e14743d1 |
1 | /* Simple program: Move N sprites around on the screen as fast as possible */ |
2 | |
3 | #include <stdio.h> |
4 | #include <stdlib.h> |
5 | #include <string.h> |
6 | #include <ctype.h> |
7 | #include <math.h> |
8 | #include <time.h> |
9 | |
10 | #include "SDL.h" |
11 | |
12 | #define NUM_SPRITES 100 |
13 | #define MAX_SPEED 1 |
14 | |
15 | SDL_Surface *sprite; |
16 | int numsprites; |
17 | SDL_Rect *sprite_rects; |
18 | SDL_Rect *positions; |
19 | SDL_Rect *velocities; |
20 | int sprites_visible; |
21 | int debug_flip; |
22 | Uint16 sprite_w, sprite_h; |
23 | |
24 | /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ |
25 | static void quit(int rc) |
26 | { |
27 | SDL_Quit(); |
28 | exit(rc); |
29 | } |
30 | |
31 | int LoadSprite(char *file) |
32 | { |
33 | SDL_Surface *temp; |
34 | |
35 | /* Load the sprite image */ |
36 | sprite = SDL_LoadBMP(file); |
37 | if ( sprite == NULL ) { |
38 | fprintf(stderr, "Couldn't load %s: %s", file, SDL_GetError()); |
39 | return(-1); |
40 | } |
41 | |
42 | /* Set transparent pixel as the pixel at (0,0) */ |
43 | if ( sprite->format->palette ) { |
44 | SDL_SetColorKey(sprite, (SDL_SRCCOLORKEY|SDL_RLEACCEL), |
45 | *(Uint8 *)sprite->pixels); |
46 | } |
47 | |
48 | /* Convert sprite to video format */ |
49 | temp = SDL_DisplayFormat(sprite); |
50 | SDL_FreeSurface(sprite); |
51 | if ( temp == NULL ) { |
52 | fprintf(stderr, "Couldn't convert background: %s\n", |
53 | SDL_GetError()); |
54 | return(-1); |
55 | } |
56 | sprite = temp; |
57 | |
58 | /* We're ready to roll. :) */ |
59 | return(0); |
60 | } |
61 | |
62 | void MoveSprites(SDL_Surface *screen, Uint32 background) |
63 | { |
64 | int i, nupdates; |
65 | SDL_Rect area, *position, *velocity; |
66 | |
67 | nupdates = 0; |
68 | /* Erase all the sprites if necessary */ |
69 | if ( sprites_visible ) { |
70 | SDL_FillRect(screen, NULL, background); |
71 | } |
72 | |
73 | /* Move the sprite, bounce at the wall, and draw */ |
74 | for ( i=0; i<numsprites; ++i ) { |
75 | position = &positions[i]; |
76 | velocity = &velocities[i]; |
77 | position->x += velocity->x; |
78 | if ( (position->x < 0) || (position->x >= (screen->w - sprite_w)) ) { |
79 | velocity->x = -velocity->x; |
80 | position->x += velocity->x; |
81 | } |
82 | position->y += velocity->y; |
83 | if ( (position->y < 0) || (position->y >= (screen->h - sprite_w)) ) { |
84 | velocity->y = -velocity->y; |
85 | position->y += velocity->y; |
86 | } |
87 | |
88 | /* Blit the sprite onto the screen */ |
89 | area = *position; |
90 | SDL_BlitSurface(sprite, NULL, screen, &area); |
91 | sprite_rects[nupdates++] = area; |
92 | } |
93 | |
94 | if (debug_flip) { |
95 | if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { |
96 | static int t = 0; |
97 | |
98 | Uint32 color = SDL_MapRGB (screen->format, 255, 0, 0); |
99 | SDL_Rect r; |
100 | r.x = (sin((float)t * 2 * 3.1459) + 1.0) / 2.0 * (screen->w-20); |
101 | r.y = 0; |
102 | r.w = 20; |
103 | r.h = screen->h; |
104 | |
105 | SDL_FillRect (screen, &r, color); |
106 | t+=2; |
107 | } |
108 | } |
109 | |
110 | /* Update the screen! */ |
111 | if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { |
112 | SDL_Flip(screen); |
113 | } else { |
114 | SDL_UpdateRects(screen, nupdates, sprite_rects); |
115 | } |
116 | sprites_visible = 1; |
117 | } |
118 | |
119 | /* This is a way of telling whether or not to use hardware surfaces */ |
120 | Uint32 FastestFlags(Uint32 flags, int width, int height, int bpp) |
121 | { |
122 | const SDL_VideoInfo *info; |
123 | |
124 | /* Hardware acceleration is only used in fullscreen mode */ |
125 | flags |= SDL_FULLSCREEN; |
126 | |
127 | /* Check for various video capabilities */ |
128 | info = SDL_GetVideoInfo(); |
129 | if ( info->blit_hw_CC && info->blit_fill ) { |
130 | /* We use accelerated colorkeying and color filling */ |
131 | flags |= SDL_HWSURFACE; |
132 | } |
133 | /* If we have enough video memory, and will use accelerated |
134 | blits directly to it, then use page flipping. |
135 | */ |
136 | if ( (flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { |
137 | /* Direct hardware blitting without double-buffering |
138 | causes really bad flickering. |
139 | */ |
140 | if ( info->video_mem*1024 > (height*width*bpp/8) ) { |
141 | flags |= SDL_DOUBLEBUF; |
142 | } else { |
143 | flags &= ~SDL_HWSURFACE; |
144 | } |
145 | } |
146 | |
147 | /* Return the flags */ |
148 | return(flags); |
149 | } |
150 | |
151 | int main(int argc, char *argv[]) |
152 | { |
153 | SDL_Surface *screen; |
154 | Uint8 *mem; |
155 | int width, height; |
156 | Uint8 video_bpp; |
157 | Uint32 videoflags; |
158 | Uint32 background; |
159 | int i, done; |
160 | SDL_Event event; |
161 | Uint32 then, now, frames; |
162 | |
163 | /* Initialize SDL */ |
164 | if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) { |
165 | fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError()); |
166 | return(1); |
167 | } |
168 | |
169 | numsprites = NUM_SPRITES; |
170 | videoflags = SDL_SWSURFACE|SDL_ANYFORMAT; |
171 | width = 640; |
172 | height = 480; |
173 | video_bpp = 8; |
174 | debug_flip = 0; |
175 | while ( argc > 1 ) { |
176 | --argc; |
177 | if ( strcmp(argv[argc-1], "-width") == 0 ) { |
178 | width = atoi(argv[argc]); |
179 | --argc; |
180 | } else |
181 | if ( strcmp(argv[argc-1], "-height") == 0 ) { |
182 | height = atoi(argv[argc]); |
183 | --argc; |
184 | } else |
185 | if ( strcmp(argv[argc-1], "-bpp") == 0 ) { |
186 | video_bpp = atoi(argv[argc]); |
187 | videoflags &= ~SDL_ANYFORMAT; |
188 | --argc; |
189 | } else |
190 | if ( strcmp(argv[argc], "-fast") == 0 ) { |
191 | videoflags = FastestFlags(videoflags, width, height, video_bpp); |
192 | } else |
193 | if ( strcmp(argv[argc], "-hw") == 0 ) { |
194 | videoflags ^= SDL_HWSURFACE; |
195 | } else |
196 | if ( strcmp(argv[argc], "-flip") == 0 ) { |
197 | videoflags ^= SDL_DOUBLEBUF; |
198 | } else |
199 | if ( strcmp(argv[argc], "-debugflip") == 0 ) { |
200 | debug_flip ^= 1; |
201 | } else |
202 | if ( strcmp(argv[argc], "-fullscreen") == 0 ) { |
203 | videoflags ^= SDL_FULLSCREEN; |
204 | } else |
205 | if ( isdigit(argv[argc][0]) ) { |
206 | numsprites = atoi(argv[argc]); |
207 | } else { |
208 | fprintf(stderr, |
209 | "Usage: %s [-bpp N] [-hw] [-flip] [-fast] [-fullscreen] [numsprites]\n", |
210 | argv[0]); |
211 | quit(1); |
212 | } |
213 | } |
214 | |
215 | /* Set video mode */ |
216 | screen = SDL_SetVideoMode(width, height, video_bpp, videoflags); |
217 | if ( ! screen ) { |
218 | fprintf(stderr, "Couldn't set %dx%d video mode: %s\n", |
219 | width, height, SDL_GetError()); |
220 | quit(2); |
221 | } |
222 | |
223 | /* Load the sprite */ |
224 | if ( LoadSprite("icon.bmp") < 0 ) { |
225 | quit(1); |
226 | } |
227 | |
228 | /* Allocate memory for the sprite info */ |
229 | mem = (Uint8 *)malloc(4*sizeof(SDL_Rect)*numsprites); |
230 | if ( mem == NULL ) { |
231 | SDL_FreeSurface(sprite); |
232 | fprintf(stderr, "Out of memory!\n"); |
233 | quit(2); |
234 | } |
235 | sprite_rects = (SDL_Rect *)mem; |
236 | positions = sprite_rects; |
237 | sprite_rects += numsprites; |
238 | velocities = sprite_rects; |
239 | sprite_rects += numsprites; |
240 | sprite_w = sprite->w; |
241 | sprite_h = sprite->h; |
242 | srand(time(NULL)); |
243 | for ( i=0; i<numsprites; ++i ) { |
244 | positions[i].x = rand()%(screen->w - sprite_w); |
245 | positions[i].y = rand()%(screen->h - sprite_h); |
246 | positions[i].w = sprite->w; |
247 | positions[i].h = sprite->h; |
248 | velocities[i].x = 0; |
249 | velocities[i].y = 0; |
250 | while ( ! velocities[i].x && ! velocities[i].y ) { |
251 | velocities[i].x = (rand()%(MAX_SPEED*2+1))-MAX_SPEED; |
252 | velocities[i].y = (rand()%(MAX_SPEED*2+1))-MAX_SPEED; |
253 | } |
254 | } |
255 | background = SDL_MapRGB(screen->format, 0x00, 0x00, 0x00); |
256 | |
257 | /* Print out information about our surfaces */ |
258 | printf("Screen is at %d bits per pixel\n",screen->format->BitsPerPixel); |
259 | if ( (screen->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { |
260 | printf("Screen is in video memory\n"); |
261 | } else { |
262 | printf("Screen is in system memory\n"); |
263 | } |
264 | if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { |
265 | printf("Screen has double-buffering enabled\n"); |
266 | } |
267 | if ( (sprite->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { |
268 | printf("Sprite is in video memory\n"); |
269 | } else { |
270 | printf("Sprite is in system memory\n"); |
271 | } |
272 | /* Run a sample blit to trigger blit acceleration */ |
273 | { SDL_Rect dst; |
274 | dst.x = 0; |
275 | dst.y = 0; |
276 | dst.w = sprite->w; |
277 | dst.h = sprite->h; |
278 | SDL_BlitSurface(sprite, NULL, screen, &dst); |
279 | SDL_FillRect(screen, &dst, background); |
280 | } |
281 | if ( (sprite->flags & SDL_HWACCEL) == SDL_HWACCEL ) { |
282 | printf("Sprite blit uses hardware acceleration\n"); |
283 | } |
284 | if ( (sprite->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { |
285 | printf("Sprite blit uses RLE acceleration\n"); |
286 | } |
287 | |
288 | /* Loop, blitting sprites and waiting for a keystroke */ |
289 | frames = 0; |
290 | then = SDL_GetTicks(); |
291 | done = 0; |
292 | sprites_visible = 0; |
293 | while ( !done ) { |
294 | /* Check for events */ |
295 | ++frames; |
296 | while ( SDL_PollEvent(&event) ) { |
297 | switch (event.type) { |
298 | case SDL_MOUSEBUTTONDOWN: |
299 | SDL_WarpMouse(screen->w/2, screen->h/2); |
300 | break; |
301 | case SDL_KEYDOWN: |
302 | /* Any keypress quits the app... */ |
303 | case SDL_QUIT: |
304 | done = 1; |
305 | break; |
306 | default: |
307 | break; |
308 | } |
309 | } |
310 | MoveSprites(screen, background); |
311 | } |
312 | SDL_FreeSurface(sprite); |
313 | free(mem); |
314 | |
315 | /* Print out some timing information */ |
316 | now = SDL_GetTicks(); |
317 | if ( now > then ) { |
318 | printf("%2.2f frames per second\n", |
319 | ((double)frames*1000)/(now-then)); |
320 | } |
321 | SDL_Quit(); |
322 | return(0); |
323 | } |