SkImage.h revision 72ba668db833d25ecdca4edfbefd601e508a1e62 
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;
19class GrTexture;
20
21// need for TileMode
22#include "SkShader.h"
23
24////// EXPERIMENTAL
25
26class SkColorSpace;
27
28/**
29 *  SkImage is an abstraction for drawing a rectagle of pixels, though the
30 *  particular type of image could be actually storing its data on the GPU, or
31 *  as drawing commands (picture or PDF or otherwise), ready to be played back
32 *  into another canvas.
33 *
34 *  The content of SkImage is always immutable, though the actual storage may
35 *  change, if for example that image can be re-created via encoded data or
36 *  other means.
37 */
38class SkImage : public SkRefCnt {
39public:
40    SK_DECLARE_INST_COUNT(SkImage)
41
42    enum ColorType {
43        kAlpha_8_ColorType,
44        kRGB_565_ColorType,
45        kRGBA_8888_ColorType,
46        kBGRA_8888_ColorType,
47        kPMColor_ColorType,
48
49        kLastEnum_ColorType = kPMColor_ColorType
50    };
51
52    enum AlphaType {
53        kIgnore_AlphaType,
54        kOpaque_AlphaType,
55        kPremul_AlphaType,
56        kUnpremul_AlphaType,
57
58        kLastEnum_AlphaType = kUnpremul_AlphaType
59    };
60
61    struct Info {
62        int         fWidth;
63        int         fHeight;
64        ColorType   fColorType;
65        AlphaType   fAlphaType;
66    };
67
68    static SkImage* NewRasterCopy(const Info&, SkColorSpace*, const void* pixels, size_t rowBytes);
69    static SkImage* NewRasterData(const Info&, SkColorSpace*, SkData* pixels, size_t rowBytes);
70    static SkImage* NewEncodedData(SkData*);
71    static SkImage* NewTexture(GrTexture*);
72
73    int width() const { return fWidth; }
74    int height() const { return fHeight; }
75    uint32_t uniqueID() const { return fUniqueID; }
76
77    SkShader*   newShaderClamp() const;
78    SkShader*   newShader(SkShader::TileMode, SkShader::TileMode) const;
79
80    void draw(SkCanvas*, SkScalar x, SkScalar y, const SkPaint*);
81
82protected:
83    SkImage(int width, int height) :
84        fWidth(width),
85        fHeight(height),
86        fUniqueID(NextUniqueID()) {
87
88        SkASSERT(width >= 0);
89        SkASSERT(height >= 0);
90    }
91
92private:
93    const int       fWidth;
94    const int       fHeight;
95    const uint32_t  fUniqueID;
96
97    static uint32_t NextUniqueID();
98
99    typedef SkRefCnt INHERITED;
100};
101
102#endif
103