CylinderSector doesn't properly generate planes for off origin centers

[MicahGale]

Bug Description

If you create an openmc.model.CylinderSector that is not located at the origin, the planes that define the sector do not appear to intersect the center.

Reading the code it seems like this issue is this line and the next few. It seems to me that the assumption with these planes is that they are going through the origin and they are parallel to the Z-axis. I tried to read through #2027 to better understand the logic, and there doesn't seem to be any discussion of this. @yardasol, am I missing something?

Steps to Reproduce

1. Create an off-origin cylinder sector

import openmc
center = (10, 0, 0)
sector = openmc.model.CylinderSector(1.0, 1.1, 90, 95, center[0:2])

2. If we try to plot this we get errors, likely due to the null set region (related to Cell.plot does not have any math sanity checks #3015):

cell = openmc.Cell(region=-sector)
cell.plot()

This leads to errors shown in #3015.

3. What is going on with these surfaces?

>  print(sector.inner_cyl, sector.outer_cyl, sector.plane1, sector.plane2)
Surface
        ID                 =    16
        Name               =
        Type               =    z-cylinder
        Boundary           =    transmission
        Coefficients
x0                  =   10
y0                  =   0
r                   =   1.0
 Surface
        ID                 =    17
        Name               =
        Type               =    z-cylinder
        Boundary           =    transmission
        Coefficients
x0                  =   10
y0                  =   0
r                   =   1.1
 Surface
        ID                 =    18
        Name               =
        Type               =    plane
        Boundary           =    transmission
        Coefficients
a                   =   0.10000000000000009
b                   =   -6.123233995736777e-18
c                   =   0.0
d                   =   0.0
 Surface
        ID                 =    19
        Name               =
        Type               =    plane
        Boundary           =    transmission
        Coefficients
a                   =   0.09961946980917458
b                   =   0.008715574274765825
c                   =   0.0
d                   =   0.0

The cylinders are properly located. However it looks like the planes go through the origin. This can be easily confirmed:

In [22]: half = -sector.plane1

In [23]: epsilon = 1e-6

In [24]: (epsilon, 0, 0) in half
Out[24]: False

In [25]: (-epsilon, 0, 0) in half
Out[25]: True

Therefore, the plane does go through the origin.

Environment

• openmc: 0.14.0

[yardasol]

Good catch @MicahGale! I just opened PR #3018 to fix this!