Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!usenet.blueworldhosting.com!feeder01.blueworldhosting.com!border4.nntp.dca.giganews.com!backlog4.nntp.dca3.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!newspeer1.nac.net!newspump.sol.net!post2.nntp.sol.net!posts.news.twtelecom.net!nnrp3.twtelecom.net!not-for-mail From: christopher arthur Newsgroups: comp.soft-sys.math.mathematica Subject: access to perspective routines Date: Mon, 5 May 2014 07:03:05 +0000 (UTC) Sender: steve@smc.vnet.net Approved: Steven M. Christensen , Moderator Message-ID: Reply-To: chris.arthur1@gmail.com Lines: 10 Organization: Time-Warner Telecom NNTP-Posting-Date: 05 May 2014 07:09:21 GMT NNTP-Posting-Host: ae97af6b.news.twtelecom.net X-Trace: DXC=o>DNRghg^;@\o7M8kQj6M;[h;PUXBgbD\BjXfi;a<@IEFiONJ7[GoFa9SJE2MJ`MM X-Complaints-To: abuse@twtelecom.net X-Original-Bytes: 1152 Xref: csiph.com comp.soft-sys.math.mathematica:16907 Hello, I'm thinking about changing an aspect of the way mathematica computes perspective 3D-graphics. What I would like to do is define a function that operates on my polygons differently depending on whether they are visible or not from the current viewpoint. It might be as simple as just being able to Sow[] the polygons into two groups. Chris