New particle system

yay
You select codeblocks to comment in a bit strange way - they not point to things you discuss sometimes. If you're talking about setLookVector, it sets the Z direction of the matrix. Originally you had lookAt function, but it accepts a target position and internally computes (target - pos).normalize vector. But sometimes you already have a vector (e.g. picked normal from physics engine) and you don't want to perform unnecessary computations.