Thanks, I have tried to implement your suggestions into my code. However I didn't have much success in doing so.

Standing on a plane the turret is still working fine.
But when its angles are changed (e.g. tilt or roll) it aims at a wrong location.

Nevertheless I think this is the right approach.

This is the code:

Code:

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define barrel_handle, skill1;

action ent_turret
{
	my.barrel_handle = handle(ent_create("turret_barrel.mdl", my.x, NULL));
	
	while(my) {
		
		you = ptr_for_handle(my.barrel_handle);
		
		var  vec_to_ent[3];
		var  ang_to_ent[3];

                vec_diff(vec_to_ent, camera.x, my.x); // direction vector
		
		vec_set(temp, my.pan);         // Store the angle in temp
                vec_inverse(temp);             // Invert the angle
                vec_rotate(vec_to_ent, temp);  // Rotate the vector
      
		vec_to_angle(ang_to_ent, vec_to_ent); // angle of direction vector

		// first rotate the turret's body
		ang_rotate(my.pan, vector(ang_to_ent.pan,0,0));
		
                // now rotate the barrel
		vec_set(you.pan, my.pan);
		ang_rotate(you.pan, vector(0,ang_to_ent.tilt,0));
		
		
		
		wait(1);	
	}	
}

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