Lbutt extend cross

[chenkasirer]

• Merged the functionality of DecomposeBeam and ShowBeamFrame and removed the latter.
• Added visualization for beams faces and their normals to DecomposeBeam.
• Added two flags that can be used when assigning L-butt joints in a multi-beam joint situation:
  • modify_cross when set to False (default True) tells CT no to modify the cross beam (which might already be joined)
  • reject_i when set to True (default False) BeamJoiningError is raised when the main and cross meet in an I topology. I is generally allowed with L-butt but might not be desired when the cross is already joined at the same end.

When both are left as default, the L-butt behavior is as before.

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_timber.datastructures.Beam.
• I have added tests that prove my fix is effective or that my feature works.
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[obucklin]

my concern is, what happens if someone wants to make a butt joint with beam incidence angle of < 45deg? In this case, the joint will have one of the ends as cfr or index will be 5 or 6, even though the user wants to join in the old way with just the 4 main faces.

Should we add this as a kwarg in the GH component? it could be a cutoff angle with default of 45.

[chenkasirer]

a sketch here would help.

but if I get it right though, what you're suggesting sounds like an l-miter, no?
otherwise, when considering only the 4 main faces like before this rework you would get something like this:

Basically L-Miter is the only joint we currently have that supports an I topology (knows how to handle end to end joining)