ATI - The old problem

holydave · Post #1by **holydave** » 24.11.2005, 22:36

Hi guys
Ive got a Radeon 9600XT (256mb VRAM), and after gawping at that pic of some space station over Florida, I downloaded Celestia and found the earth to be a bluey-greeny mess, even with everything turned up to 11.
I'm sure I've posted something like this before, but I'll continue nonthless.
Does anyone have any suggestions of any way I could get Celestia to look like it does on the site with a Radeon? I really don't want to go and buy a GeForce, see.
Any help would be much appreciated.
Oh, and by the way, the bump-mapping works on the moon, but the textures just aren't good at all.

Malenfant · Post #2by **Malenfant** » 24.11.2005, 22:39

You sure you're not set at low-res textures? Try pressing Shift-R a couple of times, at least til you're on Medium Resolution if you're not already.

And try cycling through the render paths. Ctrl-V I think is the command to do that - you want to be in the best one possible.

holydave · Post #3by **holydave** » 24.11.2005, 22:45

No, ive tried that already
Thanks anyway though mate.

Malenfant · Post #4by **Malenfant** » 24.11.2005, 23:45

holydave wrote:No, ive tried that already
Thanks anyway though mate.

Though I'd ask the obvious first

. Can you post any screenshots to show us what's going on?

Fightspit · Post #5by **Fightspit** » 25.11.2005, 08:10

holydave wrote:Goddam DirectX

Celestia use OpenGl not DirectX.

holydave · Post #6by **holydave** » 25.11.2005, 11:32

Yes, fightspit, I realised that.

Here's some screenies:

The Hubble over West Africa:

Florida:

British Isles:

Phobos and Mars, similar to the shot on the website for comparison:

All these screenshots taken on full texture settings and with all the OpenGL titbits like specular lighting and bumpmapping (But sadly not many textures)

Any help would be much appreciated
DAVE

Post #7by **selden** » 25.11.2005, 13:16

You are just seeing the limitations of the surface texture images that are included with Celestia.

The surface texture image map for the Earth is 2Kx1K. This means that each individual pixel of the Earth's texture has to represent a region on the surface that's about 20KM on a side.

If you want to be able to see high resolution images of a planet's surface, you have to install a Virtual Texture surface map. Some are available on the MotherLode. http://www.celestiamotherlode.net/

holydave · Post #8by **holydave** » 25.11.2005, 13:26

Thanks for the reply Selden mate.

But look at the shot of the Hubble. Is it like that on everyone else's system? I mean, the shot at the top of the homepage of the website is, i assume, of the hubble, and it looks spectacular (and specular, for that matter).

And I remember reading somewhere (I think in one of Selden's posts) that the Radeon cards, even above 9500, cannot draw textures over 2Kx1K. My first post was really about trying to overcome this limitation.

Are the shots on the website just custom skins?

Thanks
DAVE

Post #9by **selden** » 25.11.2005, 14:21

Dave,

The picture of the Hubble that's on the Celestia web site on Shatters was created using both an Addon that contains an extremely high resolution model of the telescope and a VT surface texture for the Earth. The Hubble model is available on the spacecraft page of the Celestia MotherLode site. VTs of the Earth are available on their Earth page. (Unfortunately, however, ibiblio, the hosting site, seems to be down right now.)

Celestia automatically cuts up the surface texture maps that are applied to its internal spherical models of planets. As a result, you can use surface textures for planets that are as large as will fit into your system's main memory. Textures that are larger than your system's main memory (RAM) should just cause your system to run extremely slowly (as much as several minutes per refresh) as it pages them between main memory and disk.

VTs try to get around this performance problem. They consist of many small image files instead of one large one.