Push sigma-based blur interface into our GMs/benches/tests/samplecode

gm/blurquickreject.cpp

 /*
  * Copyright 2013 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 "SkBlurMaskFilter.h"
@@ skipping 12 matching lines @@
 protected:
     virtual SkString onShortName() SK_OVERRIDE {
         return SkString("blurquickreject");
     }
 
     virtual SkISize onISize() SK_OVERRIDE {
         return SkISize::Make(kWidth, kHeight);
     }
 
     virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
-        static const SkScalar kBlurRadius = SkIntToScalar(20);
+        static const SkScalar kSigma = SkFloatToScalar(12.047f); 
         static const SkScalar kBoxSize = SkIntToScalar(100);
 
         SkRect clipRect = SkRect::MakeXYWH(0, 0, kBoxSize, kBoxSize);
         SkRect blurRects[] = {
-            { -kBoxSize - (kBlurRadius+1), 0, -(kBlurRadius+1), kBoxSize },
-            { 0, -kBoxSize - (kBlurRadius+1), kBoxSize, -(kBlurRadius+1) },
-            { kBoxSize+kBlurRadius+1, 0, 2*kBoxSize+kBlurRadius+1, kBoxSize },
-            { 0, kBoxSize+kBlurRadius+1, kBoxSize, 2*kBoxSize+kBlurRadius+1 }
+            { -kBoxSize - kSigma, 0, -kSigma, kBoxSize },
+            { 0, -kBoxSize - kSigma, kBoxSize, -kSigma },
+            { kBoxSize+kSigma, 0, 2*kBoxSize+kSigma, kBoxSize },
+            { 0, kBoxSize+kSigma, kBoxSize, 2*kBoxSize+kSigma }
         };
         SkColor colors[] = {
             SK_ColorRED,
             SK_ColorGREEN,
             SK_ColorBLUE,
             SK_ColorYELLOW,
         };
         SkASSERT(SK_ARRAY_COUNT(colors) == SK_ARRAY_COUNT(blurRects));
 
         SkPaint hairlinePaint;
         hairlinePaint.setStyle(SkPaint::kStroke_Style);
         hairlinePaint.setColor(SK_ColorWHITE);
         hairlinePaint.setStrokeWidth(0);
 
         SkPaint blurPaint;
         blurPaint.setFilterBitmap(true);
-        SkMaskFilter* mf = SkBlurMaskFilter::Create(kBlurRadius,
-                                                    SkBlurMaskFilter::kNormal_BlurStyle);
+        SkMaskFilter* mf = SkBlurMaskFilter::Create(SkBlurMaskFilter::kNormal_BlurStyle,
+                                                    kSigma);
         blurPaint.setMaskFilter(mf)->unref();
 
         canvas->clear(SK_ColorBLACK);
         canvas->save();
         canvas->translate(kBoxSize, kBoxSize);
         canvas->drawRect(clipRect, hairlinePaint);
         canvas->clipRect(clipRect);
         for (size_t i = 0; i < SK_ARRAY_COUNT(blurRects); ++i) {
             blurPaint.setColor(colors[i]);
             canvas->drawRect(blurRects[i], blurPaint);
             canvas->drawRect(blurRects[i], hairlinePaint);
         }
         canvas->restore();
     }
 
 private:
     static const int kWidth = 300;
     static const int kHeight = 300;
 
     typedef GM INHERITED;
 };
 
 DEF_GM( return new BlurQuickRejectGM(); )