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                                           uint32_t uniqueID = 0);
32
33    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDisplacementMapEffect)
34
35    virtual bool onFilterImage(Proxy* proxy,
36                               const SkBitmap& src,
37                               const Context& ctx,
38                               SkBitmap* dst,
39                               SkIPoint* offset) const SK_OVERRIDE;
40    virtual void computeFastBounds(const SkRect& src, SkRect* dst) const SK_OVERRIDE;
41
42    virtual bool onFilterBounds(const SkIRect& src, const SkMatrix&,
43                                SkIRect* dst) const SK_OVERRIDE;
44
45#if SK_SUPPORT_GPU
46    virtual bool canFilterImageGPU() const SK_OVERRIDE { return true; }
47    virtual bool filterImageGPU(Proxy* proxy, const SkBitmap& src, const Context& ctx,
48                                SkBitmap* result, SkIPoint* offset) const SK_OVERRIDE;
49#endif
50
51protected:
52    SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
53                            ChannelSelectorType yChannelSelector,
54                            SkScalar scale, SkImageFilter* inputs[2],
55                            const CropRect* cropRect,
56                            uint32_t uniqueID);
57#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
58    explicit SkDisplacementMapEffect(SkReadBuffer& buffer);
59#endif
60    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
61
62private:
63    ChannelSelectorType fXChannelSelector;
64    ChannelSelectorType fYChannelSelector;
65    SkScalar fScale;
66    typedef SkImageFilter INHERITED;
67    const SkImageFilter* getDisplacementInput() const { return getInput(0); }
68    const SkImageFilter* getColorInput() const { return getInput(1); }
69};
70
71#endif
72