SDL_x11gamma.c
1
2
/*
SDL - Simple DirectMedia Layer
3
Copyright (C) 1997-2012 Sam Lantinga
4
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Lesser General Public
7
License as published by the Free Software Foundation; either
8
version 2.1 of the License, or (at your option) any later version.
9
10
11
12
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
13
Lesser General Public License for more details.
15
16
17
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19
Sam Lantinga
20
slouken@libsdl.org
21
*/
22
#include "SDL_config.h"
23
24
25
#include "SDL.h"
#include "SDL_events.h"
26
#include "../../events/SDL_events_c.h"
27
28
29
30
31
32
33
34
#include "SDL_x11video.h"
/* From the X server sources... */
#define MAX_GAMMA 10.0
#define MIN_GAMMA (1.0/MAX_GAMMA)
static int X11_SetGammaNoLock(_THIS, float red, float green, float blue)
{
35
#if SDL_VIDEO_DRIVER_X11_VIDMODE
36
if (use_vidmode >= 200) {
37
SDL_NAME(XF86VidModeGamma) gamma;
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
Bool succeeded;
/* Clamp the gamma values */
if ( red < MIN_GAMMA ) {
gamma.red = MIN_GAMMA;
} else
if ( red > MAX_GAMMA ) {
gamma.red = MAX_GAMMA;
} else {
gamma.red = red;
}
if ( green < MIN_GAMMA ) {
gamma.green = MIN_GAMMA;
} else
if ( green > MAX_GAMMA ) {
gamma.green = MAX_GAMMA;
} else {
gamma.green = green;
}
if ( blue < MIN_GAMMA ) {
gamma.blue = MIN_GAMMA;
} else
if ( blue > MAX_GAMMA ) {
gamma.blue = MAX_GAMMA;
} else {
gamma.blue = blue;
}
if ( SDL_GetAppState() & SDL_APPACTIVE ) {
66
succeeded = SDL_NAME(XF86VidModeSetGamma)(SDL_Display, SDL_Screen, &gamma);
67
XSync(SDL_Display, False);
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
} else {
gamma_saved[0] = gamma.red;
gamma_saved[1] = gamma.green;
gamma_saved[2] = gamma.blue;
succeeded = True;
}
if ( succeeded ) {
++gamma_changed;
}
return succeeded ? 0 : -1;
}
#endif
SDL_SetError("Gamma correction not supported");
return -1;
}
int X11_SetVidModeGamma(_THIS, float red, float green, float blue)
{
int result;
SDL_Lock_EventThread();
result = X11_SetGammaNoLock(this, red, green, blue);
SDL_Unlock_EventThread();
return(result);
}
static int X11_GetGammaNoLock(_THIS, float *red, float *green, float *blue)
{
96
#if SDL_VIDEO_DRIVER_X11_VIDMODE
97
if (use_vidmode >= 200) {
98
99
SDL_NAME(XF86VidModeGamma) gamma;
if (SDL_NAME(XF86VidModeGetGamma)(SDL_Display, SDL_Screen, &gamma)) {
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
*red = gamma.red;
*green = gamma.green;
*blue = gamma.blue;
return 0;
}
return -1;
}
#endif
return -1;
}
int X11_GetVidModeGamma(_THIS, float *red, float *green, float *blue)
{
int result;
SDL_Lock_EventThread();
result = X11_GetGammaNoLock(this, red, green, blue);
SDL_Unlock_EventThread();
return(result);
}
void X11_SaveVidModeGamma(_THIS)
{
/* Try to save the current gamma, otherwise disable gamma control */
if ( X11_GetGammaNoLock(this,
&gamma_saved[0], &gamma_saved[1], &gamma_saved[2]) < 0 ) {
this->SetGamma = 0;
this->GetGamma = 0;
}
gamma_changed = 0;
}
void X11_SwapVidModeGamma(_THIS)
{
float new_gamma[3];
if ( gamma_changed ) {
new_gamma[0] = gamma_saved[0];
new_gamma[1] = gamma_saved[1];
new_gamma[2] = gamma_saved[2];
X11_GetGammaNoLock(this, &gamma_saved[0], &gamma_saved[1], &gamma_saved[2]);
X11_SetGammaNoLock(this, new_gamma[0], new_gamma[1], new_gamma[2]);
}
}