1#!/usr/bin/env python
2
3CopyRight = '''
4/**************************************************************************
5 *
6 * Copyright 2010 VMware, Inc.
7 * All Rights Reserved.
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the
11 * "Software"), to deal in the Software without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sub license, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
16 *
17 * The above copyright notice and this permission notice (including the
18 * next paragraph) shall be included in all copies or substantial portions
19 * of the Software.
20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
22 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
24 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
25 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
26 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
27 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
28 *
29 **************************************************************************/
30
31/**
32 * @file
33 * SRGB translation.
34 *
35 * @author Brian Paul <brianp@vmware.com>
36 * @author Michal Krol <michal@vmware.com>
37 * @author Jose Fonseca <jfonseca@vmware.com>
38 */
39'''
40
41
42import math
43
44
45def srgb_to_linear(x):
46    if x <= 0.04045:
47        return x / 12.92
48    else:
49        return math.pow((x + 0.055) / 1.055, 2.4)
50
51
52def linear_to_srgb(x):
53    if x >= 0.0031308:
54        return 1.055 * math.pow(x, 0.41666) - 0.055
55    else:
56        return 12.92 * x
57
58def generate_srgb_tables():
59    print 'const float'
60    print 'util_format_srgb_8unorm_to_linear_float_table[256] = {'
61    for j in range(0, 256, 4):
62        print '   ',
63        for i in range(j, j + 4):
64            print '%.7e,' % (srgb_to_linear(i / 255.0),),
65        print
66    print '};'
67    print
68    print 'const uint8_t'
69    print 'util_format_srgb_to_linear_8unorm_table[256] = {'
70    for j in range(0, 256, 16):
71        print '   ',
72        for i in range(j, j + 16):
73            print '%3u,' % (int(srgb_to_linear(i / 255.0) * 255.0 + 0.5),),
74        print
75    print '};'
76    print
77    print 'const uint8_t'
78    print 'util_format_linear_to_srgb_8unorm_table[256] = {'
79    for j in range(0, 256, 16):
80        print '   ',
81        for i in range(j, j + 16):
82            print '%3u,' % (int(linear_to_srgb(i / 255.0) * 255.0 + 0.5),),
83        print
84    print '};'
85    print
86
87
88def main():
89    print '/* This file is autogenerated by u_format_srgb.py. Do not edit directly. */'
90    print
91    # This will print the copyright message on the top of this file
92    print CopyRight.strip()
93    print
94    print '#include "u_format_srgb.h"'
95    print
96    generate_srgb_tables()
97
98
99if __name__ == '__main__':
100    main()
101