> High!
> 
> I implemented Thomas de Groot's suggestion for my Saturnian system model 
> (and will do this in the future also for the other planets, which also 
> all have some axial tilt) and started with rendering two views of Pan, 
> the innermost regular moon of Saturn (except for some 150 tiny 
> "moonlets" orbiting still more inward), from 5,000 and from 100 kms.
> 
> To get the camera centered on Pan, I had to rotate its location and 
> look_at vectors according to Saturn's axial orientation using vrotate():
> 
>     #declare Final_Pos_Pan = Pos_Saturn + vrotate(Pos_Pan, 
> <bodies[3][4]-(90-bodies[72][10]), 90-bodies[72][11], 0>);
>     #declare camPos = Final_Pos_Pan + 100 * <sin(radians(39)), 0, 
> cos(radians(39))>;
>     #declare camLook = Final_Pos_Pan;
> 
> Note that the camera still looks towards Pan from the ecliptic plane, 
> which is identical with the x-z plane; later on, I will use the 
> respective planet's (or moon's, in case of axially tilted moons like our 
> own Moon) equatorial plane as reference for camera positioning.
> 
> When zooming close to Pan, I had to divide the global scaling factor 
> (normally 13347) by 100, otherwise it would have been rendered 
> incompletely.
> 
> A real flaw is that Pan doesn't orbit within the Encke gap (see 
> http://en.wikipedia.org/wiki/Pan_(moon) ); I assume that this is caused 

> (or, as well, inaccuracies in building multipartite texture_maps from 
> them). Perhaps, in the more distant future, I'll replace this simple 
> "monolithic" ring by thousands of individual ring objects, thus allowing 
> individual thicknesses, corrugations and dynamic clump and tidal wave 
> structures.
> 
> Also for now, the moons are simple spheroids rather than realistic 
> asteroidal/small planet bodies with a real surface relief; for most of 
> Saturn's (and the other planets') small moons, the surface structures 
> would be entirely or mostly fictitious, with only vague hints at shapes 
> gleaned from Voyager, Galileo and Cassini probe photos.
> 
> See you in Khyberspace!
> 
> Yadgar
> 
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> 
> 
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> 
You have acuracy problems. That's why it got chopped like that.
You need more bits of precision than the 64 (80 internal) offered by the 
FPU.


Alain

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