       Re: Mathematica Animation Problem

• To: mathgroup at smc.vnet.net
• Subject: [mg35447] Re: Mathematica Animation Problem
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Sat, 13 Jul 2002 03:48:16 -0400 (EDT)
• Organization: Universitaet Leipzig
• References: <agm551\$5at\$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Hi,

For[alpha = 0.0, alpha < 2 Pi, alpha = alpha + 0.1,
Plot3D[Exp[-(x^2 + y^2)], {x, -2, 2}, {y, -2, 2},
{ViewCenter -> {0.5, 0.5, 0.5},
ViewPoint -> {5 Cos[alpha], 5 Sin[alpha], 0.5}},
PlotRange -> {{-2, 2}, {-2, 2}, {-0.5, 1}}, SphericalRegion -> True,
Axes -> False
]
]

looks fine. You must switch off the axes labels, other wise the jumping
text labels will modify the center of the image.

Regards
Jens

Tobi wrote:
>
> Dear all,
>
> I hope someone can give me advice concerning the following Mathematica
> (Version 4.1) problem:
>
> I am trying to produce an animation of a circular "walk" around a 3D
> plot. I get the animation, but it looks like sometimes I get nearer to
> the plot and sometimes the plot looks more distant, so that I don't
> get the impression of walking on a circle.
>
> My guess is that I have not yet understood how the options
> "ViewCenter" and "ViewPoint" work.
>
> So here is what I wrote to produce the image sequence:
>
> For [alpha = 0.0, alpha < 2 Pi, alpha = alpha + 0.1,
>   Plot3D[ Exp[-(x^2 + y^2)], {x, -2, 2}, {y, -2, 2},
>           {ViewCenter -> {0, 0, 0},
>            ViewPoint -> {5 Cos[alpha], 5 Sin[alpha], 0.5}}]]
>
> So all viewpoints should lie on a circle of radius 5 around the origin
> and with a constant height of 0.5. But the visual impression is
> different, as decribed above. Anyone knows what's wrong?
>