Polyhedron is very fast with my version 2014.10.02 I had originally made solids with multiple polyhedron statements and successfully printed off the result with mattercontrol but then was investigating an issue after some time and discovered my models had multiple intersecting vertices. After converting my code to make a single polyhedron with a superset of all data, I found my renders were changed from hour long to a few seconds. Now I routinely run renders with 100,000 + facets and get times of around a minute or less. -- View this message in context: http://forum.openscad.org/Terrain-modeling-tp6985p12733.html Sent from the OpenSCAD mailing list archive at Nabble.com.