Matrix4x4_Invert_Full(&mat, viewmatrix);
Matrix4x4_FromVectors(viewmatrix, forward, left, up, origin);
Matrix4x4_Concat(&matq, viewmatrix, &mat);
Matrix4x4_Invert_Full(&mat, viewmatrix);
Matrix4x4_FromVectors(viewmatrix, forward, left, up, origin);
Matrix4x4_Concat(&matq, viewmatrix, &mat);