Stars don't show after 10s of millions of light years

Description: Report bugs, bug fixes and workarounds here.

Dimethylmercury
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Dimethylmercury
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#1by Dimethylmercury » 05.09.2017, 17:28

PC Specs: Intel Pentium N3540 @2.16 GHz, 4 GB RAM, 64-bit system, Intel HD Graphics card.
Celestia 1.6.1

I am not sure if this was posted before, since I couldn't find anything related to it.

When I made a star in a galaxy Centaurus A, which is 11 million LY away, stars show perfectly fine.
But when I tried putting the stars into my favourite Whirlpool Galaxy, which is 23 million LY away, it only was invisible.

Is this an overall program restriction, and is there any way out of this?

selden
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selden
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#2by selden » 06.09.2017, 00:24

Yup. That appears to be beyond the max drawing distance for STC objects.

You seem to be doing better than I am. The maximum distance that I can persuade the Windows version of Celestia v1.6.1 (downloaded from SourceForge) to draw stars is between 10.22 and 10.23 M LY, maybe within about 100 LY of the latter..

A workaround might be to use DSC objects instead: a Nebula with a Mesh that looks like a star, for example. Unfortunately, orbits, planets, and similar objects won't work with them.

DSC GlobularClusters aren't drawn correctly that far away, either. :(
Selden

John Van Vliet
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John Van Vliet
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#3by John Van Vliet » 06.09.2017, 05:03

there is a easy hack for that
BUT
if you have many stars and planets at a large distance there is a performance hit on the starDB

edit
src/celengine/stardb.cpp

line 48
then rebuild celestia

a star and planet at 320 million LY
Screenshot_20170906_005445.png

Dimethylmercury
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Dimethylmercury
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#4by Dimethylmercury » 09.09.2017, 11:16

I can't seem to find that stardb.cpp in celestia, neither /src folder...

selden
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selden
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#5by selden » 09.09.2017, 12:22

the file stardb.cpp should be in the directory celestia/src/celengine
If it isn't, you don't have all of the source code.

FWIW, under Windows I like to use the program "Everything" by David Carpenter. It locates NTFS files instantly (after having indexed everything, of course).
https://en.wikipedia.org/wiki/Everything_(software)

find is a Linux command which can be used to locate files.

p.s. If you don't have the source code, you can download the version of Celestia's source code that Alex is working on from https://github.com/CelestiaProject/Celestia
Selden


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