Made shadows blurry (thru implementing variance mapping)

src/core/SkCanvas.cpp

Index: src/core/SkCanvas.cpp
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index 24d9506bd79ca2719440e3f0f16cd09fb833f0ca..f2f5e6c7015999a99a9dec875d760be7c97536ec 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -39,11 +39,28 @@
 #include "SkTraceEvent.h"
 
 #include <new>
+#include <SkShadowPaintFilterCanvas.h>
+#include "SkLights.h"
+
+#include "SkDrawFilter.h"
+#include "SkLights.h"
+#include "SkPictureRecorder.h"
+#include "SkSurface.h"
+#include "SkPaintFilterCanvas.h"
+#include "SkMatrix.h"
+#include "SkShadowShader.h"
+#include "SkBitmapProcShader.h"
+#include "SkNormalSource.h"
+
+
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrRenderTarget.h"
 #include "SkGrPriv.h"
+#include "SkShadowShader.h"
+#include "SkShadowMapShader.h"
+
 #endif
 
 #define RETURN_ON_NULL(ptr)     do { if (nullptr == (ptr)) return; } while (0)
@@ -3068,6 +3085,9 @@ void SkCanvas::drawShadowedPicture(const SkPicture* picture,
     this->onDrawShadowedPicture(picture, matrix, paint);
 }
 
+#include "GrDrawContext.h"
+#include "../../include/effects/SkBlurImageFilter.h"
+

[robertphillips, 2016/08/10 14:23:18]

Let's parameterize this so we can turn variance shadow maps on & off

[vjiaoblack, 2016/08/11 18:28:51]

Done.

 void SkCanvas::onDrawShadowedPicture(const SkPicture* picture,
                                      const SkMatrix* matrix,
                                      const SkPaint* paint) {
@@ -3086,46 +3106,6 @@ void SkCanvas::onDrawShadowedPicture(const SkPicture* picture,
 
     SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
 
-    for (int i = 0; i < fLights->numLights(); ++i) {
-        // skip over ambient lights; they don't cast shadows
-        // lights that have shadow maps do not need updating (because lights are immutable)
-
-        if (SkLights::Light::kAmbient_LightType == fLights->light(i).type() ||
-            fLights->light(i).getShadowMap() != nullptr) {
-            continue;
-        }
-
-        // TODO: compute the correct size of the depth map from the light properties
-        // TODO: maybe add a kDepth_8_SkColorType
-        // TODO: find actual max depth of picture
-        SkISize shMapSize = SkShadowPaintFilterCanvas::ComputeDepthMapSize(
-                                    fLights->light(i), 255,
-                                    picture->cullRect().width(),
-                                    picture->cullRect().height());
-
-        SkImageInfo info = SkImageInfo::Make(shMapSize.fWidth, shMapSize.fHeight,
-                                             kBGRA_8888_SkColorType,
-                                             kOpaque_SkAlphaType);
-
-        // Create a new surface (that matches the backend of canvas)
-        // for each shadow map
-        sk_sp<SkSurface> surf(this->makeSurface(info));
-
-        // Wrap another SPFCanvas around the surface
-        sk_sp<SkShadowPaintFilterCanvas> depthMapCanvas =
-                sk_make_sp<SkShadowPaintFilterCanvas>(surf->getCanvas());
-
-        // set the depth map canvas to have the light we're drawing.
-        SkLights::Builder builder;
-        builder.add(fLights->light(i));
-        sk_sp<SkLights> curLight = builder.finish();
-
-        depthMapCanvas->setLights(std::move(curLight));
-        depthMapCanvas->drawPicture(picture);
-
-        fLights->light(i).setShadowMap(surf->makeImageSnapshot());
-    }
-
     sk_sp<SkImage> povDepthMap;
     sk_sp<SkImage> diffuseMap;
 
@@ -3156,7 +3136,6 @@ void SkCanvas::onDrawShadowedPicture(const SkPicture* picture,
         depthMapCanvas->setLights(std::move(povLight));
 
         depthMapCanvas->drawPicture(picture);
-
         povDepthMap = surf->makeImageSnapshot();
     }
 
@@ -3173,14 +3152,67 @@ void SkCanvas::onDrawShadowedPicture(const SkPicture* picture,
         diffuseMap = surf->makeImageSnapshot();
     }
 

[robertphillips, 2016/08/10 14:23:18]

Why was this moved down?

[vjiaoblack, 2016/08/11 18:28:51]

Done.

+    for (int i = 0; i < fLights->numLights(); ++i) {
+        // skip over ambient lights; they don't cast shadows
+        // lights that have shadow maps do not need updating (because lights are immutable)
+
+        if (SkLights::Light::kAmbient_LightType == fLights->light(i).type() ||
+            fLights->light(i).getShadowMap() != nullptr) {
+            continue;
+        }
+
+        // TODO: compute the correct size of the depth map from the light properties
+        // TODO: maybe add a kDepth_8_SkColorType
+        // TODO: find actual max depth of picture
+        SkISize shMapSize = SkShadowPaintFilterCanvas::ComputeDepthMapSize(
+                                    fLights->light(i), 255,
+                                    picture->cullRect().width(),
+                                    picture->cullRect().height());
+
+        SkImageInfo info = SkImageInfo::Make(shMapSize.fWidth, shMapSize.fHeight,
+                                             kBGRA_8888_SkColorType,
+                                             kOpaque_SkAlphaType);
+
+        // Create a new surface (that matches the backend of canvas)
+        // for each shadow map
+        sk_sp<SkSurface> surf(this->makeSurface(info));
+
+        // Wrap another SPFCanvas around the surface
+        sk_sp<SkShadowPaintFilterCanvas> depthMapCanvas =
+                sk_make_sp<SkShadowPaintFilterCanvas>(surf->getCanvas());
+
+        // set the depth map canvas to have the light we're drawing.
+        SkLights::Builder builder;
+        builder.add(fLights->light(i));
+        sk_sp<SkLights> curLight = builder.finish();
+        depthMapCanvas->setLights(curLight);
+
+        depthMapCanvas->drawPicture(picture);
+        sk_sp<SkImage> depthMap = surf->makeImageSnapshot();
+
+        // we blur the variance map
+        SkPaint paint2;
+        paint2.setImageFilter(SkBlurImageFilter::Make(2.0f, 2.0f, nullptr));
+
+        SkImageInfo info2 = SkImageInfo::Make(picture->cullRect().width(),
+                                             picture->cullRect().height(),
+                                             kBGRA_8888_SkColorType,
+                                             kOpaque_SkAlphaType);
+
+        sk_sp<SkSurface> surf2(this->makeSurface(info2));
+        sk_sp<SkCanvas> depthMapCanvas2 = sk_ref_sp(surf2->getCanvas());
+
+        depthMapCanvas2->drawImage(depthMap, 0, 0, &paint2);
+
+        fLights->light(i).setShadowMap(surf2->makeImageSnapshot());
+    }
+
     SkPaint shadowPaint;
 
     sk_sp<SkShader> povDepthShader = povDepthMap->makeShader(SkShader::kClamp_TileMode,
                                                              SkShader::kClamp_TileMode);
-
     sk_sp<SkShader> diffuseShader = diffuseMap->makeShader(SkShader::kClamp_TileMode,
                                                            SkShader::kClamp_TileMode);
-
     sk_sp<SkShader> shadowShader = SkShadowShader::Make(std::move(povDepthShader),
                                                         std::move(diffuseShader),
                                                         std::move(fLights),