set_color - Man Page

#include <allegro.h>

void set_color(int index, const RGB *p);

Sets the specified palette entry to the specified RGB triplet. Unlike the  other palette functions this doesn't do any retrace synchronisation, so  you should call vsync() before it to prevent snow problems. Example:

   RGB rgb;
   ...
   vsync();
   set_color(192, &rgb);

set_palette(3), get_color(3), _set_color(3), ex12bit(3), exrgbhsv(3), exscroll(3)

ex12bit(3), exrgbhsv(3), exscroll(3), get_color(3), _set_color(3), set_palette(3).