use Make instead of Create to return a shared shader

samplecode/PerlinPatch.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SampleCode.h"
 #include "SkAnimTimer.h"
 #include "SkCanvas.h"
@@ skipping 42 matching lines @@
 
     paint.setColor(SK_ColorGREEN);
     canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, right + 1, paint);
 }
 
 // These are actually half the total width and hieghts
 const SkScalar TexWidth = 100.0f;
 const SkScalar TexHeight = 100.0f;
 
 class PerlinPatchView : public SampleView {
-    SkShader* fShader0;    
-    SkShader* fShader1;    
-    SkShader* fShaderCompose;    
+    sk_sp<SkShader> fShader0;
+    sk_sp<SkShader> fShader1;
+    sk_sp<SkShader> fShaderCompose;
     SkScalar fXFreq;
     SkScalar fYFreq;
     SkScalar fSeed;
     SkPoint  fPts[SkPatchUtils::kNumCtrlPts];
     SkScalar fTexX;
     SkScalar fTexY;
     SkScalar fTexScale;
     SkMatrix fInvMatrix;
 public:
     PerlinPatchView() : fXFreq(0.025f), fYFreq(0.025f), fSeed(0.0f),
@@ skipping 15 matching lines @@
         fPts[8].set(150 * s, 350 * s);
         fPts[9].set(100 * s, 300 * s);
         fPts[10].set(50 * s, 250 * s);
         fPts[11].set(150 * s, 150 * s);
 
         const SkColor colors[SkPatchUtils::kNumCorners] = {
             0xFF5555FF, 0xFF8888FF, 0xFFCCCCFF
         };
         const SkPoint points[2] = { SkPoint::Make(0.0f, 0.0f),
                                     SkPoint::Make(100.0f, 100.0f) };
-        fShader0 = SkGradientShader::CreateLinear(points,
+        fShader0 = SkGradientShader::MakeLinear(points,
                                                   colors,
                                                   NULL,
                                                   3,
                                                   SkShader::kMirror_TileMode,
                                                   0,
                                                   NULL);
     }
 
-    virtual ~PerlinPatchView() {
-        SkSafeUnref(fShader0);
-    }
 protected:
     // overrides from SkEventSink
     bool onQuery(SkEvent* evt)  override {
         if (SampleCode::TitleQ(*evt)) {
             SampleCode::TitleR(evt, "PerlinPatch");
             return true;
         }
         return this->INHERITED::onQuery(evt);
     }
 
@@ skipping 15 matching lines @@
         const SkPoint texCoords[SkPatchUtils::kNumCorners] = {
             { fTexX - texWidth, fTexY - texHeight},
             { fTexX + texWidth, fTexY - texHeight},
             { fTexX + texWidth, fTexY + texHeight},
             { fTexX - texWidth, fTexY + texHeight}}
         ;
         
         SkAutoTUnref<SkXfermode> xfer(SkXfermode::Create(SkXfermode::kSrc_Mode));
 
         SkScalar scaleFreq = 2.0;
-        fShader1 = SkPerlinNoiseShader2::CreateImprovedNoise(fXFreq/scaleFreq, fYFreq/scaleFreq, 4,
+        fShader1 = SkPerlinNoiseShader2::MakeImprovedNoise(fXFreq/scaleFreq, fYFreq/scaleFreq, 4,
                                                              fSeed);
-        fShaderCompose = SkShader::CreateComposeShader(fShader0, fShader1, nullptr);
+        fShaderCompose = SkShader::MakeComposeShader(fShader0, fShader1, nullptr);
 
         paint.setShader(fShaderCompose);
         canvas->drawPatch(fPts, nullptr, texCoords, xfer, paint);
 
         draw_control_points(canvas, fPts);
-        SkSafeUnref(fShader1);
-        SkSafeUnref(fShaderCompose);
     }
 
     class PtClick : public Click {
     public:
         int fIndex;
         PtClick(SkView* view, int index) : Click(view), fIndex(index) {}
     };
 
     static bool hittest(const SkPoint& pt, SkScalar x, SkScalar y) {
         return SkPoint::Length(pt.fX - x, pt.fY - y) < SkIntToScalar(5);
@@ skipping 35 matching lines @@
         this->inval(nullptr);
         return true;
     }
 
 private:
     typedef SampleView INHERITED;
 };
 
 DEF_SAMPLE( return new PerlinPatchView(); )