SkDisplacementMapEffect.h revision 0a657bbc2c6fc9daf699942e023050536d5ec95f 
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,
26                            ChannelSelectorType yChannelSelector,
27                            SkScalar scale, SkImageFilter* displacement,
28                            SkImageFilter* color = NULL,
29                            const CropRect* cropRect = NULL);
30
31    ~SkDisplacementMapEffect();
32
33    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
34
35    virtual bool onFilterImage(Proxy* proxy,
36                               const SkBitmap& src,
37                               const SkMatrix& ctm,
38                               SkBitmap* dst,
39                               SkIPoint* offset) SK_OVERRIDE;
40#if SK_SUPPORT_GPU
41    virtual bool canFilterImageGPU() const SK_OVERRIDE { return true; }
42    virtual bool filterImageGPU(Proxy* proxy, const SkBitmap& src, const SkMatrix& ctm,
43                                SkBitmap* result, SkIPoint* offset) SK_OVERRIDE;
44#endif
45
46protected:
47    explicit SkDisplacementMapEffect(SkFlattenableReadBuffer& buffer);
48    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
49
50private:
51    ChannelSelectorType fXChannelSelector;
52    ChannelSelectorType fYChannelSelector;
53    SkScalar fScale;
54    typedef SkImageFilter INHERITED;
55    SkImageFilter* getDisplacementInput() { return getInput(0); }
56    SkImageFilter* getColorInput() { return getInput(1); }
57};
58
59#endif
60