NGC 6720, the ring nebula

[AstroBoy]

New nebula add-on for Celestia : NGC6720 the ring nebula



You can download it on my website

http://membres.lycos.fr/tompouce00/

by AstroBoy

[bh]

Looks great...can you add a star cluster to go with it. I find if you add a 'sub system' with some moons and stuff you really get a great animation.

Keep it up...bh.

[Vicware]

As always, you click on download on your page and the following
page comes up:

http://www.multimania.lycos.fr/error/re ... GC7293.zip

A page in French, as you see, and then after a few seconds it loops
back to your download page... and so it goes.

Hope some day you straighten this out - I would love to see your Nebula
in Celestia.

Vic

[Guest]

I made some modifications.
So retry it and tell me what...

[AstroBoy]

Reply above is from me, sorry, orgot to log in !!!

[Wiz Eutropio]

Sorry, but link DOESN'T work again, or if I can download the file with some programs (as DAP) explorer tell me it is a not valid file or that the ZIP is corrupted.

[billybob884]

i downloaded it and it worked fine, but when i installed it i noticed one, the mesh is just a see-through grey ball, and two, the dsc names the object with a 1 instead of a 7

[praesepe]

I've also noticed a strange effect on the nebula (great work by the way, your texture is really cool).When viewing it from the sides some areas seem to desapear. I was wondering why was this happening (and its not caused by a transparency level on the mesh itself, the transparency is defined on the alpha channel of the texture) so I opened on 3Dmax and found what was happening. The mesh is a box with a really tiny side wich is not mapped, as also the edges. Take a look:





Sorry to be so picky

[MrBatman]

i downloaded it and it worked fine, but when i installed it i noticed one, the mesh is just a see-through grey ball, and two, the dsc names the object with a 1 instead of a 7

I had this problem myself, and I think I know the answer.

You probably downloaded the planetary nebulae add-on. You need to go to the planetary_nebulae.dsc file, open it, find the entry for ngc6720, and delete that entry in the file.

You can then edit your ngc6720 - Ring Nebula.dsc file to look like this:

Code: Select all

Nebula "Ring Nebula"
{
   Mesh "ngc6720.3ds"
   Radius    0.93
   RA    18.8933333
   Dec    33.0333333
   Distance 2300
}

Nebula "NGC 6720"
{
   # Mesh "ngc6720.3ds"
   Radius    0.93
   RA    18.8933333
   Dec    33.0333333
   Distance 2300
}

Now it will go to either "Ring Nebula" or "NGC 6720".

[AstroBoy]

I've also noticed a strange effect on the nebula (great work by the way, your texture is really cool).When viewing it from the sides some areas seem to desapear. I was wondering why was this happening (and its not caused by a transparency level on the mesh itself, the transparency is defined on the alpha channel of the texture) so I opened on 3Dmax and found what was happening. The mesh is a box with a really tiny side wich is not mapped, as also the edges.

One way to correct this, I think, would be to deled unused polygons.

Gonna try it...

[selden]

AstroBoy,

I've been wondering... Why a flat model with a random rippley surface instead of one that's close to being a sphere? After all, most Planetary Nebulae are spherical or cylindrical or some other strange 3D shapes.

[AstroBoy]

I've been wondering... Why a flat model with a random rippley surface instead of one that's close to being a sphere? After all, most Planetary Nebulae are spherical or cylindrical or some other strange 3D shapes.

It's not spherical because those structure are to complex to be render as well as I would expect, So I use a flat model. But I don't like the billboard model, so I added some random fluctuation (that I prefer).

A second remarq : a billboard nebula can't be seen from the side, my does (even if it isn't very beautiful). It's only a question of estetical choice.