[geom] Add per_vertex_thickness to to_spline()

phi/geom/_spline_solid.py

@@ -306,26 +306,34 @@ def __add__(self, other):
         return NotImplemented
 
 
-def to_spline(geo: Geometry, /, variable_attrs=('points', 'thickness', 'fillet'), value_attrs=(), rel_separation=1e-5) -> SplineSolid:
+def to_spline(geo: Geometry, /, per_vertex_thickness=True, variable_attrs=('points', 'thickness', 'fillet'), value_attrs=(), rel_separation=1e-5) -> SplineSolid:
     assert geo.spatial_rank == 3, f"SplineSolid must be fit to 3D geometry but got {geo}"
     if isinstance(geo, Cylinder):
         tips = dpack(geo.face_centers['bottom,top'], 'u:s')
         right = orthogonal_vector(geo.up)
         side_eps = geo.depth * rel_separation * right * wrap([-1, 1], 'v:s')
         points = tips + side_eps
-        return SplineSolid(points, geo.radius * 2, {'u-': wrap(0.), 'u+': wrap(0.), 'v-': wrap(1.), 'v+': wrap(1.)}, {'u': 1, 'v': 1}, variable_attrs, value_attrs)
+        thickness = geo.radius * 2
+        if per_vertex_thickness:
+            thickness = expand(thickness, spatial(points))
+        return SplineSolid(points, thickness, {'u-': wrap(0.), 'u+': wrap(0.), 'v-': wrap(1.), 'v+': wrap(1.)}, {'u': 1, 'v': 1}, variable_attrs, value_attrs)
     elif isinstance(geo, BaseBox):
         thickness, th_idx = math.min((geo.size, range), 'vector', key=geo.size)
         u_idx, v_idx = (th_idx + 1) % 3, (th_idx + 2) % 3
         vu, vv = geo.rotation_matrix[{'~vector': u_idx}], geo.rotation_matrix[{'~vector': v_idx}]
         su, sv = geo.size.vector[u_idx], geo.size.vector[v_idx]
         u = vu * su * wrap([-.5, .5], 'u:s')
         v = vv * sv * wrap([-.5, .5], 'v:s')
-        return SplineSolid(geo.center + u + v, thickness, {'u-': wrap(0.), 'u+': wrap(0.), 'v-': wrap(0.), 'v+': wrap(0.)}, {'u': 1, 'v': 1}, variable_attrs, value_attrs)
+        points = geo.center + u + v
+        if per_vertex_thickness:
+            thickness = expand(thickness, spatial(points))
+        return SplineSolid(points, thickness, {'u-': wrap(0.), 'u+': wrap(0.), 'v-': wrap(0.), 'v+': wrap(0.)}, {'u': 1, 'v': 1}, variable_attrs, value_attrs)
     elif isinstance(geo, Sphere):
         thickness = geo.radius * 2
         u, v = (rel_separation * thickness * math.meshgrid(u=2, v=2)).vector
         points = geo.center + wrap([u, v, 0], geo.shape['vector'])
+        if per_vertex_thickness:
+            thickness = expand(thickness, spatial(points))
         return SplineSolid(points, thickness, {'u-': wrap(1.), 'u+': wrap(1.), 'v-': wrap(1.), 'v+': wrap(1.)}, {'u': 1, 'v': 1}, variable_attrs, value_attrs)
     else:
         raise NotImplementedError(type(geo))