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Viewpoint Scaling

  • To: mathgroup at smc.vnet.net
  • Subject: [mg16671] Viewpoint Scaling
  • From: "Naum Phleger" <naum at condor.physics.ucsb.edu>
  • Date: Fri, 19 Mar 1999 12:54:17 -0500
  • Organization: UCSB
  • Sender: owner-wri-mathgroup at wolfram.com

    I have received lots of help, but what I really want to know is the 
algorithm that is used to scale the points in the ViewPoint option for 3D
graphics. Here is a simple example that illustrates the problem.  Here are
the points that I want to view my globe from (in {x,y,z} form).

{1,0,0} {sqrt 2, sqrt 2,0} {1,0,0} {-sqrt 2,sqrt 2, 0} {-1,0,0}, ...

or in {r,theta,fi} form

{1,0,0} {1,0,pi/4} {1,0,pi/2} {1,0,3pi/4} {1,0,pi} ...

The problem I have is that with this list, the odd points give a smaller
image back, and it is of set because the box is oriented differently.

    What I want to do is enter my view points in such a way that the only
difference between successive images is a rotation, no translation or
scaling.  Where can I find the algorithm that Viewpoints uses?  Thank you
for any help.
--

Naum Phleger

Gwinn Group:                    Naum's House:
University of California        6735 Trigo Rd. Apt. A
Santa Barbara, CA 93106         Isla Vista, CA 93117
Phone: (805) 893-8656           Phone: (805) 961-8282

naum at condor.physics.ucsb.edu



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