Hey guys, I wasn''t sure whether I should of posted this in here, or in the Maths and Physics forum, but this should do. I have a function that returns a 4*4 Matrix froma Quaternion (I think it''s a common matrix, out the on must tutorials and stuff). I normally just use it with glMultMatrixf(matrix); However, I also want to rotate a vector by this matrix without using iany gl functions, and I was just wondering on the procedure when I multiply the vector [x,y,z] by this rotation, as OpenGL itself stores it''s matricies rotated, so I don''t knwo whether it''d be normal matrix multiplication. Does this make any sense? Thanks in advance for any help.