1/* 2 SDL - Simple DirectMedia Layer 3 Copyright (C) 1997-2006 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 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with this library; if not, write to the Free Software 17 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#include "SDL.h" 25#include "SDL_events.h" 26#include "../../events/SDL_events_c.h" 27#include "SDL_x11video.h" 28 29/* From the X server sources... */ 30#define MAX_GAMMA 10.0 31#define MIN_GAMMA (1.0/MAX_GAMMA) 32 33static int X11_SetGammaNoLock(_THIS, float red, float green, float blue) 34{ 35#if SDL_VIDEO_DRIVER_X11_VIDMODE 36 if (use_vidmode >= 200) { 37 SDL_NAME(XF86VidModeGamma) gamma; 38 Bool succeeded; 39 40 /* Clamp the gamma values */ 41 if ( red < MIN_GAMMA ) { 42 gamma.red = MIN_GAMMA; 43 } else 44 if ( red > MAX_GAMMA ) { 45 gamma.red = MAX_GAMMA; 46 } else { 47 gamma.red = red; 48 } 49 if ( green < MIN_GAMMA ) { 50 gamma.green = MIN_GAMMA; 51 } else 52 if ( green > MAX_GAMMA ) { 53 gamma.green = MAX_GAMMA; 54 } else { 55 gamma.green = green; 56 } 57 if ( blue < MIN_GAMMA ) { 58 gamma.blue = MIN_GAMMA; 59 } else 60 if ( blue > MAX_GAMMA ) { 61 gamma.blue = MAX_GAMMA; 62 } else { 63 gamma.blue = blue; 64 } 65 if ( SDL_GetAppState() & SDL_APPACTIVE ) { 66 succeeded = SDL_NAME(XF86VidModeSetGamma)(SDL_Display, SDL_Screen, &gamma); 67 XSync(SDL_Display, False); 68 } else { 69 gamma_saved[0] = gamma.red; 70 gamma_saved[1] = gamma.green; 71 gamma_saved[2] = gamma.blue; 72 succeeded = True; 73 } 74 if ( succeeded ) { 75 ++gamma_changed; 76 } 77 return succeeded ? 0 : -1; 78 } 79#endif 80 SDL_SetError("Gamma correction not supported"); 81 return -1; 82} 83int X11_SetVidModeGamma(_THIS, float red, float green, float blue) 84{ 85 int result; 86 87 SDL_Lock_EventThread(); 88 result = X11_SetGammaNoLock(this, red, green, blue); 89 SDL_Unlock_EventThread(); 90 91 return(result); 92} 93 94static int X11_GetGammaNoLock(_THIS, float *red, float *green, float *blue) 95{ 96#if SDL_VIDEO_DRIVER_X11_VIDMODE 97 if (use_vidmode >= 200) { 98 SDL_NAME(XF86VidModeGamma) gamma; 99 if (SDL_NAME(XF86VidModeGetGamma)(SDL_Display, SDL_Screen, &gamma)) { 100 *red = gamma.red; 101 *green = gamma.green; 102 *blue = gamma.blue; 103 return 0; 104 } 105 return -1; 106 } 107#endif 108 return -1; 109} 110int X11_GetVidModeGamma(_THIS, float *red, float *green, float *blue) 111{ 112 int result; 113 114 SDL_Lock_EventThread(); 115 result = X11_GetGammaNoLock(this, red, green, blue); 116 SDL_Unlock_EventThread(); 117 118 return(result); 119} 120 121void X11_SaveVidModeGamma(_THIS) 122{ 123 /* Try to save the current gamma, otherwise disable gamma control */ 124 if ( X11_GetGammaNoLock(this, 125 &gamma_saved[0], &gamma_saved[1], &gamma_saved[2]) < 0 ) { 126 this->SetGamma = 0; 127 this->GetGamma = 0; 128 } 129 gamma_changed = 0; 130} 131void X11_SwapVidModeGamma(_THIS) 132{ 133 float new_gamma[3]; 134 135 if ( gamma_changed ) { 136 new_gamma[0] = gamma_saved[0]; 137 new_gamma[1] = gamma_saved[1]; 138 new_gamma[2] = gamma_saved[2]; 139 X11_GetGammaNoLock(this, &gamma_saved[0], &gamma_saved[1], &gamma_saved[2]); 140 X11_SetGammaNoLock(this, new_gamma[0], new_gamma[1], new_gamma[2]); 141 } 142} 143