Implement crop rect support for the merge image filter.

src/effects/SkMergeImageFilter.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 "SkMergeImageFilter.h"
 #include "SkCanvas.h"
 #include "SkDevice.h"
@@ skipping 21 matching lines @@
         int inputCount = countInputs();
         for (int i = 0; i < inputCount; ++i) {
             fModes[i] = SkToU8(modes[i]);
         }
     } else {
         fModes = NULL;
     }
 }
 
 SkMergeImageFilter::SkMergeImageFilter(SkImageFilter* first, SkImageFilter* second,
-                                       SkXfermode::Mode mode) : INHERITED(first, second) {
+                                       SkXfermode::Mode mode,
+                                       const SkIRect* cropRect) : INHERITED(first, second, cropRect) {
     if (SkXfermode::kSrcOver_Mode != mode) {
         SkXfermode::Mode modes[] = { mode, mode };
         this->initModes(modes);
     } else {
         fModes = NULL;
     }
 }
 
 SkMergeImageFilter::SkMergeImageFilter(SkImageFilter* filters[], int count,
-                                       const SkXfermode::Mode modes[]) : INHERITED(count, filters) {
+                                       const SkXfermode::Mode modes[],
+                                       const SkIRect* cropRect) : INHERITED(count, filters, cropRect) {
     this->initModes(modes);
 }
 
 SkMergeImageFilter::~SkMergeImageFilter() {
 
     if (fModes != SkTCast<uint8_t*>(fStorage)) {
         sk_free(fModes);
     }
 }
 
@@ skipping 29 matching lines @@
     return true;
 }
 
 bool SkMergeImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
                                        const SkMatrix& ctm,
                                        SkBitmap* result, SkIPoint* loc) {
     if (countInputs() < 1) {
         return false;
     }
 
-    const SkIRect srcBounds = SkIRect::MakeXYWH(loc->x(), loc->y(),
-                                                src.width(), src.height());
     SkIRect bounds;
-    if (!this->filterBounds(srcBounds, ctm, &bounds)) {
+    src.getBounds(&bounds);
+    if (!this->applyCropRect(&bounds, ctm)) {
         return false;
     }
 
     const int x0 = bounds.left();
     const int y0 = bounds.top();
 
     SkAutoTUnref<SkBaseDevice> dst(proxy->createDevice(bounds.width(), bounds.height()));
     if (NULL == dst) {
         return false;
     }
     SkCanvas canvas(dst);
     SkPaint paint;
 
     int inputCount = countInputs();
     for (int i = 0; i < inputCount; ++i) {
         SkBitmap tmp;
         const SkBitmap* srcPtr;
-        SkIPoint pos = *loc;
+        SkIPoint pos = SkIPoint::Make(0, 0);
         SkImageFilter* filter = getInput(i);
         if (filter) {
             if (!filter->filterImage(proxy, src, ctm, &tmp, &pos)) {
                 return false;
             }
             srcPtr = &tmp;
         } else {
             srcPtr = &src;
         }
 
         if (fModes) {
             paint.setXfermodeMode((SkXfermode::Mode)fModes[i]);
         } else {
             paint.setXfermode(NULL);
         }
         canvas.drawSprite(*srcPtr, pos.x() - x0, pos.y() - y0, &paint);
     }
 
-    loc->set(bounds.left(), bounds.top());
+    loc->fX += bounds.left();
+    loc->fY += bounds.top();
     *result = dst->accessBitmap(false);
     return true;
 }
 
 void SkMergeImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 
     buffer.writeBool(fModes != NULL);
     if (fModes) {
         buffer.writeByteArray(fModes, countInputs() * sizeof(fModes[0]));
     }
 }
 
 SkMergeImageFilter::SkMergeImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
     bool hasModes = buffer.readBool();
     if (hasModes) {
         this->initAllocModes();
         SkASSERT(buffer.getArrayCount() == countInputs() * sizeof(fModes[0]));
         buffer.readByteArray(fModes);
     } else {
         fModes = 0;
     }
 }