Implementation of the displacement effect (both CPU and GPU)
TEST=Added new GM called "displacement"
Review URL: https://codereview.appspot.com/7058075
git-svn-id: http://skia.googlecode.com/svn/trunk@7182 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/effects/SkDisplacementMapEffect.h b/include/effects/SkDisplacementMapEffect.h
new file mode 100644
index 0000000..641b4cb
--- /dev/null
+++ b/include/effects/SkDisplacementMapEffect.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkDisplacementMapEffect_DEFINED
+#define SkDisplacementMapEffect_DEFINED
+
+#include "SkImageFilter.h"
+#include "SkBitmap.h"
+
+class SK_API SkDisplacementMapEffect : public SkImageFilter {
+public:
+ enum ChannelSelectorType {
+ kUnknown_ChannelSelectorType,
+ kR_ChannelSelectorType,
+ kG_ChannelSelectorType,
+ kB_ChannelSelectorType,
+ kA_ChannelSelectorType,
+ kKeyBits = 3 // Max value is 4, so 3 bits are required at most
+ };
+
+ SkDisplacementMapEffect(ChannelSelectorType xChannelSelector, ChannelSelectorType yChannelSelector, SkScalar scale, SkImageFilter* displacement, SkImageFilter* color = NULL);
+
+ ~SkDisplacementMapEffect();
+
+ SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
+
+ virtual bool onFilterImage(Proxy* proxy,
+ const SkBitmap& src,
+ const SkMatrix& ctm,
+ SkBitmap* dst,
+ SkIPoint* offset) SK_OVERRIDE;
+#if SK_SUPPORT_GPU
+ virtual bool canFilterImageGPU() const SK_OVERRIDE { return true; }
+ virtual GrTexture* filterImageGPU(Proxy* proxy, GrTexture* src, const SkRect& rect) SK_OVERRIDE;
+#endif
+
+protected:
+ explicit SkDisplacementMapEffect(SkFlattenableReadBuffer& buffer);
+ virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
+
+private:
+ ChannelSelectorType fXChannelSelector;
+ ChannelSelectorType fYChannelSelector;
+ SkScalar fScale;
+ typedef SkImageFilter INHERITED;
+ SkImageFilter* getDisplacementInput() { return getInput(0); }
+ SkImageFilter* getColorInput() { return getInput(1); }
+};
+
+#endif