New particle system

yay
But I am talking about the scene_graphnode#setLookVector method. You
already added a setLookVector in the mat4 class. What's so hard about doing
node.getWorldTransform().setLookVector(z, up)?

On Thu, Sep 25, 2014 at 10:15 PM, guycalledfrank <notifications@github.com>
wrote:

> In src/scene/scene_graphnode.js:
>
> > @@ -1078,6 +1115,37 @@ pc.extend(pc.scene, function () {
> >              }
> >          }(),
> >
>
> Modifying the world transform is hard and not all users will be able to do
> it. Just changing the Z direction is not enough, because matrix should be
> kept orthogonal. The setLookVector just makes an entity to point to a
> direction, and I had a lot of situations in my past experience when it was
> necessary. The lookAt is not easier to use when you have a vector, because
> instead of setLookVector(vec), you have to do something like
> lookAt(tempVec.copy(pos).add(vec)) which looks like crap and does redundant
> stuff (lookAt will sub your addition back and normalize the already
> normalized vector). Again, in some situations you have a vector/normal, and
> NOT the point.
>
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