[away3d] What is the difference between Sprite2D and Sprite2DDir

[SasMaster]

Hello Guys , I would like to get info about differences  between
Sprite2D and Sprite2DDir .
In these days I am preparing to a Lecture where I am going to be a
speaker about all the Flash Platform based 3D engines , and because
AWAy3D is my favorite (most of 3D stuff  in my Company was made with
it) , so I am going to talk about Away3D and I believe also , then
more people will start working with this awesome Framework.  The Event
will be held in Tel-Aviv University ,Israel , January 28 .