test/testsprite.c
author Ryan C. Gordon <icculus@icculus.org>
Wed, 28 Sep 2005 11:36:20 +0000
changeset 1151 be9c9c8f6d53
parent 753 b14fdadd8311
child 1214 31103dbf1c26
permissions -rw-r--r--
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
if SDL is built with a non-cdecl calling convention, and it's just generally
bad practice anyhow.

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