Allow single-pass filters (which use asNewEffect()) to participate in the image filter DAG. This w…

src/core/SkImageFilter.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 "SkImageFilter.h"
 
 #include "SkBitmap.h"
 #include "SkFlattenableBuffers.h"
 #include "SkRect.h"
+#if SK_SUPPORT_GPU
+#include "GrContext.h"
+#include "GrTexture.h"
+#include "SkImageFilterUtils.h"
+#endif
 
 SK_DEFINE_INST_COUNT(SkImageFilter)
 
 SkImageFilter::SkImageFilter(int inputCount, SkImageFilter** inputs)
   : fInputCount(inputCount), fInputs(new SkImageFilter*[inputCount]) {
     for (int i = 0; i < inputCount; ++i) {
         fInputs[i] = inputs[i];
         SkSafeRef(fInputs[i]);
     }
 }
@@ skipping 78 matching lines @@
 bool SkImageFilter::onFilterImage(Proxy*, const SkBitmap&, const SkMatrix&,
                                   SkBitmap*, SkIPoint*) {
     return false;
 }
 
 bool SkImageFilter::canFilterImageGPU() const {
     return false;
 }
 
 bool SkImageFilter::filterImageGPU(Proxy* proxy, const SkBitmap& src, SkBitmap* result) {
-    SkASSERT(false);  // Should never be called, since canFilterImageGPU() returned false.
+#if SK_SUPPORT_GPU
+    SkBitmap input;
+    SkASSERT(fInputCount == 1);
+    if (!SkImageFilterUtils::GetInputResultGPU(getInput(0), proxy, src, &input)) {
+        return false;
+    }
+    GrTexture* srcTexture = (GrTexture*) input.getTexture();
+    SkRect rect;
+    src.getBounds(&rect);
+    GrContext* context = srcTexture->getContext();
+
+    GrTextureDesc desc;
+    desc.fFlags = kRenderTarget_GrTextureFlagBit,
+    desc.fWidth = input.width();
+    desc.fHeight = input.height();
+    desc.fConfig = kRGBA_8888_GrPixelConfig;
+
+    GrAutoScratchTexture dst(context, desc);
+    GrContext::AutoMatrix am;
+    am.setIdentity(context);
+    GrContext::AutoRenderTarget art(context, dst.texture()->asRenderTarget());
+    GrContext::AutoClip acs(context, rect);
+    SkAutoTUnref<GrEffectRef> effect(asNewEffect(srcTexture));

[bsalomon, 2013/04/08 17:52:17]

this->asNewEffect()

+    SkASSERT(effect);
+    GrPaint paint;
+    paint.colorStage(0)->setEffect(effect);
+    context->drawRect(paint, rect);
+    SkAutoTUnref<GrTexture> resultTex(dst.detach());
+    SkImageFilterUtils::WrapTexture(resultTex, input.width(), input.height(), result);
+    return true;
+#else
     return false;
+#endif
 }
 
 bool SkImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
                                    SkIRect* dst) {
     *dst = src;
     return true;
 }
 
-bool SkImageFilter::asNewEffect(GrEffectRef**, GrTexture*) const {
-    return false;
+GrEffectRef* SkImageFilter::asNewEffect(GrTexture*) const {
+    return NULL;
 }
 
 bool SkImageFilter::asColorFilter(SkColorFilter**) const {
     return false;
 }