Do away with strokeIndices and construct Geometry directly with edges

[inaridarkfox4231]

Currently, strokeIndices is used to define edges regardless of faces when composing geometry.

However, the way to configure edges using it is to copy the contents of strokeIndices to edges as they are in _makeTriangleEdges(), which is a wasteful process.

So, I wanted to rewrite the processing method so that edge information is stored in edges from the beginning.
StrokeIndices is not prepared even at initialization, and in that sense it is not a very natural process.

Also, when creating APIs in the future, I thought it would cause confusion if there was a way of processing that didn't matter which way, so I wanted to unify it.

In addition to that, the specification of model() was changed so that edges are constructed from faces only when edges are not provided in the model function. This allows p5.Geometry to construct a geometry without losing its contents for edges, even if it has no faces and only edges, or constructs its own edges.

Resolves #6120

Changes:

• replace "strokeIndices" with "edges" in arc, box, triangle, rect and avoid calling _makeTriangleEdges()
• In _makeTriangleEdges(), omit the processing performed for strokeIndices
• In model(), construct edges from faces only when edges.length is 0.

Screenshots of the change:

Demo: patch_model_2

I tried it, but the box, triangle, arc, and rect whose specifications were changed here were all drawn as usual.

PR Checklist

• npm run lint passes
• Inline documentation is included / updated
• Unit tests are included / updated

[davepagurek]

Thanks for implementing this, it makes geometry code an extra bit cleaner!

[inaridarkfox4231]

thanks for merge! ('ω')