GradientsDegenrate2PointGM; }
 static GMRegistry reg2(MyFactory2);
 
 static GM* MyFactory3(void*) { return new ClampedGradientsGM; }
 static GMRegistry reg3(MyFactory3);
 
 static GM* MyFactory4(void*) { return new RadialGradientGM; }
 static GMRegistry reg4(MyFactory4);
 
 static GM* MyFactory5(void*) { return new GradientsLocalPerspectiveGM; }
 static GMRegistry reg5(MyFactory5);
 
 static GM* MyFactory6(void*) { return new GradientsViewPerspectiveGM; }
 static GMRegistry reg6(MyFactory6);
 
 static GM* MyFactory7(void*) { return new RadialGradient2GM; }
 static GMRegistry reg7(MyFactory7);
 }