I'm writing a 3d space game. For the movement i'm using 4x4 matrix that i use with glMultMat. I rotate in the z axis with left & right and x axis with up and down Moving my main craft has been not a problem, the problem comes when I try to make an enemy that follows me. I've tried lot of ways, but when it worked in one axis it failed in the other. ¿Does anyone know a good way for doing it or somewhere to look for code help? Thanks If you need me to post some code tell me. --------------------------- http://perso.wanadoo.es/zon7/Proyecto.rar I have uploaded a version so you can see where is the problem. In that case there are two ships. One is the one you control and the other is te "enemy". Enemy only will look where you are, no movement, only rotation. With a and z control velocity. As you will see, in the front part of the enemy everything is ok, but when you go rear all goes crazy. Thanks for your help