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Posted by: cjstudios Mar 4 2007, 05:59 AM

if you look at the documentation under sandy.core.transform.Transform3D:

/*===========================================
combineTransform

public function combineTransform(t:Transform3D):Void

This method allows you to have a single transform3D to combine several transformations. By combining some transformations, you can expect some speed improvment since the matrix multiplication will be computed only once. BE CAREFULL, this feature can be very hard to use correctly, so you have to completely understand what you are doing. you must also take under consideration that it is the first matrix which is multiplied by the one in argument

/*===========================================

now this suggests to me that if I have a few branches of transformGroups before hitting my Object3D, the matrices for each transformGroup are multiplied together at every render cycle. is that correct?

if that is the case,
is there a way I can set the position of an object without using transform group. e.g. if my scene is static and the only moving thing is the camera. having to do matrix multiplication on every render cycle on static objects would be unnecessarily expensive wouldn't it?

I know little about 3D engine implementations and it is not my intention to criticize the wonderful job Thomas aka Kiroukou has done. I'm just curious if there's a workaround or if the observation is trivial in the first place and wouldn't significantly affect the performance.