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/*
* Example program for the Allegro library, by Shawn Hargreaves.
*
* This program demonstrates how to load and display bitmap files
* in truecolor video modes, and how to crossfade between them.
*/
#include "allegro.h"
int show(char *name)
{
BITMAP *bmp, *buffer;
PALETTE pal;
int alpha;
/* load the file */
bmp = load_bitmap(name, pal);
if (!bmp)
return -1;
buffer = create_bitmap(SCREEN_W, SCREEN_H);
blit(screen, buffer, 0, 0, 0, 0, SCREEN_W, SCREEN_H);
set_palette(pal);
/* fade it in on top of the previous picture */
for (alpha=0; alpha<256; alpha+=8) {
set_trans_blender(0, 0, 0, alpha);
draw_trans_sprite(buffer, bmp, (SCREEN_W-bmp->w)/2, (SCREEN_H-bmp->h)/2);
vsync();
blit(buffer, screen, 0, 0, 0, 0, SCREEN_W, SCREEN_H);
if (keypressed()) {
destroy_bitmap(bmp);
destroy_bitmap(buffer);
if ((readkey() & 0xFF) == 27)
return 1;
else
return 0;
}
}
blit(bmp, screen, 0, 0, (SCREEN_W-bmp->w)/2, (SCREEN_H-bmp->h)/2, bmp->w, bmp->h);
destroy_bitmap(bmp);
destroy_bitmap(buffer);
if ((readkey() & 0xFF) == 27)
return 1;
else
return 0;
}
int main(int argc, char *argv[])
{
int i;
allegro_init();
if (argc < 2) {
allegro_message("Usage: 'exxfade files.[bmp|lbm|pcx|tga]'\n");
return 1;
}
install_keyboard();
/* set the best color depth that we can find */
set_color_depth(16);
if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
set_color_depth(15);
if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
set_color_depth(32);
if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
set_color_depth(24);
if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Error setting graphics mode\n%s\n", allegro_error);
return 1;
}
}
}
}
/* load all images in the same color depth as the display */
set_color_conversion(COLORCONV_TOTAL);
/* process all the files on our command line */
for (i=1; i<argc; i++) {
switch (show(argv[i])) {
case -1:
/* error */
set_gfx_mode(GFX_TEXT, 0, 0, 0, 0);
allegro_message("Error loading image file '%s'\n", argv[i]);
return 1;
case 0:
/* ok! */
break;
case 1:
/* quit */
allegro_exit();
return 0;
}
}
return 0;
}
END_OF_MAIN();
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