void amarker(){

	VECTOR* to = vector(0,0,0);
	VECTOR* from = vector(0,0,0);
	
	set(my,PASSABLE);
	while(1){
		from = vec_for_screen(mouse_cursor,camera);	
		from.z = camera.z;
		vec_set(to,from);
		to.z -=500;
		c_trace(from,to,IGNORE_ME|IGNORE_PASSABLE);
		vec_set(my.x,target);
		wait(1);
	}
}