#96 Large DSC models not drawn from distance

[Selden Ball]

Large DSC Nebula objects are not drawn if the viewpoint
is more than about 4MPc from their center. They need to be drawn when observed from an arbitrary distance,
at least to a distance of 1000 MPc.

In other words, one can no longer view the overall structure of the universe as shown by models generated from the various red-shift surveys.

This can be demonstrated with
http://www.lepp.cornell.edu/~seb/celestia/qagn.zip
(1.3MB)

You'll have to manually enable Nebula rendering, since this Addon's HTML page was created before separate Nebula rendering was available.

[Chris Laurel]

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I am able to view the objects in your example from up to about 4000 MPc. Is this what you meant? However, this limit is still not enough. I think that another factor of 10 would be adequate.

[Selden Ball]

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It's almost as if different models have different observation limits.

I think the viewpoint distance limit needs to be lot larger
than the 13.7GLY look-back distance so one can rotate models and get
a feel for their shapes from distances and with magnifications which
minimize perspective distortions.

It'd also be nice to be able to view models that use co-moving dimensions
instead of the distances we currently see. Their dimensions would be a *lot* larger, since
the distances between the most distant objects would have expanded dramatically by now.

[Chris Laurel]

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I am able to view the objects in your example from up to about 4000 MPc. Is this what you meant? However, this limit is still not enough. I think that another factor of 10 would be adequate.

[Selden Ball]

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As you point out, 4,000 MPc really is too close.
The viewpoints in the HTML file of the Addon are at about 8,500 and 10,000 MPc.
Viewpoint distances greater than those are desirable, too, I think.

I'm not sure what I was doing wrong when I was having problems at smaller distances on my home system. I need to regenerate the Addons with HTML files that enable Nebula rendering: maybe that was part of the problem.

[Chris Laurel]

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This appears to have been fixed by setting the size of the deep sky object octree to 1.0e11 light years.

[Selden Ball]

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problem fixed as of 17-nov-2007