Offset inter = pt + d * get_normal ((th/2) * pt.direction ());
pango_matrix_transform_point (&trans, &inter[X_AXIS], &inter[Y_AXIS]);
points[d].push_back (inter);
Offset inter = pt + d * get_normal ((th/2) * pt.direction ());
pango_matrix_transform_point (&trans, &inter[X_AXIS], &inter[Y_AXIS]);
points[d].push_back (inter);