e14743d1 |
1 | |
2 | /* Bring up a window and manipulate the gamma on it */ |
3 | |
4 | #include <stdlib.h> |
5 | #include <stdio.h> |
6 | #include <string.h> |
7 | #include <math.h> |
8 | |
9 | #include "SDL.h" |
10 | |
11 | /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ |
12 | static void quit(int rc) |
13 | { |
14 | SDL_Quit(); |
15 | exit(rc); |
16 | } |
17 | |
18 | /* Turn a normal gamma value into an appropriate gamma ramp */ |
19 | void CalculateGamma(double gamma, Uint16 *ramp) |
20 | { |
21 | int i, value; |
22 | |
23 | gamma = 1.0 / gamma; |
24 | for ( i=0; i<256; ++i ) { |
25 | value = (int)(pow((double)i/256.0, gamma)*65535.0 + 0.5); |
26 | if ( value > 65535 ) { |
27 | value = 65535; |
28 | } |
29 | ramp[i] = (Uint16)value; |
30 | } |
31 | } |
32 | |
33 | /* This can be used as a general routine for all of the test programs */ |
34 | int get_video_args(char *argv[], int *w, int *h, int *bpp, Uint32 *flags) |
35 | { |
36 | int i; |
37 | |
38 | *w = 640; |
39 | *h = 480; |
40 | *bpp = 0; |
41 | *flags = SDL_SWSURFACE; |
42 | |
43 | for ( i=1; argv[i]; ++i ) { |
44 | if ( strcmp(argv[i], "-width") == 0 ) { |
45 | if ( argv[i+1] ) { |
46 | *w = atoi(argv[++i]); |
47 | } |
48 | } else |
49 | if ( strcmp(argv[i], "-height") == 0 ) { |
50 | if ( argv[i+1] ) { |
51 | *h = atoi(argv[++i]); |
52 | } |
53 | } else |
54 | if ( strcmp(argv[i], "-bpp") == 0 ) { |
55 | if ( argv[i+1] ) { |
56 | *bpp = atoi(argv[++i]); |
57 | } |
58 | } else |
59 | if ( strcmp(argv[i], "-fullscreen") == 0 ) { |
60 | *flags |= SDL_FULLSCREEN; |
61 | } else |
62 | if ( strcmp(argv[i], "-hw") == 0 ) { |
63 | *flags |= SDL_HWSURFACE; |
64 | } else |
65 | if ( strcmp(argv[i], "-hwpalette") == 0 ) { |
66 | *flags |= SDL_HWPALETTE; |
67 | } else |
68 | break; |
69 | } |
70 | return i; |
71 | } |
72 | |
73 | int main(int argc, char *argv[]) |
74 | { |
75 | SDL_Surface *screen; |
76 | SDL_Surface *image; |
77 | float gamma; |
78 | int i; |
79 | int w, h, bpp; |
80 | Uint32 flags; |
81 | Uint16 ramp[256]; |
82 | Uint16 red_ramp[256]; |
83 | Uint32 then, timeout; |
84 | |
85 | /* Check command line arguments */ |
86 | argv += get_video_args(argv, &w, &h, &bpp, &flags); |
87 | |
88 | /* Initialize SDL */ |
89 | if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) { |
90 | fprintf(stderr, |
91 | "Couldn't initialize SDL: %s\n", SDL_GetError()); |
92 | return(1); |
93 | } |
94 | |
95 | /* Initialize the display, always use hardware palette */ |
96 | screen = SDL_SetVideoMode(w, h, bpp, flags | SDL_HWPALETTE); |
97 | if ( screen == NULL ) { |
98 | fprintf(stderr, "Couldn't set %dx%d video mode: %s\n", |
99 | w, h, SDL_GetError()); |
100 | quit(1); |
101 | } |
102 | |
103 | /* Set the window manager title bar */ |
104 | SDL_WM_SetCaption("SDL gamma test", "testgamma"); |
105 | |
106 | /* Set the desired gamma, if any */ |
107 | gamma = 1.0f; |
108 | if ( *argv ) { |
109 | gamma = (float)atof(*argv); |
110 | } |
111 | if ( SDL_SetGamma(gamma, gamma, gamma) < 0 ) { |
112 | fprintf(stderr, "Unable to set gamma: %s\n", SDL_GetError()); |
113 | quit(1); |
114 | } |
115 | |
116 | #if 0 /* This isn't supported. Integrating the gamma ramps isn't exact */ |
117 | /* See what gamma was actually set */ |
118 | float real[3]; |
119 | if ( SDL_GetGamma(&real[0], &real[1], &real[2]) < 0 ) { |
120 | printf("Couldn't get gamma: %s\n", SDL_GetError()); |
121 | } else { |
122 | printf("Set gamma values: R=%2.2f, G=%2.2f, B=%2.2f\n", |
123 | real[0], real[1], real[2]); |
124 | } |
125 | #endif |
126 | |
127 | /* Do all the drawing work */ |
128 | image = SDL_LoadBMP("sample.bmp"); |
129 | if ( image ) { |
130 | SDL_Rect dst; |
131 | |
132 | dst.x = (screen->w - image->w)/2; |
133 | dst.y = (screen->h - image->h)/2; |
134 | dst.w = image->w; |
135 | dst.h = image->h; |
136 | SDL_BlitSurface(image, NULL, screen, &dst); |
137 | SDL_UpdateRects(screen, 1, &dst); |
138 | } |
139 | |
140 | /* Wait a bit, handling events */ |
141 | then = SDL_GetTicks(); |
142 | timeout = (5*1000); |
143 | while ( (SDL_GetTicks()-then) < timeout ) { |
144 | SDL_Event event; |
145 | |
146 | while ( SDL_PollEvent(&event) ) { |
147 | switch (event.type) { |
148 | case SDL_QUIT: /* Quit now */ |
149 | timeout = 0; |
150 | break; |
151 | case SDL_KEYDOWN: |
152 | switch (event.key.keysym.sym) { |
153 | case SDLK_SPACE: /* Go longer.. */ |
154 | timeout += (5*1000); |
155 | break; |
156 | case SDLK_UP: |
157 | gamma += 0.2f; |
158 | SDL_SetGamma(gamma, gamma, gamma); |
159 | break; |
160 | case SDLK_DOWN: |
161 | gamma -= 0.2f; |
162 | SDL_SetGamma(gamma, gamma, gamma); |
163 | break; |
164 | case SDLK_ESCAPE: |
165 | timeout = 0; |
166 | break; |
167 | default: |
168 | break; |
169 | } |
170 | break; |
171 | } |
172 | } |
173 | } |
174 | |
175 | /* Perform a gamma flash to red using color ramps */ |
176 | while ( gamma < 10.0 ) { |
177 | /* Increase the red gamma and decrease everything else... */ |
178 | gamma += 0.1f; |
179 | CalculateGamma(gamma, red_ramp); |
180 | CalculateGamma(1.0/gamma, ramp); |
181 | SDL_SetGammaRamp(red_ramp, ramp, ramp); |
182 | } |
183 | /* Finish completely red */ |
184 | memset(red_ramp, 255, sizeof(red_ramp)); |
185 | memset(ramp, 0, sizeof(ramp)); |
186 | SDL_SetGammaRamp(red_ramp, ramp, ramp); |
187 | |
188 | /* Now fade out to black */ |
189 | for ( i=(red_ramp[0] >> 8); i >= 0; --i ) { |
190 | memset(red_ramp, i, sizeof(red_ramp)); |
191 | SDL_SetGammaRamp(red_ramp, NULL, NULL); |
192 | } |
193 | SDL_Delay(1*1000); |
194 | |
195 | SDL_Quit(); |
196 | return(0); |
197 | } |