Code

void diagram_DeserializeTag(object sender, SerializeTagEventArgs e)
{
	e.Tag = new Point3D(
		e.Context.ReadFloat("X", e.Representation),
		e.Context.ReadFloat("Y", e.Representation),
		e.Context.ReadFloat("Z", e.Representation));
	e.Handled = true;
}

void diagram_SerializeTag(object sender, SerializeTagEventArgs e)
{
	Point3D point = (Point3D)e.Tag;
	e.Context.WriteFloat(point.X, "X", e.Representation);
	e.Context.WriteFloat(point.Y, "Y", e.Representation);
	e.Context.WriteFloat(point.Z, "Z", e.Representation);
	e.Handled = true;
}