[OpenSCAD] STL without render?

Marius Kintel marius at kintel.net
Fri Jun 3 11:13:30 EDT 2016


> On Jun 3, 2016, at 04:23 AM, nop head <nop.head at gmail.com> wrote:
> 
> I don't think B-rep is the problem. It is the fact that CGAL appears to do nothing to short cut unions. I.e. it doesn't check for completely disjoint objects and it doesn't seem to look for facets with no intersections and pass those straight through.

..which I believe is an effect of CGAL defining its B-Rep as Nef polyhedrons, which is an intersection of infinite planes, which makes it expensive to calculate the bounding box. I’m not 100% certain of the internals, but it’s pretty clear that they haven’t spend much (or any) time on performance optimization.

 -Marius





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