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

src/effects/SkBicubicImageFilter.cpp

 /*
  * Copyright 2013 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 "SkBicubicImageFilter.h"
 #include "SkBitmap.h"
 #include "SkColorPriv.h"
@@ skipping 66 matching lines @@
     return SkPackARGB32(SkScalarRoundToInt(a),
                         SkScalarRoundToInt(SkScalarClampMax(r, a)),
                         SkScalarRoundToInt(SkScalarClampMax(g, a)),
                         SkScalarRoundToInt(SkScalarClampMax(b, a)));
 }
 
 bool SkBicubicImageFilter::onFilterImage(Proxy* proxy,
                                          const SkBitmap& source,
                                          const SkMatrix& matrix,
                                          SkBitmap* result,
-                                         SkIPoint* loc) {
+                                         SkIPoint* offset) {
     SkBitmap src = source;
-    if (getInput(0) && !getInput(0)->filterImage(proxy, source, matrix, &src, loc)) {
+    SkIPoint srcOffset = SkIPoint::Make(0, 0);
+    if (getInput(0) && !getInput(0)->filterImage(proxy, source, matrix, &src, &srcOffset)) {
         return false;
     }
 
     if (src.config() != SkBitmap::kARGB_8888_Config) {
         return false;
     }
 
     SkAutoLockPixels alp(src);
     if (!src.getPixels()) {
         return false;
     }
 
     SkRect dstRect = SkRect::MakeWH(SkScalarMul(SkIntToScalar(src.width()), fScale.fWidth),
                                     SkScalarMul(SkIntToScalar(src.height()), fScale.fHeight));
     SkIRect dstIRect;
     dstRect.roundOut(&dstIRect);
     if (dstIRect.isEmpty()) {
         return false;
     }
     result->setConfig(src.config(), dstIRect.width(), dstIRect.height());
     result->allocPixels();
     if (!result->getPixels()) {
         return false;
     }
 
     SkRect srcRect;
     src.getBounds(&srcRect);
+    srcRect.offset(SkPoint::Make(SkIntToScalar(srcOffset.fX), SkIntToScalar(srcOffset.fY)));
     SkMatrix inverse;
     inverse.setRectToRect(dstRect, srcRect, SkMatrix::kFill_ScaleToFit);
     inverse.postTranslate(-0.5f, -0.5f);
 
     for (int y = dstIRect.fTop; y < dstIRect.fBottom; ++y) {
         SkPMColor* dptr = result->getAddr32(dstIRect.fLeft, y);
         for (int x = dstIRect.fLeft; x < dstIRect.fRight; ++x) {
             SkPoint srcPt, dstPt = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
             inverse.mapPoints(&srcPt, &dstPt, 1);
             SkScalar fractx = srcPt.fX - SkScalarFloorToScalar(srcPt.fX);
@@ skipping 24 matching lines @@
             SkPMColor s32 = *src.getAddr32(x3, y2);
             SkPMColor s2 = cubicBlend(fCoefficients, fractx, s02, s12, s22, s32);
             SkPMColor s03 = *src.getAddr32(x0, y3);
             SkPMColor s13 = *src.getAddr32(x1, y3);
             SkPMColor s23 = *src.getAddr32(x2, y3);
             SkPMColor s33 = *src.getAddr32(x3, y3);
             SkPMColor s3 = cubicBlend(fCoefficients, fractx, s03, s13, s23, s33);
             *dptr++ = cubicBlend(fCoefficients, fracty, s0, s1, s2, s3);
         }
     }
+    offset->fX = dstIRect.fLeft;
+    offset->fY = dstIRect.fTop;
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #if SK_SUPPORT_GPU
 
 bool SkBicubicImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, const SkMatrix& ctm,
                                           SkBitmap* result, SkIPoint* offset) {
     SkBitmap srcBM;
@@ skipping 21 matching lines @@
     GrPaint paint;
     paint.addColorEffect(GrBicubicEffect::Create(srcTexture, fCoefficients))->unref();
     SkRect srcRect;
     srcBM.getBounds(&srcRect);
     context->drawRectToRect(paint, dstRect, srcRect);
     return SkImageFilterUtils::WrapTexture(dst, desc.fWidth, desc.fHeight, result);
 }
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////