Get OffsetImageFilter really working with SkSpecialImages

src/effects/SkOffsetImageFilter.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 "SkOffsetImageFilter.h"
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkDevice.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkMatrix.h"
 #include "SkPaint.h"
+#include "SkSpecialImage.h"
+#include "SkSpecialSurface.h"
+
+SkSpecialImage* SkOffsetImageFilter::onFilterImage(SkSpecialImage* srcIn,
+                                                   const Context& ctx,
+                                                   SkIPoint* offset) const {
+    SkIPoint srcOffset = SkIPoint::Make(0, 0);
+    SkAutoTUnref<SkSpecialImage> src(this->filterInput(0, srcIn, ctx, &srcOffset));
+    if (!src) {
+        return nullptr;
+    }
+
+    SkVector vec;
+    ctx.ctm().mapVectors(&vec, &fOffset, 1);
+
+    if (!this->cropRectIsSet()) {
+        offset->fX = srcOffset.fX + SkScalarRoundToInt(vec.fX);
+        offset->fY = srcOffset.fY + SkScalarRoundToInt(vec.fY);
+        return src.release();
+    } else {
+        SkIRect bounds;
+        SkIRect srcBounds = SkIRect::MakeWH(srcIn->width(), srcIn->height());
+        srcBounds.offset(srcOffset);
+        if (!this->applyCropRect(ctx, srcBounds, &bounds)) {
+            return false;
+        }
+
+        SkImageInfo info = SkImageInfo::MakeN32(bounds.width(), bounds.height(),
+                                                kPremul_SkAlphaType);
+        SkAutoTUnref<SkSpecialSurface> surf(src->newSurface(info));
+        if (!surf) {
+            return nullptr;
+        }
+
+        SkCanvas* canvas = surf->getCanvas();
+
+        canvas->clear(0x0);
+
+        SkPaint paint;
+        paint.setXfermodeMode(SkXfermode::kSrc_Mode);
+        canvas->translate(SkIntToScalar(srcOffset.fX - bounds.fLeft),
+                          SkIntToScalar(srcOffset.fY - bounds.fTop));
+
+        src->draw(canvas, vec.x(), vec.y(), &paint);
+
+        offset->fX = bounds.fLeft;
+        offset->fY = bounds.fTop;
+        return surf->newImageSnapshot();
+    }
+}
 
 bool SkOffsetImageFilter::onFilterImageDeprecated(Proxy* proxy, const SkBitmap& source,
                                                   const Context& ctx,
                                                   SkBitmap* result,
                                                   SkIPoint* offset) const {
-    SkBitmap src = source;
-    SkIPoint srcOffset = SkIPoint::Make(0, 0);
-    if (!cropRectIsSet()) {
-        if (!this->filterInputDeprecated(0, proxy, source, ctx, &src, &srcOffset)) {
-            return false;
-        }
+    SkAutoTUnref<SkSpecialImage> specialSrc(SkSpecialImage::internal_fromBM(proxy, source));
+    if (!specialSrc) {
+        return false;
+    }
 
-        SkVector vec;
-        ctx.ctm().mapVectors(&vec, &fOffset, 1);
+    SkAutoTUnref<SkSpecialImage> tmp(this->onFilterImage(specialSrc, ctx, offset));
+    if (!tmp) {
+        return false;
+    }
 
-        offset->fX = srcOffset.fX + SkScalarRoundToInt(vec.fX);
-        offset->fY = srcOffset.fY + SkScalarRoundToInt(vec.fY);
-        *result = src;
-    } else {
-        if (!this->filterInputDeprecated(0, proxy, source, ctx, &src, &srcOffset)) {
-            return false;
-        }
-
-        SkIRect bounds;
-        SkIRect srcBounds = src.bounds();
-        srcBounds.offset(srcOffset);
-        if (!this->applyCropRect(ctx, srcBounds, &bounds)) {
-            return false;
-        }
-
-        SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(bounds.width(), bounds.height()));
-        if (nullptr == device.get()) {
-            return false;
-        }
-        SkCanvas canvas(device);
-        SkPaint paint;
-        paint.setXfermodeMode(SkXfermode::kSrc_Mode);
-        canvas.translate(SkIntToScalar(srcOffset.fX - bounds.fLeft),
-                         SkIntToScalar(srcOffset.fY - bounds.fTop));
-        SkVector vec;
-        ctx.ctm().mapVectors(&vec, &fOffset, 1);
-        canvas.drawBitmap(src, vec.x(), vec.y(), &paint);
-        *result = device->accessBitmap(false);
-        offset->fX = bounds.fLeft;
-        offset->fY = bounds.fTop;
-    }
-    return true;
+    return tmp->internal_getBM(result);
 }
 
 void SkOffsetImageFilter::computeFastBounds(const SkRect& src, SkRect* dst) const {
     if (getInput(0)) {
         getInput(0)->computeFastBounds(src, dst);
     } else {
         *dst = src;
     }
     dst->offset(fOffset.fX, fOffset.fY);
 }
@@ skipping 32 matching lines @@
 void SkOffsetImageFilter::toString(SkString* str) const {
     str->appendf("SkOffsetImageFilter: (");
     str->appendf("offset: (%f, %f) ", fOffset.fX, fOffset.fY);
     str->append("input: (");
     if (this->getInput(0)) {
         this->getInput(0)->toString(str);
     }
     str->append("))");
 }
 #endif