hello. I'm creating an ifc importer. I'm creating some simple beam with rotation about X , about Y and about Z. These are the matrixes that i get: 1)Rotation about Z 0.8|0.5|0.0 0.0|0.0|1.0 -0.5|0.8|0.0 i know that the real rotation about Z is : 0.8|0.5|0.0 -0.5|0.8|0.0 0.0|0.0|1.0 then i must swap the axis y with z 1)Rotation about X 0.0|0.8|0.5 1.0|0.0|0.0 0.0|-0.5|0.8 i know that the real rotation about X is : 1.0|0.0|0.0 0.0|0.8|0.5 0.0|0.5|0.8 then i must swap the axis y with x 1)Rotation about Y 0.8|0.0|0.5 0.0|1.0|0.0 0.8|0.0|0.8 that is a correct Y rotation matrix. Exist a matrix that multiplied for the Z matrix rotation swap the y axis with the z axis and that multiplied for the X matrix rotation swap the y axis and the x axis? thanks.