matrices ?

Hello! I am wondering if there is any "default" value that I can set my matrices to? Something like the common "NULL". something like this: matRotX = NULL; //something like that Well, while I'm at it. If I would like to set the value of my World matrix to one of my Rotation matrices, how would I do that? (my world matrice has gotten no value yet, so I can only put it as the Result matix in the MatrixMultiply() call) something like this: marWorld = matRotX; //something like that One more thing... Do the MatrixMultiply() and MatrixTranslation() calls slow my app down very much or am I only to worry about the SetTransform() calls?? thx! [edited by - bilsa on May 7, 2003 10:56:01 AM] [edited by - bilsa on May 7, 2003 10:56:30 AM] [edited by - bilsa on May 7, 2003 10:59:47 AM]