CenterOf.GEOMETRY seems to return non correct center values

[bernhard-42]

I have a simple chamfered box:

with BuildPart() as b:
    Box(1, 2, 3)
    Chamfer(*b.edges(), length=0.2)

To my surprise, group_by delivers only 6 of 8 faces. Reasons seems to be CenterOf.GEOMETRY:

[o.center(CenterOf.BOUNDING_BOX).Z for o in b.faces().sort_by(Axis.Z)[-9:]] returns [1.4, 1.4, 1.4, 1.4, 1.4, 1.4, 1.4, 1.4, 1.5], i.e. all except the top face have z-value 1.4

[o.center(CenterOf.GEOMETRY).Z for o in b.faces().sort_by(Axis.Z)[-9:]] returns [1.35, 1.35, 1.4, 1.4, 1.4, 1.4, 1.4, 1.4, 1.5], i.e. with the default geometry center, two of the triangles have a smaller z-value than the other two.

[gumyr]

With your PR, can this issue be closed now?

[bernhard-42]

The situation is better, I now get 4 chamfered rectangles with [-2] and the 4 chamfered triangles with [-3] If I could provide the center param to group_by, I could use BB which would give me back all 8 rectangles and triangles.

Independent of this use case, given the sensibility of center, I would love to see sort_by and group_by getting an additional parameter center_of with GEOMETRY as default. What do you think?

[gumyr]

Adding the center_of seems like a good idea given the complex of the "simple" center calculation.

[gumyr]

center is documented here: https://build123d.readthedocs.io/en/latest/center.html