Fix color bug in SkRRectsGaussianEdgeShader

gm/reveal.cpp

 /*
  * Copyright 2016 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 "SkAnimTimer.h"
 #include "SkBlurMaskFilter.h"
 #include "SkGaussianEdgeShader.h"
 #include "SkRRectsGaussianEdgeShader.h"
 #include "SkPath.h"
 #include "SkPathOps.h"
 #include "SkRRect.h"
 #include "SkStroke.h"
 
 constexpr int kNumCols = 2;
 constexpr int kNumRows = 5;
 constexpr int kCellSize = 128;
 constexpr SkScalar kPad = 8.0f;
+constexpr SkScalar kBlurRadius = 8.0f;
 constexpr SkScalar kPeriod = 8.0f;
 constexpr int kClipOffset = 32;
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 class Object {
 public:
     virtual ~Object() {}
     virtual bool asRRect(SkRRect* rr) const = 0;
     virtual SkPath asPath(SkScalar inset) const = 0;
@@ skipping 309 matching lines @@
                 // The goal is to replace this clipped draw (which clips the 
                 // shadow) with a draw using the geometric clip
                 if (kGaussianEdge_Mode == fMode) {
                     canvas->save();
                         clipObj->clip(canvas);
 
                         // Draw with GaussianEdgeShader
                         SkPaint paint;
                         paint.setAntiAlias(true);
                         // G channel is an F6.2 radius
-                        paint.setColor(SkColorSetARGB(255, 0, (unsigned char)(4*kPad), 0));
+                        paint.setColor(SkColorSetARGB(255, 0, (unsigned char)(4*kBlurRadius), 0));
                         paint.setShader(SkGaussianEdgeShader::Make());
                         drawObj->draw(canvas, paint);
                     canvas->restore();
                 } else if (kBlurMask_Mode == fMode) {
                     SkPath clippedPath;
 
-                    SkScalar sigma = kPad / 4.0f;
+                    SkScalar sigma = kBlurRadius / 4.0f;
 
                     if (clipObj->contains(drawObj->bounds())) {
                         clippedPath = drawObj->asPath(2.0f*sigma);
                     } else {
                         SkPath drawnPath = drawObj->asPath(2.0f*sigma);
                         SkPath clipPath  = clipObj->asPath(2.0f*sigma);
 
                         SkAssertResult(Op(clipPath, drawnPath, kIntersect_SkPathOp, &clippedPath));
                     }
 
                     SkPaint blurPaint;
                     blurPaint.setAntiAlias(true);
                     blurPaint.setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle, sigma));
                     canvas->drawPath(clippedPath, blurPaint);
                 } else {
                     SkASSERT(kRRectsGaussianEdge_Mode == fMode);
 
                     SkRect cover = drawObj->bounds();
                     SkAssertResult(cover.intersect(clipObj->bounds()));
 
                     SkPaint paint;
 
                     SkRRect clipRR, drawnRR;
 
                     if (clipObj->asRRect(&clipRR) && drawObj->asRRect(&drawnRR)) {
                         paint.setShader(SkRRectsGaussianEdgeShader::Make(clipRR, drawnRR,
-                                                                         kPad, 0.0f));
+                                                                         kBlurRadius));
                     }
 
                     canvas->drawRect(cover, paint);
                 }
 
                 // Draw the clip and draw objects for reference
                 SkPaint strokePaint;
                 strokePaint.setStyle(SkPaint::kStroke_Style);
                 strokePaint.setStrokeWidth(0);
                 strokePaint.setColor(SK_ColorRED);
@@ skipping 31 matching lines @@
     Mode     fMode;
     bool     fPause;
 
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM(return new RevealGM;)
 }