SkDisplacementMapEffect.h revision 781cc76e0f1ebb06e0796a9237045ae9d4bddd21 
1/*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef SkDisplacementMapEffect_DEFINED
9#define SkDisplacementMapEffect_DEFINED
10
11#include "SkImageFilter.h"
12#include "SkBitmap.h"
13
14class SK_API SkDisplacementMapEffect : public SkImageFilter {
15public:
16    enum ChannelSelectorType {
17        kUnknown_ChannelSelectorType,
18        kR_ChannelSelectorType,
19        kG_ChannelSelectorType,
20        kB_ChannelSelectorType,
21        kA_ChannelSelectorType,
22        kKeyBits = 3 // Max value is 4, so 3 bits are required at most
23    };
24
25    SkDisplacementMapEffect(ChannelSelectorType xChannelSelector, ChannelSelectorType yChannelSelector, SkScalar scale, SkImageFilter* displacement, SkImageFilter* color = NULL);
26
27    ~SkDisplacementMapEffect();
28
29    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
30
31    virtual bool onFilterImage(Proxy* proxy,
32                               const SkBitmap& src,
33                               const SkMatrix& ctm,
34                               SkBitmap* dst,
35                               SkIPoint* offset) SK_OVERRIDE;
36#if SK_SUPPORT_GPU
37    virtual bool canFilterImageGPU() const SK_OVERRIDE { return true; }
38    virtual GrTexture* filterImageGPU(Proxy* proxy, GrTexture* src, const SkRect& rect) SK_OVERRIDE;
39#endif
40
41protected:
42    explicit SkDisplacementMapEffect(SkFlattenableReadBuffer& buffer);
43    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
44
45private:
46    ChannelSelectorType fXChannelSelector;
47    ChannelSelectorType fYChannelSelector;
48    SkScalar fScale;
49    typedef SkImageFilter INHERITED;
50    SkImageFilter* getDisplacementInput() { return getInput(0); }
51    SkImageFilter* getColorInput() { return getInput(1); }
52};
53
54#endif
55