1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/* LIBGIMP - The GIMP Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* gimpcairo.h
* Copyright (C) 2007 Sven Neumann <sven@gimp.org>
* 2010-2012 Michael Natterer <mitch@gimp.org>
*
* This library is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <https://www.gnu.org/licenses/>.
*/
#ifndef __GIMP_CAIRO_H__
#define __GIMP_CAIRO_H__
void gimp_cairo_set_source_rgb (cairo_t *cr,
const GimpRGB *color);
void gimp_cairo_set_source_rgba (cairo_t *cr,
const GimpRGB *color);
cairo_pattern_t * gimp_cairo_checkerboard_create (cairo_t *cr,
gint size,
const GimpRGB *light,
const GimpRGB *dark);
const Babl * gimp_cairo_surface_get_format (cairo_surface_t *surface);
GeglBuffer * gimp_cairo_surface_create_buffer (cairo_surface_t *surface);
/* some useful macros for writing directly to a Cairo surface */
/**
* GIMP_CAIRO_RGB24_SET_PIXEL:
* @d: pointer to the destination buffer
* @r: red component
* @g: green component
* @b: blue component
*
* Sets a single pixel in an Cairo image surface in %CAIRO_FORMAT_RGB24.
*
* Since: 2.6
**/
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GIMP_CAIRO_RGB24_SET_PIXEL(d, r, g, b) \
G_STMT_START { d[0] = (b); d[1] = (g); d[2] = (r); } G_STMT_END
#else
#define GIMP_CAIRO_RGB24_SET_PIXEL(d, r, g, b) \
G_STMT_START { d[1] = (r); d[2] = (g); d[3] = (b); } G_STMT_END
#endif
/**
* GIMP_CAIRO_RGB24_GET_PIXEL:
* @s: pointer to the source buffer
* @r: red component
* @g: green component
* @b: blue component
*
* Gets a single pixel from a Cairo image surface in %CAIRO_FORMAT_RGB24.
*
* Since: 2.8
**/
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GIMP_CAIRO_RGB24_GET_PIXEL(s, r, g, b) \
G_STMT_START { (b) = s[0]; (g) = s[1]; (r) = s[2]; } G_STMT_END
#else
#define GIMP_CAIRO_RGB24_GET_PIXEL(s, r, g, b) \
G_STMT_START { (r) = s[1]; (g) = s[2]; (b) = s[3]; } G_STMT_END
#endif
/**
* GIMP_CAIRO_ARGB32_SET_PIXEL:
* @d: pointer to the destination buffer
* @r: red component, not pre-multiplied
* @g: green component, not pre-multiplied
* @b: blue component, not pre-multiplied
* @a: alpha component
*
* Sets a single pixel in an Cairo image surface in %CAIRO_FORMAT_ARGB32.
*
* Since: 2.6
**/
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GIMP_CAIRO_ARGB32_SET_PIXEL(d, r, g, b, a) \
G_STMT_START { \
const guint tr = (a) * (r) + 0x80; \
const guint tg = (a) * (g) + 0x80; \
const guint tb = (a) * (b) + 0x80; \
(d)[0] = (((tb) >> 8) + (tb)) >> 8; \
(d)[1] = (((tg) >> 8) + (tg)) >> 8; \
(d)[2] = (((tr) >> 8) + (tr)) >> 8; \
(d)[3] = (a); \
} G_STMT_END
#else
#define GIMP_CAIRO_ARGB32_SET_PIXEL(d, r, g, b, a) \
G_STMT_START { \
const guint tr = (a) * (r) + 0x80; \
const guint tg = (a) * (g) + 0x80; \
const guint tb = (a) * (b) + 0x80; \
(d)[0] = (a); \
(d)[1] = (((tr) >> 8) + (tr)) >> 8; \
(d)[2] = (((tg) >> 8) + (tg)) >> 8; \
(d)[3] = (((tb) >> 8) + (tb)) >> 8; \
} G_STMT_END
#endif
/**
* GIMP_CAIRO_ARGB32_GET_PIXEL:
* @s: pointer to the source buffer
* @r: red component, not pre-multiplied
* @g: green component, not pre-multiplied
* @b: blue component, not pre-multiplied
* @a: alpha component
*
* Gets a single pixel from a Cairo image surface in %CAIRO_FORMAT_ARGB32.
*
* Since: 2.8
**/
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GIMP_CAIRO_ARGB32_GET_PIXEL(s, r, g, b, a) \
G_STMT_START { \
const guint tb = (s)[0]; \
const guint tg = (s)[1]; \
const guint tr = (s)[2]; \
const guint ta = (s)[3]; \
(r) = (tr << 8) / (ta + 1); \
(g) = (tg << 8) / (ta + 1); \
(b) = (tb << 8) / (ta + 1); \
(a) = ta; \
} G_STMT_END
#else
#define GIMP_CAIRO_ARGB32_GET_PIXEL(s, r, g, b, a) \
G_STMT_START { \
const guint ta = (s)[0]; \
const guint tr = (s)[1]; \
const guint tg = (s)[2]; \
const guint tb = (s)[3]; \
(r) = (tr << 8) / (ta + 1); \
(g) = (tg << 8) / (ta + 1); \
(b) = (tb << 8) / (ta + 1); \
(a) = ta; \
} G_STMT_END
#endif
#endif /* __GIMP_CAIRO_H__ */
|
