Black hole model does not display properly

[fsgregs]

I think I saw this mentioned somewhere else, but I can't find the reference. When I visit the Black Hole add-on using 1.3.2pre8, I discover that the center "hole" is no longer black. The sphere appears to be "reflecting" the surroundings and is now multicolored.

Here is a screenshot.




I don't believe Celestia did this in 1.3.2pre7, although I cannot be sure. It didn't do it in 1.3.1

Thanks

Frank

[High Dark Templar]

It seems that I must rebuild my black hole, I will try in the next weeks

[fsgregs]

Hi Dark Templar:

Something is happening in Celestia 1.3.2pre8 that is messing up model meshes and close-in views. It is not only your black hole model that is no longer displaying properly. Several posts recently have reported other model add-ons no longer displaying properly, particularly if they are big files. Also, recently, I went to the surface of Earth using the big VT texture and discovered that the edges of the frame broke up into big ugly black "V"s as I panned around. Even changing the elevation to 5 km did not help. This did not happen in Celestia 1.3.1.

Before you redo your add-on, perhaps Chris could figure out what may have changed in 1.3.2 to be doing this. Models are one of the best things about Celestia and it would be a big step backward if an upgrade to the program causes a problem in displaying model meshes. Maybe it has something to do with Chris's desire to utilize Nvidia FX cards. If that is the cause, I currently have a GeForce 4 TI 4200 which is only about 8 months old. I'd sure hate to have to buy an FX after I just bought the GeForce 4 less than a year ago.

Regards,

Frank

[Guest]

Thanks for the explication, today after my first post, I tested the black hole and it works fine in my PC, I was puzzled but your post answer my doubts... I have a Nvidia FX card.

I hope Chris will solve this trouble as soon as possible.

[Bob Hegwood]

Don't know if means anything or not, but the Black Hole display is
also screwed on my non-graphics enhanced machine now too.

Thanks, Bob

PS - System Info in Signature.

[chris]

It looks to me to be a bug. I should be able to get it fixed before 1.3.2 is done.

--Chris

[selden]

Guys,

There at least three different black hole models.
Which one do you mean?
Where can it be downloaded?

Asking the developers to search though all the Addons trying to find one that might not be working makes it unlikely that the problem will be fixed.

[Bob Hegwood]

Sorry Selden,

Didn't realize that there WAS more than one Black Hole add-on. The one I was
using is Jorge Omar Leyra Sobrino's package which can be downloaded from
either the Celestia MotherLode or Mike M's site.

This add-on worked perfectly prior to Celestia 1.3.2 Pre8, and it does still
work. The problem is that the center of the Black Hole now shows a non-black
texture which appears to be a reflection of the surrounding debris which is
falling into the "Black Hole."

Thanks, Bob

[Bob Hegwood]

Just so's you know about it, the Black Hole model is still
screwed under 1.3.2 Pre10.

Take care, Bob

[selden]

Unfortunately, it turns out that the model will have to be modified.

Celestia now applies a texture specified in an SSC model to the entire model. Previously, the texture was applied to a whatever set of submeshes appeared before the first material change. Chris has no plans to change this new behavior.

According to Chris, the right way to make the black hole is to assign separate materials to the disk and sphere inside the model. He's derived a new black hole add-on that does exactly this, and it can be downloaded from http://www.shatters.net/~claurel/celestia/files/blackhole-cmod.zip

[ANDREA]

He's derived a new black hole add-on that does exactly this, and it can be downloaded from http://www.shatters.net/~claurel/celestia/files/blackhole.zip

Hello Selden, this link doesn't work for me.
It gives Error 404
By

Andrea

[selden]

Andrea,

I got the name wrong. Sorry.

Please try
http://www.shatters.net/~claurel/celestia/files/blackhole-cmod.zip

(I corrected it above, too.)

[ANDREA]

Andrea, I got the name wrong. Sorry.
Please try http://www.shatters.net/~claurel/celestia/files/blackhole-cmod.zip (I corrected it above, too.)

Thanks a lot Selden, this is OK.
By

Andrea

[fsgregs]

Selden:

Thanks for the info, and Chris, thanks for the new model. However, that raises a big question. There are probably 30 or 40 3ds meshes in Celestia's add-ons that use a medres texture for only part of the model, similiar to the Black Hole model. Hasn't that been the "norm" for 3ds in the past? Does this mean that a lot of other models in the add-on repository will also have to be redone? I haven't visited many of them recently but I use over 50 spacecraft models (for example) in two of my Activities, so I wonder if I'm in for a bad surprise when I do visit them?

Frank

[Bob Hegwood]

Selden and Others...

I hate to be the bearer of bad news, but the new model is screwed too.

On my system, the black center of the new model keeps disappearing,
and/or shows itself with jagged facets where the center should be a smooth,
black ball. Just thought I'd let you know about it in case this is going to
affect *every* model we have currently. Haven't seen any other faceted
objects yet, but really haven't looked exhaustively either.

Take care, Bob

[chris]

Selden:

Thanks for the info, and Chris, thanks for the new model. However, that raises a big question. There are probably 30 or 40 3ds meshes in Celestia's add-ons that use a medres texture for only part of the model, similiar to the Black Hole model. Hasn't that been the "norm" for 3ds in the past? Does this mean that a lot of other models in the add-on repository will also have to be redone? I haven't visited many of them recently but I use over 50 spacecraft models (for example) in two of my Activities, so I wonder if I'm in for a bad surprise when I do visit them?

Sometimes it's best to sacrifice a bit of backward compatibility in order ease future development. That's the case with this change in the way textures are applied to 3DS meshes. I think that the black hole is an unusual case. Most of the 3DS meshes I've tried look the same in 1.3.2pre10 as in previous versions.

--Chris

[chris]

I hate to be the bearer of bad news, but the new model is screwed too.

On my system, the black center of the new model keeps disappearing,
and/or shows itself with jagged facets where the center should be a smooth,
black ball. Just thought I'd let you know about it in case this is going to
affect *every* model we have currently. Haven't seen any other faceted
objects yet, but really haven't looked exhaustively either.

I'm very surprised . . . are you sure you're viewing it with 1.3.2pre10? In pre10, I fixed a bug that caused severe corruption of the black hole (and, as it turned out, any ssc object with mass defined.) If in fact you are seing the problem on pre10, could you post a screenshot?

--Chris

[Bob Hegwood]

Chris,

I have but one version of Celestia on my PC, and it is now 1.3.2 Pre10.

Can I e-mail you a screenshot? My deal with Earthlink is about to close my
site until the end of the month because I'm now getting waaayy too much
traffic and usage for my "free" site. This is what I am being told now that
I'm getting over a 100 visitors each day, and even though I'm actually paying
for the site as part of my Earthlink account. Sheesh!

I'll send you an e-mail copy.

Thanks, Bob

[fsgregs]

Chris, I can confirm that the new black hole model is still messed up. It is now black, but when you approach it, the black sphere breaks up into a series of half-circles. First, it disappears, then reappears as a 1/4 circle hovering above the accretion disk in mid-air, then a new circle begins to grow under it and merges with it, then it too shrinks to a 1/4 circle and the cycle continues. Here are two screenshots:

Notice the black hole has become two images one above the other:



As you continue to move closer, the above image becomes this:




This is happening in one form or another to other models. Worse, many of the models we use are becoming partly transparent as you approach them. A good example is the big "2001 Space Station" from the movie. It is wonderfully rendered and looks great in 1.3.1. You can approach it and even fly through its spokes, or dock with it in its landing bay. In 1.3.2pre 8 and pre 10, however, the model breaks up as you approach it. Panels suddenly become transparent so you can see inside the model, then as you approach closer, they become opaque but other panels become transparent. Here are four screenshots taken from different distances. Notice the model breaking up into scattered transparent segments.

This shot is a good, normal view from a reasonable distance.



As we get just a bit closer, notice the left landing bay has now lost part of its wall opacity and the opposite hub has now become partly transparent so that you can see through its solid wall and into its back landing bay.



Shot 3 is taken just a tiny bit closer. Now, the former panels that were erroneously transparent are now opaque, but new wall sections have become transparent.



Shot 4 is a final view, showing the effect continuing.



I love Celestia's ability to draw these complex and beautiful models and this bug is really scary. This is happening to at least 10 of the real/fictional models, meshes and spacecraft models that I have viewed in 1.3.2pre 10. I use these models extensively in my educational activities (one Activity has 28 models alone). Chris, PLEASE fix this. I wish I could help you, but I know nothing about coding.

Thanks in advance. Let me know if I can assist in any other way.

Frank

[fsgregs]

Chris et al:

Here is another model mesh showing the same transparency breakup effect. Three screenshots are included. The first is normal view. The other two show different parts of the model becoming transparent as you move in closer.







Obviously, this bug results in the entire model losing its high quality and becoming "defective" as viewers try to enjoy it. It really needs to be fixed.

Thanks as always for your tireless work.

Frank