#define square_width 16
#define square_height 16
static unsigned char square_bits[] = {
   0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0f, 0xf0, 0x0f, 0xf0,
   0x0f, 0xf0, 0x0f, 0xf0, 0x0f, 0xf0, 0x0f, 0xf0, 0x0f, 0xf0, 0x0f, 0xf0,
   0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};