draw_pixel
draw_pixel(fbi, x, y, 0xffffff);
draw_pixel(fbi, x, y, 0xff);
draw_pixel(fbi, x, y, 0xff00);
draw_pixel(fbi, x, y, 0xff0000);
draw_pixel(fbi, x, y, 0xffff00);
draw_pixel(fbi, x, y, 0xffffff);
draw_pixel(fbi, x, y, 0xff00ff);
draw_pixel(fbi, x, y, 0x00ffff);
draw_pixel(fbi, x, y, c);
draw_pixel(fbi, x, y, 0);