Xref: utzoo comp.sys.sgi:4244 comp.graphics:11770 Newsgroups: comp.sys.sgi,comp.graphics Path: utzoo!utgpu!watserv1!watcgl!jdchrist From: jdchrist@watcgl.waterloo.edu (Dan Christensen) Subject: Re: Rotations about an arbitrary axis Message-ID: <1990Jun1.194841.11194@watcgl.waterloo.edu> Organization: Computer Graphics Lab, University of Waterloo References: <9005171647.AA14106@baby.swmed.utexas.edu> <1990May31.171937.14296@watcgl.waterloo.edu> Date: Fri, 1 Jun 90 19:48:41 GMT Lines: 17 In article spencer@eecs.umich.edu (Spencer W. Thomas) writes: >In article <1990May31.171937.14296@watcgl.waterloo.edu> jdchrist@watcgl.waterloo.edu (Dan Christensen) writes: > >> But there is more than one rotation mapping a vector V1 to a vector V2. >> The final result can be oriented in any way about V2. The original >> poster indicated that he wanted the one that rotates about V1xV2, >> ie. the most "direct" rotation. I don't think that your solution >> does this. > >I agree that the problem, as I stated it, is ill-defined. However, my >solution definitely maps the normal vector onto itself, by >construction. Sorry, your solution does work. My point was that the problem was ill-defined. Thanks for working out the details. Dan Christensen