Display problem with some Spacecraft-nVidia GeForce2 Go

General discussion about Celestia that doesn't fit into other forums.
Topic author
DOJOMO
Posts: 49
Joined: 10.08.2005
With us: 19 years 3 months

Display problem with some Spacecraft-nVidia GeForce2 Go

Post #1by DOJOMO » 10.08.2005, 20:25

I have a 3 year old Dell Inspiron 8200 Laptop with Intel Pentium 4m 1.6gz, 256 mb Ram. Windows XP Home
nVidia GeForce2 Go 32 mb memory Graphics. 4.4.8.2 Driver. The Forceware universal driver is not recognized.
Direct x 9.0c.

Celestia 1.3.2 - and it is brilliant.

I know the machine is a bit dated but it works ok and I really cannot afford a new one just now. When displaying some Spacecraft in Celestia, Hubble, ISS and MIR display perfectly but Cassini (Hugyens is OK on its own), NEAR, and an add of Cassini do not . All these display with what looks like broken fragments of opaque glass projecting out of the Spacecraft, mainly from one side and which alter as the Spacecraft is rotated. In wire frame the image seems complete but lines project out of the model in an odd way.
At first I thought it might be problem with the Graphics Card memory but with ISS displaying ok and all of the spacecraft displaying in Anm8or I am less sure.

I have tried the following:-
1 Turning off as many of the memory hungry features as possible.
2 16 rather than 32 colours.
3 Whole screen.
4 Small Window.
All these had no effect.
5 I imported Cassini.3ds into anim8or where it displayed ok and reexported it in 3ds format hoping this might correct any faults. Celestia still displsyed it incorrectly. (I created some simple models in anim8or but noticed that a sphere cut in half was transparent from the inside when viewed in Celestia)
6 In Windows Graphics Hardware Troubleshooter I lowered the acceleration to the lowest but one setting. This did correct the faulty display although the colour on the faces of the model was not shown. However the display was very slow.

Having searched the web as thoroughly as I can I found only one reference in the motherload which suggested a problem with the Z coordinates being incorrectly signed. The image does seem to to have something like this.

Does anyone have any solutions. If a fix is possible that would enhance what is in any case a fantastic program. If not a simple explanation for a computer illiterate would be most welcome.

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selden
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Post #2by selden » 10.08.2005, 20:58

noticed that a sphere cut in half was transparent from the inside when viewed in Celestia
That's as it should be. Celestia only draws polygons that have their surface normals pointing toward the viewpoint. The surface normals of a sphere only point outward. When viewed from the inside, they all point away from the viewpoint. You can make a sphere opaque from the inside if you flip its normals. That's an option in Anim8or's Edit menu.

Sorry, I can't help with the "broken glass" symptoms, though. (Those symptoms aren't visible on the Nvidia graphics cards that I've used.) Have you looked on Dell's site for updated drivers?
Selden

Topic author
DOJOMO
Posts: 49
Joined: 10.08.2005
With us: 19 years 3 months

Post #3by DOJOMO » 10.08.2005, 22:14

Thanks for the response. I wondered if the Z aspect was somehow connected with the problem as the image is complete but with these strange flat plane protrusions.
As regards the driver it is in fact from Dell and they have confirmed that it is the latest driver. I am not totally convinced that they correct as searching the Web I have found reference to a version 5.6.7.3 but I cannot find it anywhere including nVidia.
Thanks again.


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