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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. */
quit(int rc)12 static void quit(int rc)
13 {
14 	SDL_Quit();
15 	exit(rc);
16 }
17 
LoadXBM(SDL_Surface * screen,int w,int h,Uint8 * bits)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 
main(int argc,char * argv[])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 }
185