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    };
23
24    ~SkDisplacementMapEffect();
25
26    static SkDisplacementMapEffect* Create(ChannelSelectorType xChannelSelector,
27                                           ChannelSelectorType yChannelSelector,
28                                           SkScalar scale, SkImageFilter* displacement,
29                                           SkImageFilter* color = NULL,
30                                           const CropRect* cropRect = NULL);
31
32    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
33
34    virtual bool onFilterImage(Proxy* proxy,
35                               const SkBitmap& src,
36                               const Context& ctx,
37                               SkBitmap* dst,
38                               SkIPoint* offset) const override;
39    void computeFastBounds(const SkRect& src, SkRect* dst) const override;
40
41    virtual bool onFilterBounds(const SkIRect& src, const SkMatrix&,
42                                SkIRect* dst) const override;
43
44#if SK_SUPPORT_GPU
45    bool canFilterImageGPU() const override { return true; }
46    virtual bool filterImageGPU(Proxy* proxy, const SkBitmap& src, const Context& ctx,
47                                SkBitmap* result, SkIPoint* offset) const override;
48#endif
49
50    SK_TO_STRING_OVERRIDE()
51
52protected:
53    SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
54                            ChannelSelectorType yChannelSelector,
55                            SkScalar scale, SkImageFilter* inputs[2],
56                            const CropRect* cropRect);
57    void flatten(SkWriteBuffer&) const override;
58
59private:
60    ChannelSelectorType fXChannelSelector;
61    ChannelSelectorType fYChannelSelector;
62    SkScalar fScale;
63    typedef SkImageFilter INHERITED;
64    const SkImageFilter* getDisplacementInput() const { return getInput(0); }
65    const SkImageFilter* getColorInput() const { return getInput(1); }
66};
67
68#endif
69