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 SkColor_DEFINED
11#define SkColor_DEFINED
12
13#include "SkScalar.h"
14
15/** \file SkColor.h
16
17    Types and macros for colors
18*/
19
20/** 8-bit type for an alpha value. 0xFF is 100% opaque, 0x00 is 100% transparent.
21*/
22typedef uint8_t SkAlpha;
23/** 32 bit ARGB color value, not premultiplied. The color components are always in
24    a known order. This is different from SkPMColor, which has its bytes in a configuration
25    dependent order, to match the format of kARGB32 bitmaps. SkColor is the type used to
26    specify colors in SkPaint and in gradients.
27*/
28typedef uint32_t SkColor;
29
30/** Return a SkColor value from 8 bit component values
31*/
32static inline SkColor SkColorSetARGBInline(U8CPU a, U8CPU r, U8CPU g, U8CPU b)
33{
34    SkASSERT(a <= 255 && r <= 255 && g <= 255 && b <= 255);
35
36    return (a << 24) | (r << 16) | (g << 8) | (b << 0);
37}
38
39#define SkColorSetARGBMacro(a, r, g, b) \
40    static_cast<SkColor>( \
41        (static_cast<U8CPU>(a) << 24) | \
42        (static_cast<U8CPU>(r) << 16) | \
43        (static_cast<U8CPU>(g) << 8) | \
44        (static_cast<U8CPU>(b) << 0))
45
46/** gcc will generate static initializers for code of this form:
47 * static const SkColor kMyColor = SkColorSetARGB(0xFF, 0x01, 0x02, 0x03)
48 * if SkColorSetARGB() is a static inline, but not if it's a macro.
49 */
50#if defined(NDEBUG)
51#define SkColorSetARGB(a, r, g, b) SkColorSetARGBMacro(a, r, g, b)
52#else
53#define SkColorSetARGB(a, r, g, b) SkColorSetARGBInline(a, r, g, b)
54#endif
55
56/** Return a SkColor value from 8 bit component values, with an implied value
57    of 0xFF for alpha (fully opaque)
58*/
59#define SkColorSetRGB(r, g, b)  SkColorSetARGB(0xFF, r, g, b)
60
61/** return the alpha byte from a SkColor value */
62#define SkColorGetA(color)      (((color) >> 24) & 0xFF)
63/** return the red byte from a SkColor value */
64#define SkColorGetR(color)      (((color) >> 16) & 0xFF)
65/** return the green byte from a SkColor value */
66#define SkColorGetG(color)      (((color) >>  8) & 0xFF)
67/** return the blue byte from a SkColor value */
68#define SkColorGetB(color)      (((color) >>  0) & 0xFF)
69
70static inline SkColor SkColorSetA(SkColor c, U8CPU a) {
71    return (c & 0x00FFFFFF) | (a << 24);
72}
73
74// common colors
75
76#define SK_AlphaTRANSPARENT 0x00        //!< transparent SkAlpha value
77#define SK_AlphaOPAQUE      0xFF        //!< opaque SkAlpha value
78
79#define SK_ColorTRANSPARENT 0x00000000  //!< transparent SkColor value
80
81#define SK_ColorBLACK       0xFF000000  //!< black SkColor value
82#define SK_ColorDKGRAY      0xFF444444  //!< dark gray SkColor value
83#define SK_ColorGRAY        0xFF888888  //!< gray SkColor value
84#define SK_ColorLTGRAY      0xFFCCCCCC  //!< light gray SkColor value
85#define SK_ColorWHITE       0xFFFFFFFF  //!< white SkColor value
86
87#define SK_ColorRED         0xFFFF0000  //!< red SkColor value
88#define SK_ColorGREEN       0xFF00FF00  //!< green SkColor value
89#define SK_ColorBLUE        0xFF0000FF  //!< blue SkColor value
90#define SK_ColorYELLOW      0xFFFFFF00  //!< yellow SkColor value
91#define SK_ColorCYAN        0xFF00FFFF  //!< cyan SkColor value
92#define SK_ColorMAGENTA     0xFFFF00FF  //!< magenta SkColor value
93
94////////////////////////////////////////////////////////////////////////
95
96/** Convert RGB components to HSV.
97        hsv[0] is Hue [0 .. 360)
98        hsv[1] is Saturation [0...1]
99        hsv[2] is Value [0...1]
100    @param red  red component value [0..255]
101    @param green  green component value [0..255]
102    @param blue  blue component value [0..255]
103    @param hsv  3 element array which holds the resulting HSV components.
104*/
105SK_API void SkRGBToHSV(U8CPU red, U8CPU green, U8CPU blue, SkScalar hsv[3]);
106
107/** Convert the argb color to its HSV components.
108        hsv[0] is Hue [0 .. 360)
109        hsv[1] is Saturation [0...1]
110        hsv[2] is Value [0...1]
111    @param color the argb color to convert. Note: the alpha component is ignored.
112    @param hsv  3 element array which holds the resulting HSV components.
113*/
114static inline void SkColorToHSV(SkColor color, SkScalar hsv[3])
115{
116    SkRGBToHSV(SkColorGetR(color), SkColorGetG(color), SkColorGetB(color), hsv);
117}
118
119/** Convert HSV components to an ARGB color. The alpha component is passed through unchanged.
120        hsv[0] is Hue [0 .. 360)
121        hsv[1] is Saturation [0...1]
122        hsv[2] is Value [0...1]
123    If hsv values are out of range, they are pinned.
124    @param alpha the alpha component of the returned argb color.
125    @param hsv  3 element array which holds the input HSV components.
126    @return the resulting argb color
127*/
128SK_API SkColor SkHSVToColor(U8CPU alpha, const SkScalar hsv[3]);
129
130/** Convert HSV components to an ARGB color. The alpha component set to 0xFF.
131        hsv[0] is Hue [0 .. 360)
132        hsv[1] is Saturation [0...1]
133        hsv[2] is Value [0...1]
134    If hsv values are out of range, they are pinned.
135    @param hsv  3 element array which holds the input HSV components.
136    @return the resulting argb color
137*/
138static inline SkColor SkHSVToColor(const SkScalar hsv[3])
139{
140    return SkHSVToColor(0xFF, hsv);
141}
142
143////////////////////////////////////////////////////////////////////////
144
145/** 32 bit ARGB color value, premultiplied. The byte order for this value is
146    configuration dependent, matching the format of kARGB32 bitmaps. This is different
147    from SkColor, which is nonpremultiplied, and is always in the same byte order.
148*/
149typedef uint32_t SkPMColor;
150
151/** Return a SkPMColor value from unpremultiplied 8 bit component values
152*/
153SK_API SkPMColor SkPreMultiplyARGB(U8CPU a, U8CPU r, U8CPU g, U8CPU b);
154/** Return a SkPMColor value from a SkColor value. This is done by multiplying the color
155    components by the color's alpha, and by arranging the bytes in a configuration
156    dependent order, to match the format of kARGB32 bitmaps.
157*/
158SK_API SkPMColor SkPreMultiplyColor(SkColor c);
159
160/** Define a function pointer type for combining two premultiplied colors
161*/
162typedef SkPMColor (*SkXfermodeProc)(SkPMColor src, SkPMColor dst);
163
164/** Define a function pointer type for combining a premultiplied src color
165    and a 16bit device color.
166*/
167typedef uint16_t (*SkXfermodeProc16)(SkPMColor src, uint16_t dst);
168
169#endif
170