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/*
* Example program for the Allegro library, by Shawn Hargreaves.
*
* This program shows how to specify colors in the various different
* truecolor pixel formats.
*/
#include "allegro.h"
void test(int colordepth)
{
PALETTE pal;
int x;
/* set the screen mode */
set_color_depth(colordepth);
if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0)
return;
/* in case this is a 256 color mode, we'd better make sure that the
* palette is set to something sensible. This function generates a
* standard palette with a nice range of different colors...
*/
generate_332_palette(pal);
set_palette(pal);
acquire_screen();
clear_to_color(screen, makecol(0, 0, 0));
text_mode(-1);
textprintf(screen, font, 0, 0, makecol(255, 255, 255), "%d bit color...", colordepth);
/* use the makecol() function to specify RGB values... */
textout(screen, font, "Red", 32, 80, makecol(255, 0, 0 ));
textout(screen, font, "Green", 32, 100, makecol(0, 255, 0 ));
textout(screen, font, "Blue", 32, 120, makecol(0, 0, 255));
textout(screen, font, "Yellow", 32, 140, makecol(255, 255, 0 ));
textout(screen, font, "Cyan", 32, 160, makecol(0, 255, 255));
textout(screen, font, "Magenta", 32, 180, makecol(255, 0, 255));
textout(screen, font, "Grey", 32, 200, makecol(128, 128, 128));
/* or we could draw some nice smooth color gradients... */
for (x=0; x<256; x++) {
vline(screen, 192+x, 112, 176, makecol(x, 0, 0));
vline(screen, 192+x, 208, 272, makecol(0, x, 0));
vline(screen, 192+x, 304, 368, makecol(0, 0, x));
}
textout_centre(screen, font, "<press a key>", SCREEN_W/2, SCREEN_H-16, makecol(255, 255, 255));
release_screen();
readkey();
}
int main()
{
allegro_init();
install_keyboard();
/* try each of the possible possible color depths... */
test(8);
test(15);
test(16);
test(24);
test(32);
return 0;
}
END_OF_MAIN();
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