1 

     2 /* Simple program:  Test bitmap blits */

     3 

     4 #include <stdio.h>

     5 #include <stdlib.h>

     6 #include <string.h>

     7 

     8 #include "SDL.h"

     9 #include "picture.xbm"

    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 SDL_Surface *LoadXBM(SDL_Surface *screen, int w, int h, Uint8 *bits)

    19 {

    20 	SDL_Surface *bitmap;

    21 	Uint8 *line;

    22 

    23 	/* Allocate the bitmap */

    24 	bitmap = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 1, 0, 0, 0, 0);

    25 	if ( bitmap == NULL ) {

    26 		fprintf(stderr, "Couldn't allocate bitmap: %s\n",

    27 						SDL_GetError());

    28 		return(NULL);

    29 	}

    30 

    31 	/* Copy the pixels */

    32 	line = (Uint8 *)bitmap->pixels;

    33 	w = (w+7)/8;

    34 	while ( h-- ) {

    35 		memcpy(line, bits, w);

    36 		/* X11 Bitmap images have the bits reversed */

    37 		{ int i, j; Uint8 *buf, byte;

    38 			for ( buf=line, i=0; i<w; ++i, ++buf ) {

    39 				byte = *buf;

    40 				*buf = 0;

    41 				for ( j=7; j>=0; --j ) {

    42 					*buf |= (byte&0x01)<<j;

    43 					byte >>= 1;

    44 				}

    45 			}

    46 		}

    47 		line += bitmap->pitch;

    48 		bits += w;

    49 	}

    50 	return(bitmap);

    51 }

    52 

    53 int main(int argc, char *argv[])

    54 {

    55 	SDL_Surface *screen;

    56 	SDL_Surface *bitmap;

    57 	Uint8  video_bpp;

    58 	Uint32 videoflags;

    59 	Uint8 *buffer;

    60 	int i, k, done;

    61 	SDL_Event event;

    62 	Uint16 *buffer16;

    63         Uint16 color;

    64         Uint8  gradient;

    65 	SDL_Color palette[256];

    66 

    67 

    68 	/* Initialize SDL */

    69 	if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {

    70 		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());

    71 		return(1);

    72 	}

    73 

    74 	video_bpp = 0;

    75 	videoflags = SDL_SWSURFACE;

    76 	while ( argc > 1 ) {

    77 		--argc;

    78 		if ( strcmp(argv[argc-1], "-bpp") == 0 ) {

    79 			video_bpp = atoi(argv[argc]);

    80 			--argc;

    81 		} else

    82 		if ( strcmp(argv[argc], "-warp") == 0 ) {

    83 			videoflags |= SDL_HWPALETTE;

    84 		} else

    85 		if ( strcmp(argv[argc], "-hw") == 0 ) {

    86 			videoflags |= SDL_HWSURFACE;

    87 		} else

    88 		if ( strcmp(argv[argc], "-fullscreen") == 0 ) {

    89 			videoflags |= SDL_FULLSCREEN;

    90 		} else {

    91 			fprintf(stderr,

    92 			"Usage: %s [-bpp N] [-warp] [-hw] [-fullscreen]\n",

    93 								argv[0]);

    94 			quit(1);

    95 		}

    96 	}

    97 

    98 	/* Set 640x480 video mode */

    99 	if ( (screen=SDL_SetVideoMode(640,480,video_bpp,videoflags)) == NULL ) {

   100 		fprintf(stderr, "Couldn't set 640x480x%d video mode: %s\n",

   101 						video_bpp, SDL_GetError());

   102 		quit(2);

   103 	}

   104 

   105 	if (video_bpp==8) {

   106 		/* Set a gray colormap, reverse order from white to black */

   107 		for ( i=0; i<256; ++i ) {

   108 			palette[i].r = 255-i;

   109 			palette[i].g = 255-i;

   110 			palette[i].b = 255-i;

   111 		}

   112 		SDL_SetColors(screen, palette, 0, 256);

   113 	}

   114 

   115 	/* Set the surface pixels and refresh! */

   116 	if ( SDL_LockSurface(screen) < 0 ) {

   117 		fprintf(stderr, "Couldn't lock the display surface: %s\n",

   118 							SDL_GetError());

   119 		quit(2);

   120 	}

   121 	buffer=(Uint8 *)screen->pixels;

   122 	if (screen->format->BytesPerPixel!=2) {

   123         	for ( i=0; i<screen->h; ++i ) {

   124         		memset(buffer,(i*255)/screen->h, screen->pitch);

   125         		buffer += screen->pitch;

   126         	}

   127         }

   128         else

   129         {

   130 		for ( i=0; i<screen->h; ++i ) {

   131 			gradient=((i*255)/screen->h);

   132                         color = SDL_MapRGB(screen->format, gradient, gradient, gradient);

   133                         buffer16=(Uint16*)buffer;

   134                         for (k=0; k<screen->w; k++)

   135                         {

   136                             *(buffer16+k)=color;

   137                         }

   138 			buffer += screen->pitch;

   139 		}

   140         }

   141 	SDL_UnlockSurface(screen);

   142 	SDL_UpdateRect(screen, 0, 0, 0, 0);

   143 

   144 	/* Load the bitmap */

   145 	bitmap = LoadXBM(screen, picture_width, picture_height,

   146 					(Uint8 *)picture_bits);

   147 	if ( bitmap == NULL ) {

   148 		quit(1);

   149 	}

   150 

   151 	/* Wait for a keystroke */

   152 	done = 0;

   153 	while ( !done ) {

   154 		/* Check for events */

   155 		while ( SDL_PollEvent(&event) ) {

   156 			switch (event.type) {

   157 				case SDL_MOUSEBUTTONDOWN: {

   158 					SDL_Rect dst;

   159 

   160 					dst.x = event.button.x - bitmap->w/2;

   161 					dst.y = event.button.y - bitmap->h/2;

   162 					dst.w = bitmap->w;

   163 					dst.h = bitmap->h;

   164 					SDL_BlitSurface(bitmap, NULL,

   165 								screen, &dst);

   166 					SDL_UpdateRects(screen,1,&dst);

   167 					}

   168 					break;

   169 				case SDL_KEYDOWN:

   170 					/* Any key press quits the app... */

   171 					done = 1;

   172 					break;

   173 				case SDL_QUIT:

   174 					done = 1;

   175 					break;

   176 				default:

   177 					break;

   178 			}

   179 		}

   180 	}

   181 	SDL_FreeSurface(bitmap);

   182 	SDL_Quit();

   183 	return(0);

   184 }