Bug in plotting 3d polyhedron with rays, add option polygon='rainbow'

[yuan-zhou]

Visually, there is no different between the two plots:

p = Polyhedron(rays=[(0, 0, 1)],lines=[(1, 0, 0), (0, 1, 0)])
p.plot()
q = Polyhedron(lines=[(1, 0, 0), (0, 1, 0)])
q.plot()

The bug seems to be caused by sage.geometry.polyhedron.Projection._init_solid_3d, which discards the rays. There might also be a bug in sage.geometry.polyhedron.Projection._init_lines_arrows, but I'm not sure how to plot the arrows in this example.

CC: @mkoeppe @fchapoton @dcoudert @slel @jplab

Component: geometry

Author: Yuan Zhou

Branch/Commit: fbd18ca

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/31802

[yuan-zhou]

Branch: u/yzh/bug_in_plotting_3d_polyhedron_with_rays

[sagetrac-git]

Commit: 331c351

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

331c351

Plot 3d polytope with rainbow colors

[sagetrac-git]

Changed commit from 331c351 to 1909108

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

1909108

revise Projection._init_lines_arrows, take care of rays/lines that are not on a facet, small edits to plotting arguments and docstrings

[yuan-zhou]

Author: Yuan Zhou

[sagetrac-git]

Changed commit from 1909108 to bf0b645

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

bf0b645

fix bug on the number of polygons

[sagetrac-git]

Changed commit from bf0b645 to d27c745

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

d27c745

improve implementation for Polyhedron 3d plot argument polygon=rainbow