Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!samsung!uakari.primate.wisc.edu!dali.cs.montana.edu!milton!brucec%phoebus.phoebus.labs.tek.com@RELAY.CS.NET From: brucec%phoebus.phoebus.labs.tek.com@RELAY.CS.NET (Bruce Cohen) Newsgroups: sci.virtual-worlds Subject: Re: "Space" -- electron energies Message-ID: Date: 18 Aug 90 19:13:33 GMT References: <9007250107.AA01311@hitl.vrnet.washington.edu> Sender: hlab@milton.u.washington.edu Organization: Tektronix Inc. Lines: 32 Approved: hitl@hardy.u.washington.edu In-Reply-To: wex@dali.pws.bull.com's message of 17 Aug 90 22:58:42 GMT Fcc: VirtualWorlds In article wex@dali.pws.bull.com (Buckaroo Banzai) writes: [I wrote:] > There are two choices: the kludgier one is to pick a > plane transverse to the third axis to put the 2D object in, that is, > identify ill-defined positions with a unique position. The cleaner way is > simply to place all the 2D objects in a plane transverse to the 3D axis, > and then extrude them parallel to it. Having done that, it's easy to see > where the true 3D objects intersect with the extrusions. [and Alan Wexelblat replied:] > What about a 1D object? (I also don't see why one method is "kludgier" than > another. Yours, it would seem, would obscure a lot more of the display. > Also, if you're trying to convey additional information with the objects > (auto-icons again), extrusion may cause things to mean more than they ought. > Shapes are important, too :-) > Yes, extrusion has its problems too, though they can be ameliorated with clever graphic solutions like translucent volumes, etc. (I'll try to say more about this in a later posting when I have more time). I guess I feel that selecting an arbitrary position for something which ereally has no position does damage to the underlying data you are trying to show, probably a remnant of my time in "scientific visualization". Both solutions will have their uses. -- --------------------------------------------------------------------------- NOTE: USE THIS ADDRESS TO REPLY, REPLY-TO IN HEADER MAY BE BROKEN! Bruce Cohen, Computer Research Lab email: brucec@tekcrl.labs.tek.com Tektronix Laboratories, Tektronix, Inc. phone: (503)627-5241 M/S 50-662, P.O. Box 500, Beaverton, OR 97077