Aperture stop has no aperture in Plot3D

[ederag]

From the Tutorial,

# Example 4.8: Chief ray for the system from the example 4.3 with an aperture stop between the two lenses

L1=SphericalLens(radius=25,curvature_s1=1./100.,curvature_s2=-1./100,thickness=10,material=material.schott["BK7"])
L2=SphericalLens(radius=25,curvature_s1=1./100.,curvature_s2=-1./100,thickness=10,material=material.schott["BK7"])

C=CCD()

AP=Stop(shape=Circular(radius=(30)), ap_shape=Circular(radius=(25)))

S=System(complist=[(L1,(0,0,100),(0,0,0)),(L2,(0,0,120),(0,0,0)),(AP,(0,0,110),(0,0,0)), (C,(0,0,150),(0,0,0))  ],n=1)

CHR=chief_ray_search(S,AP,(0,10,0),(0,-1,1))

S.ray_add(CHR)
S.propagate()
Plot3D(S,center=(0,0,100),size=(150,100),scale=4,rot=[(0,pi/2.1,0)])

The aperture stop should be open in the center.
The ray passes through, so it looks like a plot issue only.
Yet this makes it difficult to check the aperture diameter.

Tested in current development version (d3a8674) and

jupyter (1.0.0)
jupyter-client (5.3.1)
jupyter-console (6.0.0)
jupyter-core (4.5.0)
pythreejs (2.1.1)