GRL not working for points defined as [ ] [ ] after optimizing performance

[roland]

Optimizing performance of GreasedLineMesh._setPoints

This PR unfortunatelly introduced a bug: points: [ [ -1,1,0, 1,1,0 ], [ -1,-1,0, 1,-1,0 ] ] Produces: [image] Expected: [image] Cna you check it please?

[kzhsw]

Optimizing performance of GreasedLineMesh._setPoints

This could be the same index thing reported here, seems this pr fixes it.

[roland]

Tested in the snapshot environment and it works. Thx!