POV-Ray : Newsgroups : povray.general : vrotate question : vrotate question Server Time
27 Sep 2024 01:14:54 EDT (-0400)
  vrotate question  
From: jr
Date: 23 Aug 2024 07:25:00
Message: <web.66c8710ff5740dfef5bfc9b06cde94f1@news.povray.org>
hi,

the manual defines: "vrotate(A,B) Rotate A about origin by B."  yet when I
rotate a simple point, at 180 degrees the output is .. unexpected, not <-1,0,0>.
 can someone please explain ?


#version 3.8;

global_settings {assumed_gamma 1}
box {0,1}

#declare P = <1,0,0>;

#debug concat("rot 000 : ",vstr(3,vrotate(P,0),",",0,2),"\n")

#debug concat("rot 090 : ",vstr(3,vrotate(P,90),",",0,2),"\n")

#debug concat("rot 180 : ",vstr(3,vrotate(P,180),",",0,2),"\n")

#debug concat("rot 270 : ",vstr(3,vrotate(P,270),",",0,2),"\n")



Persistence of Vision(tm) Ray Tracer Version 3.8.0-alpha.9945627.unofficial
....
==== [Parsing...] ==========================================================
rot 000 : 1.00,0.00,0.00
rot 090 : 0.00,0.00,-1.00
rot 180 : 1.00,-0.00,-0.00
rot 270 : 0.00,0.00,1.00


regards, jr.


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.