SkImage.h revision 97b6b0730dcb0feee9224ff04eb3985ca4bd0216 
1/*
2 * Copyright 2012 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 SkImage_DEFINED
9#define SkImage_DEFINED
10
11#include "SkRefCnt.h"
12#include "SkScalar.h"
13
14class SkData;
15class SkCanvas;
16class SkPaint;
17class SkShader;
18class GrContext;
19
20// need for TileMode
21#include "SkShader.h"
22
23////// EXPERIMENTAL
24
25class SkColorSpace;
26
27/**
28 *  SkImage is an abstraction for drawing a rectagle of pixels, though the
29 *  particular type of image could be actually storing its data on the GPU, or
30 *  as drawing commands (picture or PDF or otherwise), ready to be played back
31 *  into another canvas.
32 *
33 *  The content of SkImage is always immutable, though the actual storage may
34 *  change, if for example that image can be re-created via encoded data or
35 *  other means.
36 */
37class SkImage : public SkRefCnt {
38public:
39    SK_DECLARE_INST_COUNT(SkImage)
40
41    enum ColorType {
42        kAlpha_8_ColorType,
43        kRGB_565_ColorType,
44        kRGBA_8888_ColorType,
45        kBGRA_8888_ColorType,
46        kPMColor_ColorType,
47
48        kLastEnum_ColorType = kPMColor_ColorType
49    };
50
51    enum AlphaType {
52        kIgnore_AlphaType,
53        kOpaque_AlphaType,
54        kPremul_AlphaType,
55        kUnpremul_AlphaType,
56
57        kLastEnum_AlphaType = kUnpremul_AlphaType
58    };
59
60    struct Info {
61        int         fWidth;
62        int         fHeight;
63        ColorType   fColorType;
64        AlphaType   fAlphaType;
65    };
66
67    static SkImage* NewRasterCopy(const Info&, SkColorSpace*, const void* pixels, size_t rowBytes);
68    static SkImage* NewRasterData(const Info&, SkColorSpace*, SkData* pixels, size_t rowBytes);
69    static SkImage* NewEncodedData(SkData*);
70    static SkImage* NewTexture(GrTexture*);
71
72    int width() const { return fWidth; }
73    int height() const { return fHeight; }
74    uint32_t uniqueID() const { return fUniqueID; }
75
76    SkShader*   newShaderClamp() const;
77    SkShader*   newShader(SkShader::TileMode, SkShader::TileMode) const;
78
79    void draw(SkCanvas*, SkScalar x, SkScalar y, const SkPaint*);
80
81protected:
82    SkImage(int width, int height) :
83        fWidth(width),
84        fHeight(height),
85        fUniqueID(NextUniqueID()) {
86
87        SkASSERT(width >= 0);
88        SkASSERT(height >= 0);
89    }
90
91private:
92    const int       fWidth;
93    const int       fHeight;
94    const uint32_t  fUniqueID;
95
96    static uint32_t NextUniqueID();
97
98    typedef SkRefCnt INHERITED;
99};
100
101#endif
102