int tx, ty;
for(pos.x = start_x, tx = tsx; pos.x < end_x; pos.x += 32, ++tx) {
for(pos.y = start_y, ty = tsy; pos.y < end_y; pos.y += 32, ++ty) {
int tx, ty;
for(pos.x = start_x, tx = tsx; pos.x < end_x; pos.x += 32, ++tx) {
for(pos.y = start_y, ty = tsy; pos.y < end_y; pos.y += 32, ++ty) {