public static VertexStore RotateRadToNewVxs(this VertexStore src, double rad, VertexStore outputVxs)
{
return(AffineMat.GetRotateMat(rad).TransformToVxs(src, outputVxs));
//Affine aff = Affine.NewRotation(rad);
//return aff.TransformToVxs(src, outputVxs);
}