Make SkImageFilter crop rects relative to the primitive origin, instead of relative to their parent

src/effects/SkLightingImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkLightingImageFilter.h"
 #include "SkBitmap.h"
 #include "SkColorPriv.h"
@@ skipping 909 matching lines @@
     buffer.writeScalar(fKD);
 }
 
 bool SkDiffuseLightingImageFilter::onFilterImage(Proxy* proxy,
                                                  const SkBitmap& source,
                                                  const SkMatrix& ctm,
                                                  SkBitmap* dst,
                                                  SkIPoint* offset) {
     SkImageFilter* input = getInput(0);
     SkBitmap src = source;
-    if (input && !input->filterImage(proxy, source, ctm, &src, offset)) {
+    SkIPoint srcOffset = SkIPoint::Make(0, 0);
+    if (input && !input->filterImage(proxy, source, ctm, &src, &srcOffset)) {
         return false;
     }
 
     if (src.config() != SkBitmap::kARGB_8888_Config) {
         return false;
     }
     SkAutoLockPixels alp(src);
     if (!src.getPixels()) {
         return false;
     }
 
     SkIRect bounds;
     src.getBounds(&bounds);
+    bounds.offset(srcOffset);
     if (!this->applyCropRect(&bounds, ctm)) {
         return false;
     }
 
     if (bounds.width() < 2 || bounds.height() < 2) {
         return false;
     }
 
     dst->setConfig(src.config(), bounds.width(), bounds.height());
     dst->allocPixels();
     if (!dst->getPixels()) {
         return false;
     }
 
     SkAutoTUnref<SkLight> transformedLight(light()->transform(ctm));
 
     DiffuseLightingType lightingType(fKD);
+    offset->fX = bounds.left();
+    offset->fY = bounds.top();
+    bounds.offset(-srcOffset);
     switch (transformedLight->type()) {
         case SkLight::kDistant_LightType:
             lightBitmap<DiffuseLightingType, SkDistantLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
         case SkLight::kPoint_LightType:
             lightBitmap<DiffuseLightingType, SkPointLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
         case SkLight::kSpot_LightType:
             lightBitmap<DiffuseLightingType, SkSpotLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
     }
 
-    offset->fX += bounds.left();
-    offset->fY += bounds.top();
     return true;
 }
 
 #if SK_SUPPORT_GPU
 bool SkDiffuseLightingImageFilter::asNewEffect(GrEffectRef** effect, GrTexture* texture, const SkMatrix& matrix, const SkIRect&) const {
     if (effect) {
         SkScalar scale = SkScalarMul(surfaceScale(), SkIntToScalar(255));
         *effect = GrDiffuseLightingEffect::Create(texture, light(), scale, matrix, kd());
     }
     return true;
@@ skipping 26 matching lines @@
     buffer.writeScalar(fShininess);
 }
 
 bool SkSpecularLightingImageFilter::onFilterImage(Proxy* proxy,
                                                   const SkBitmap& source,
                                                   const SkMatrix& ctm,
                                                   SkBitmap* dst,
                                                   SkIPoint* offset) {
     SkImageFilter* input = getInput(0);
     SkBitmap src = source;
-    if (input && !input->filterImage(proxy, source, ctm, &src, offset)) {
+    SkIPoint srcOffset = SkIPoint::Make(0, 0);
+    if (input && !input->filterImage(proxy, source, ctm, &src, &srcOffset)) {
         return false;
     }
 
     if (src.config() != SkBitmap::kARGB_8888_Config) {
         return false;
     }
     SkAutoLockPixels alp(src);
     if (!src.getPixels()) {
         return false;
     }
 
     SkIRect bounds;
     src.getBounds(&bounds);
+    bounds.offset(srcOffset);
     if (!this->applyCropRect(&bounds, ctm)) {
         return false;
     }
 
     if (bounds.width() < 2 || bounds.height() < 2) {
         return false;
     }
 
     dst->setConfig(src.config(), bounds.width(), bounds.height());
     dst->allocPixels();
     if (!dst->getPixels()) {
         return false;
     }
 
     SpecularLightingType lightingType(fKS, fShininess);
+    offset->fX = bounds.left();
+    offset->fY = bounds.top();
+    bounds.offset(-srcOffset);
     SkAutoTUnref<SkLight> transformedLight(light()->transform(ctm));
     switch (transformedLight->type()) {
         case SkLight::kDistant_LightType:
             lightBitmap<SpecularLightingType, SkDistantLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
         case SkLight::kPoint_LightType:
             lightBitmap<SpecularLightingType, SkPointLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
         case SkLight::kSpot_LightType:
             lightBitmap<SpecularLightingType, SkSpotLight>(lightingType, transformedLight, src, dst, surfaceScale(), bounds);
             break;
     }
-    offset->fX += bounds.left();
-    offset->fY += bounds.top();
     return true;
 }
 
 #if SK_SUPPORT_GPU
 bool SkSpecularLightingImageFilter::asNewEffect(GrEffectRef** effect, GrTexture* texture, const SkMatrix& matrix, const SkIRect&) const {
     if (effect) {
         SkScalar scale = SkScalarMul(surfaceScale(), SkIntToScalar(255));
         *effect = GrSpecularLightingEffect::Create(texture, light(), scale, matrix, ks(), shininess());
     }
     return true;
@@ skipping 528 matching lines @@
 
     builder->fsCodeAppendf("%s(%s)", fLightColorFunc.c_str(), surfaceToLight);
 }
 
 #endif
 
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkLightingImageFilter)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkDiffuseLightingImageFilter)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSpecularLightingImageFilter)
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END