Fix polyhedron vertices - points

[ericgozzi]

Fixes the vertices setter to convert list[Point] into a list of coordinates list[list[int]]. The Polyhedron.vertices attribute now always returns a list of vertices (list[list[int]]).

The behavior now matches the docstring.

• Added a new test test_polyhedron_vertices in test_polyhedron.py to verify that the Polyhedron class correctly handles both lists of coordinates and lists of Point objects as vertices.
• Imported Point in the test file to support the new test case.

What type of change is this?

• Bug fix in a backwards-compatible manner.
• New feature in a backwards-compatible manner.
• Breaking change: bug fix or new feature that involve incompatible API changes.
• Other (e.g. doc update, configuration, etc)

Checklist

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• I added a line to the CHANGELOG.md file in the Unreleased section under the most fitting heading (e.g. Added, Changed, Removed).
• I ran all tests on my computer and it's all green (i.e. invoke test).
• I ran lint on my computer and there are no errors (i.e. invoke lint).
• I added new functions/classes and made them available on a second-level import, e.g. compas.datastructures.Mesh.
• I have added tests that prove my fix is effective or that my feature works.
• I have added necessary documentation (if appropriate)

[gonzalocasas]

mmm... this has two problems:

1. performance is not the best, because it iterates twice over all vertices (first to check all() and then to convert to lists), and
2. [this is a bit more problematic] vertices are not always going to be instances of Point, compas accepts lists/tuples/etc that can be iterated as valid points, so, this code would break that assumption

may I ask what's the trigger for changing this? Have you observed a bug in other code?

[tomvanmele]

the behaviour of Polyhedron indeed could/should be improved. however, i would actually rather remove the setters instead (also the one for faces). the proposed change imposes a conversion that is unnecessary imo, and doesn't improve the fragile relationship between vertices and faces...

[chenkasirer]

I believe the issue here is that Polyhedron can be created with either a list of Point or a list[list[float]] (which I find OK) but that gets directly stored in _vertices and directly fetched using the public property.

therefore you'd get a different type from polyhedron.vertices depending on how it was created. this both violates the docstring which states the return value is always list[list[float]] and - god help us - it violates the sacred covenant of encapsulation :0

>>> pl = Polyhedron(vertices=[[1.0, 2.0, 3.0], [4.0, 5.0, 6.0], [1, 2, 3], [4, 5, 6]], faces=[1, 2, 3])
>>> pl.vertices
[[1.0, 2.0, 3.0], [4.0, 5.0, 6.0], [1, 2, 3], [4, 5, 6]]
>>> 
>>> pp = Polyhedron(vertices=[Point(1.0, 2.0, 3.0), Point(4.0, 5.0, 6.0), Point(1, 2, 3), Point(4, 5, 6)], faces=[1, 2, 3])
>>> pp.vertices
[Point(x=1.0, y=2.0, z=3.0), Point(x=4.0, y=5.0, z=6.0), Point(x=1.0, y=2.0, z=3.0), Point(x=4.0, y=5.0, z=6.0)]

[yck011522]

I knew one day someone would dig up this polyhedron can of worm. I'm now excited to watch how it unfolds.

[chenkasirer]

perhaps something more like this?

Suggested change

	if all(isinstance(vertex, Point) for vertex in vertices):
	vertices = [[vertex.x, vertex.y, vertex.z] for vertex in vertices]
	self._vertices = vertices
	self._vertices = []
	for vertex in vertices:
	self._vertices.append([*vertex])