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 
14 class SK_API SkDisplacementMapEffect : public SkImageFilter {
15 public:
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
canFilterImageGPU()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 
52 protected:
53     SkDisplacementMapEffect(ChannelSelectorType xChannelSelector,
54                             ChannelSelectorType yChannelSelector,
55                             SkScalar scale, SkImageFilter* inputs[2],
56                             const CropRect* cropRect);
57     void flatten(SkWriteBuffer&) const override;
58 
59 private:
60     ChannelSelectorType fXChannelSelector;
61     ChannelSelectorType fYChannelSelector;
62     SkScalar fScale;
63     typedef SkImageFilter INHERITED;
getDisplacementInput()64     const SkImageFilter* getDisplacementInput() const { return getInput(0); }
getColorInput()65     const SkImageFilter* getColorInput() const { return getInput(1); }
66 };
67 
68 #endif
69