Revert of Moved ambient lights out of SkLight's light array

src/core/SkShadowShader.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 "SkCanvas.h"
 #include "SkReadBuffer.h"
 #include "SkShadowShader.h"
@@ skipping 93 matching lines @@
 
 class ShadowFP : public GrFragmentProcessor {
 public:
     ShadowFP(sk_sp<GrFragmentProcessor> povDepth,
              sk_sp<GrFragmentProcessor> diffuse,
              sk_sp<SkLights> lights,
              int diffuseWidth, int diffuseHeight,
              const SkShadowParams& params,
              GrContext* context) {
 
-        fAmbientColor = lights->ambientLightColor();
+        // fuse all ambient lights into a single one
+        fAmbientColor.set(0.0f, 0.0f, 0.0f);
 
         fNumNonAmbLights = 0; // count of non-ambient lights
         for (int i = 0; i < lights->numLights(); ++i) {
-            if (fNumNonAmbLights < SkShadowShader::kMaxNonAmbientLights) {
+            if (SkLights::Light::kAmbient_LightType == lights->light(i).type()) {
+                fAmbientColor += lights->light(i).color();
+            } else if (fNumNonAmbLights < SkShadowShader::kMaxNonAmbientLights) {
                 fLightColor[fNumNonAmbLights] = lights->light(i).color();
-
-                if (SkLights::Light::kDirectional_LightType == lights->light(i).type()) {
+                if (lights->light(i).type() == SkLights::Light::kPoint_LightType) {
+                    fLightDirOrPos[fNumNonAmbLights] = lights->light(i).pos();
+                    fLightIntensity[fNumNonAmbLights] = lights->light(i).intensity();
+                } else {
                     fLightDirOrPos[fNumNonAmbLights] = lights->light(i).dir();
                     fLightIntensity[fNumNonAmbLights] = 0.0f;
-                } else if (SkLights::Light::kPoint_LightType == lights->light(i).type()) {
-                    fLightDirOrPos[fNumNonAmbLights] = lights->light(i).pos();
-                    fLightIntensity[fNumNonAmbLights] = lights->light(i).intensity();
                 }
-
                 fIsPointLight[fNumNonAmbLights] =
-                        SkLights::Light::kPoint_LightType == lights->light(i).type();
+                         SkLights::Light::kPoint_LightType == lights->light(i).type();
 
                 SkImage_Base* shadowMap = ((SkImage_Base*)lights->light(i).getShadowMap());
 
                 // gets deleted when the ShadowFP is destroyed, and frees the GrTexture*
                 fTexture[fNumNonAmbLights] = sk_sp<GrTexture>(shadowMap->asTextureRef(context,
                                                            GrTextureParams::ClampNoFilter(),
                                                            SkSourceGammaTreatment::kIgnore));
                 fDepthMapAccess[fNumNonAmbLights].reset(fTexture[fNumNonAmbLights].get());
                 this->addTextureAccess(&fDepthMapAccess[fNumNonAmbLights]);
 
@@ skipping 548 matching lines @@
 
         fPovDepthContext->shadeSpan(x, y, diffuse, n);
         fDiffuseContext->shadeSpan(x, y, diffuse, n);
 
         for (int i = 0; i < n; ++i) {
 
             SkColor diffColor = SkUnPreMultiply::PMColorToColor(diffuse[i]);
 
             SkColor3f accum = SkColor3f::Make(0.0f, 0.0f, 0.0f);
             // This is all done in linear unpremul color space (each component 0..255.0f though)
-
-            accum.fX += lightShader.fLights->ambientLightColor().fX * SkColorGetR(diffColor);
-            accum.fY += lightShader.fLights->ambientLightColor().fY * SkColorGetG(diffColor);
-            accum.fZ += lightShader.fLights->ambientLightColor().fZ * SkColorGetB(diffColor);
-
             for (int l = 0; l < lightShader.fLights->numLights(); ++l) {
                 const SkLights::Light& light = lightShader.fLights->light(l);
 
-                if (SkLights::Light::kDirectional_LightType == light.type()) {
+                if (SkLights::Light::kAmbient_LightType == light.type()) {
+                    accum.fX += light.color().fX * SkColorGetR(diffColor);
+                    accum.fY += light.color().fY * SkColorGetG(diffColor);
+                    accum.fZ += light.color().fZ * SkColorGetB(diffColor);
+                } else if (SkLights::Light::kDirectional_LightType == light.type()) {
                     // scaling by fZ accounts for lighting direction
                     accum.fX += light.color().makeScale(light.dir().fZ).fX *
-                                SkColorGetR(diffColor);
+                                                        SkColorGetR(diffColor);
                     accum.fY += light.color().makeScale(light.dir().fZ).fY *
-                                SkColorGetG(diffColor);
+                                                        SkColorGetG(diffColor);
                     accum.fZ += light.color().makeScale(light.dir().fZ).fZ *
-                                SkColorGetB(diffColor);
+                                                        SkColorGetB(diffColor);
                 } else {
+                    // TODO: do point lights for raster, currently treated like ambient
                     accum.fX += light.color().fX * SkColorGetR(diffColor);
                     accum.fY += light.color().fY * SkColorGetG(diffColor);
                     accum.fZ += light.color().fZ * SkColorGetB(diffColor);
                 }
-
             }
 
             result[i] = convert(accum, SkColorGetA(diffColor));
         }
 
         result += n;
         x += n;
         count -= n;
     } while (count > 0);
 }
@@ skipping 105 matching lines @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkShadowShader)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkShadowShaderImpl)
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #endif