 
 
 
 
 
 
movie distortortion
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg308] movie distortortion
- From: mwl at trantor.Jpl.Nasa.Gov (Martin W. Lo)
- Date: Fri, 9 Dec 1994 10:49:13 -0800
Dear mathgroup,
I'm having problem with ShowAnimation[].  I'm trying to animate an orbit
about earth.  When I animate the orbit by itself, it works just fine.  But
when I include the earth, the scale keeps changing on me.  I thought by
providing PlotRange, the scale is supposed to be fixed.
Setting BoxRatios -> {1,1,1} makes doesn't solve the problem;
it also causes the sphere to go through a squashing deformation.
What should I do to fix this?
Thanks for your help.
Martin Lo
Here is my code fragment:
data = an orbit about earth
ShowAnimation[Table[{Graphics3D[{AbsoluteThickness[1], 
      Line[Take[data, n]]}],earth3D}, nnn],
      PlotRange -> ppp]
nnn = {n,1,300,30}
ppp = {{-7000, 7000}, {-7000, 7000}, {-7000, 7000}}
CENTER  = {0.,0.,0.};
earth3D = ParametricPlot3D[{r Sin[u]*Cos[v]+CENTER[[1]],
                     r Sin[u]*Sin[v]+CENTER[[2]],
                     r Cos[u]       +CENTER[[3]]}, 
                     {u, 0, Pi}, {v, 0, 2*Pi},
                     Boxed -> False,Axes->False]

