1 
2 /*
3  * Copyright 2006 The Android Open Source Project
4  *
5  * Use of this source code is governed by a BSD-style license that can be
6  * found in the LICENSE file.
7  */
8 
9 
10 #ifndef SkBitmapProcShader_DEFINED
11 #define SkBitmapProcShader_DEFINED
12 
13 #include "SkShader.h"
14 #include "SkBitmapProcState.h"
15 #include "SkSmallAllocator.h"
16 
17 class SkBitmapProcShader : public SkShader {
18 public:
19     SkBitmapProcShader(const SkBitmap& src, TileMode tx, TileMode ty,
20                        const SkMatrix* localMatrix = NULL);
21 
22     // overrides from SkShader
23     bool isOpaque() const override;
24     BitmapType asABitmap(SkBitmap*, SkMatrix*, TileMode*) const override;
25 
26     size_t contextSize() const override;
27 
28     static bool CanDo(const SkBitmap&, TileMode tx, TileMode ty);
29 
30     SK_TO_STRING_OVERRIDE()
31     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBitmapProcShader)
32 
33 
34     bool asFragmentProcessor(GrContext*, const SkPaint&, const SkMatrix& viewM, const SkMatrix*,
35                              GrColor*, GrFragmentProcessor**) const override;
36 
37     class BitmapProcShaderContext : public SkShader::Context {
38     public:
39         // The context takes ownership of the state. It will call its destructor
40         // but will NOT free the memory.
41         BitmapProcShaderContext(const SkBitmapProcShader&, const ContextRec&, SkBitmapProcState*);
42         virtual ~BitmapProcShaderContext();
43 
44         void shadeSpan(int x, int y, SkPMColor dstC[], int count) override;
45         ShadeProc asAShadeProc(void** ctx) override;
46         void shadeSpan16(int x, int y, uint16_t dstC[], int count) override;
47 
getFlags()48         uint32_t getFlags() const override { return fFlags; }
49 
50     private:
51         SkBitmapProcState*  fState;
52         uint32_t            fFlags;
53 
54         typedef SkShader::Context INHERITED;
55     };
56 
57 protected:
58     void flatten(SkWriteBuffer&) const override;
59     Context* onCreateContext(const ContextRec&, void* storage) const override;
60 
61     SkBitmap    fRawBitmap;   // experimental for RLE encoding
62     uint8_t     fTileModeX, fTileModeY;
63 
64 private:
65     typedef SkShader INHERITED;
66 };
67 
68 // Commonly used allocator. It currently is only used to allocate up to 3 objects. The total
69 // bytes requested is calculated using one of our large shaders, its context size plus the size of
70 // an Sk3DBlitter in SkDraw.cpp
71 // Note that some contexts may contain other contexts (e.g. for compose shaders), but we've not
72 // yet found a situation where the size below isn't big enough.
73 typedef SkSmallAllocator<3, 1024> SkTBlitterAllocator;
74 
75 // If alloc is non-NULL, it will be used to allocate the returned SkShader, and MUST outlive
76 // the SkShader.
77 SkShader* SkCreateBitmapShader(const SkBitmap& src, SkShader::TileMode, SkShader::TileMode,
78                                const SkMatrix* localMatrix, SkTBlitterAllocator* alloc);
79 
80 #endif
81