1 /*
2  * Copyright 2007 The Android Open Source Project
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 SkPixelXorXfermode_DEFINED
9 #define SkPixelXorXfermode_DEFINED
10 
11 #include "SkXfermode.h"
12 
13 /** SkPixelXorXfermode implements a simple pixel xor (op ^ src ^ dst).
14     This transformation does not follow premultiplied conventions, therefore
15     this proc *always* returns an opaque color (alpha == 255). Thus it is
16     not really usefull for operating on blended colors.
17 */
18 class SK_API SkPixelXorXfermode : public SkXfermode {
19 public:
Create(SkColor opColor)20     static SkXfermode* Create(SkColor opColor) {
21         return new SkPixelXorXfermode(opColor);
22     }
23 
24 #if SK_SUPPORT_GPU
25     const GrFragmentProcessor* getFragmentProcessorForImageFilter(
26                                                     const GrFragmentProcessor* dst) const override;
27     GrXPFactory* asXPFactory() const override;
28 #endif
29 
30     SK_TO_STRING_OVERRIDE()
31     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPixelXorXfermode)
32 
33 protected:
34     void flatten(SkWriteBuffer&) const override;
35     SkPMColor xferColor(SkPMColor src, SkPMColor dst) const override;
36 
37 private:
SkPixelXorXfermode(SkColor opColor)38     explicit SkPixelXorXfermode(SkColor opColor) {
39         fOpColor = SkPreMultiplyColor(opColor | 0xFF000000);
40     }
41 
42     SkPMColor fOpColor;
43 
44     typedef SkXfermode INHERITED;
45 };
46 
47 #endif
48