Made shadows blurry (thru implementing variance mapping)

gm/shadowmaps.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 "SkPathEffect.h"
@@ skipping 58 matching lines @@
         //   - reddish directional light pointing more down than right
         //   - soft white ambient light
 
         SkLights::Builder builder;
         builder.add(SkLights::Light::MakeDirectional(SkColor3f::Make(0.2f, 0.3f, 0.4f),
                                                      SkVector3::Make(0.2f, 0.1f, 1.0f)));
         builder.add(SkLights::Light::MakeDirectional(SkColor3f::Make(0.4f, 0.3f, 0.2f),
                                                      SkVector3::Make(0.1f, 0.2f, 1.0f)));
         builder.add(SkLights::Light::MakeAmbient(SkColor3f::Make(0.4f, 0.4f, 0.4f)));
         fLights = builder.finish();
+
+        fShadowParams.fShadowRadius = 4.0f;
+        fShadowParams.fBiasingConstant = 0.3f;
+        fShadowParams.fMinVariance = 1024;
+        fShadowParams.fType = SkShadowParams::kVariance_ShadowType;
     }
 
 protected:
     static const int kWidth = 400;
     static const int kHeight = 400;
 
     SkString onShortName() override {
         return SkString("shadowmaps");
     }
 
     SkISize onISize() override {
         return SkISize::Make(kWidth, kHeight);
     }
 
     void onDraw(SkCanvas* canvas) override {
         // This picture stores the picture of the scene.
         // It's used to generate the depth maps.
         sk_sp<SkPicture> pic(make_test_picture(kWidth, kHeight));
         canvas->setLights(fLights);
-        canvas->drawShadowedPicture(pic, nullptr, nullptr);
+        canvas->drawShadowedPicture(pic, nullptr, nullptr, fShadowParams);
     }
 
 private:
     sk_sp<SkLights> fLights;
+    SkShadowParams fShadowParams;
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM(return new ShadowMapsGM;)
 }
 
 #endif