As per your second question, lets say you have vx and vy as the velocities of the rocket in the x and y directions. Then you have speed as the speed at which the rocket will travel. You can use the following code.
(x1,y1 and x2,y2 are the start/end points)
(x1,y1 and x2,y2 are the start/end points)
local dx = x1-x2 local dy = y1-y2 local mag# = sqr(dx^2+dy^2) vx = dx*speed/mag vy = dy*speed/mag