xref: /aosp_15_r20/external/skia/src/shaders/SkImageShader.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2015 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 SkImageShader_DEFINED
9 #define SkImageShader_DEFINED
10 
11 #include "include/core/SkFlattenable.h"
12 #include "include/core/SkImage.h"
13 #include "include/core/SkM44.h"
14 #include "include/core/SkRect.h"
15 #include "include/core/SkRefCnt.h"
16 #include "include/core/SkSamplingOptions.h"
17 #include "include/core/SkTypes.h"
18 #include "src/shaders/SkShaderBase.h"
19 
20 class SkArenaAlloc;
21 class SkMatrix;
22 class SkReadBuffer;
23 class SkShader;
24 class SkWriteBuffer;
25 enum class SkTileMode;
26 struct SkStageRec;
27 
28 class SkImageShader : public SkShaderBase {
29 public:
30     static sk_sp<SkShader> Make(sk_sp<SkImage>,
31                                 SkTileMode tmx,
32                                 SkTileMode tmy,
33                                 const SkSamplingOptions&,
34                                 const SkMatrix* localMatrix,
35                                 bool clampAsIfUnpremul = false);
36 
37     static sk_sp<SkShader> MakeRaw(sk_sp<SkImage>,
38                                    SkTileMode tmx,
39                                    SkTileMode tmy,
40                                    const SkSamplingOptions&,
41                                    const SkMatrix* localMatrix);
42 
43     // TODO(skbug.com/12784): Requires SkImage to be texture backed, and created SkShader can only
44     // be used on GPU-backed surfaces.
45     static sk_sp<SkShader> MakeSubset(sk_sp<SkImage>,
46                                       const SkRect& subset,
47                                       SkTileMode tmx,
48                                       SkTileMode tmy,
49                                       const SkSamplingOptions&,
50                                       const SkMatrix* localMatrix,
51                                       bool clampAsIfUnpremul = false);
52 
53     SkImageShader(sk_sp<SkImage>,
54                   const SkRect& subset,
55                   SkTileMode tmx, SkTileMode tmy,
56                   const SkSamplingOptions&,
57                   bool raw,
58                   bool clampAsIfUnpremul);
59 
60     bool isOpaque() const override;
61 
type()62     ShaderType type() const override { return ShaderType::kImage; }
63 
64     static SkM44 CubicResamplerMatrix(float B, float C);
65 
tileModeX()66     SkTileMode tileModeX() const { return fTileModeX; }
tileModeY()67     SkTileMode tileModeY() const { return fTileModeY; }
image()68     sk_sp<SkImage> image() const { return fImage; }
sampling()69     SkSamplingOptions sampling() const { return fSampling; }
subset()70     SkRect subset() const { return fSubset; }
isRaw()71     bool isRaw() const { return fRaw; }
72 
73 private:
74     SK_FLATTENABLE_HOOKS(SkImageShader)
75 
76     void flatten(SkWriteBuffer&) const override;
77 #ifdef SK_ENABLE_LEGACY_SHADERCONTEXT
78     Context* onMakeContext(const ContextRec&, SkArenaAlloc* storage) const override;
79 #endif
80     SkImage* onIsAImage(SkMatrix*, SkTileMode*) const override;
81 
82     bool appendStages(const SkStageRec&, const SkShaders::MatrixRec&) const override;
83 
84     sk_sp<SkImage>          fImage;
85     const SkSamplingOptions fSampling;
86     const SkTileMode        fTileModeX;
87     const SkTileMode        fTileModeY;
88 
89     // TODO(skbug.com/12784): This is only supported for GPU images currently.
90     // If subset == (0,0,w,h) of the image, then no subset is applied. Subset will not be empty.
91     const SkRect            fSubset;
92 
93     const bool              fRaw;
94     const bool              fClampAsIfUnpremul;
95 
96     friend class SkShaderBase;
97     using INHERITED = SkShaderBase;
98 };
99 
100 #endif
101