add gm for 2-rects and blur

gm/blurs.cpp

Index: gm/blurs.cpp
diff --git a/gm/blurs.cpp b/gm/blurs.cpp
index ad363e425d6011fc62033cc777cc0f591c47c891..2ca1193e22e435f43fb21d9a5f7248c0ce66358a 100644
--- a/gm/blurs.cpp
+++ b/gm/blurs.cpp
@@ -1,17 +1,15 @@
-
 /*
  * 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 "SkBlurMask.h"
 #include "SkBlurMaskFilter.h"
 
-namespace skiagm {
-
-class BlursGM : public GM {
+class BlursGM : public skiagm::GM {
 public:
     BlursGM() {
         this->setBGColor(0xFFDDDDDD);
@@ -92,12 +90,45 @@ protected:
     }
 
 private:
-    typedef GM INHERITED;
+    typedef skiagm::GM INHERITED;
 };
+DEF_GM( return new BlursGM; )
+
+//////////////////////////////////////////////////////////////////////////////////////////////
+
+// exercise a special-case of blurs, which is two nested rects. These are drawn specially,
+// and possibly cached.
+//
+// in particular, we want to notice that the 2nd rect draws slightly differently, since it
+// is translated a fractional amount.
+//
+class Blur2RectsGM : public skiagm::GM {
+public:
+    SkString onShortName() SK_OVERRIDE {
+        return SkString("blur2rects");
+    }
 
-//////////////////////////////////////////////////////////////////////////////
+    SkISize onISize() SK_OVERRIDE {
+        return SkISize::Make(700, 500);
+    }
+
+    void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+        SkPaint paint;
 
-static GM* MyFactory(void*) { return new BlursGM; }
-static GMRegistry reg(MyFactory);
+        paint.setMaskFilter(SkBlurMaskFilter::Create(kNormal_SkBlurStyle,
+                                                     2.3f))->unref();
 
-}
+        SkRect outer = SkRect::MakeXYWH(10.125f, 10.125f, 100, 100);
+        SkRect inner = SkRect::MakeXYWH(20, 20, 80, 80);
+        SkPath path;
+        path.addRect(outer, SkPath::kCW_Direction);
+        path.addRect(inner, SkPath::kCCW_Direction);
+
+        canvas->drawPath(path, paint);
+        // important to translate by a factional amount (.25) to exercise a different "phase"
+        // of the same path w.r.t. the pixel grid
+        canvas->translate(SkScalarRoundToScalar(path.getBounds().width()) + 14 + 0.25f, 0);
+        canvas->drawPath(path, paint);
+    }
+};
+DEF_GM( return new Blur2RectsGM; )