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Dark Asteroid Texture

Posted: 06.08.2002, 14:27
by Troy
The title says it all. This is the standard asteroid texture, but with reduced brightness and a quick gaussian blur to remove some artifacts from the original. This texture is highly useful for Neptune's dark, "sootlike" inner moons: Proteus, Larissa, Galatea, Despina, Thalassa, and Naiad.

Any body you assign this texture to should also have a dark color entry in your ssc file. For example:

Code: Select all

"Proteus" "Sol/Neptune"
{
   Mesh        "proteus.3ds"
   Texture     "darkasteroid.jpg"
   [b]Color      [ 0.4 0.4 0.4 ][/b]
   Radius      218

   EllipticalOrbit
   {
   Period      1.122315
   SemiMajorAxis   117647
   Eccentricity   0.0004
   Inclination      0.55
   MeanAnomaly   310
   }

   Albedo      0.06
}


Enjoy! http://webpages.charter.net/myrkwood/celestia/darkasteroid.jpg

Posted: 06.08.2002, 14:41
by Sum0
What a coincidence... I made a brighter ice asteroid texture...

Posted: 06.08.2002, 14:45
by Troy
Heh, I sense an asteroid texture pack in our future. :wink:

Posted: 06.08.2002, 19:07
by Rassilon
Blendtexture true comes in handy when used hand in hand with Color...Can be used to colorize only...tho darkening might work...

Posted: 07.08.2002, 17:10
by Troy
Rassilon wrote:Blendtexture true comes in handy when used hand in hand with Color...Can be used to colorize only...tho darkening might work...


You're right, thanks for the tip. It does work for darkening the texture, although it has raised some questions / issues:

- What is the preformance hit for using the BlendTexture function? Clearly it wouldn't be much on a small texture like asteroid.jpg, but what about larger textures?

- Is there a paticular reason the ssc keys are case sensitive? I understand this is the default under linux development, but when dealing with files that are hand-edited by non-programmers, it would be better if we removed case-sensitivity.

- The following line is BAD:

Code: Select all

BlendTexture TRUE


When Celestia reads the all-caps 'TRUE' value, it quits reading the ssc file. This means that the rest of the objects do not get loaded. This happens silently, meaning that Celestia does not print an error message. Of course, fixing the case-sensitivity issue will fix this as well.

Hope this helps someone out. :)

Posted: 07.08.2002, 19:02
by Rassilon
Well in the case of C programming if chris set up his variables like:

boolean {"true","false"};

then the boolean identifier would have to be lower case or the software would crash or the line ignored...

Posted: 07.08.2002, 19:28
by chris
Troy wrote:
Rassilon wrote:Blendtexture true comes in handy when used hand in hand with Color...Can be used to colorize only...tho darkening might work...

You're right, thanks for the tip. It does work for darkening the texture, although it has raised some questions / issues:

- What is the preformance hit for using the BlendTexture function? Clearly it wouldn't be much on a small texture like asteroid.jpg, but what about larger textures?
There's no performance hit whatsoever with BlendTexture on any 3D graphics hardware that you can run Celestia on.

Troy wrote:- Is there a paticular reason the ssc keys are case sensitive? I understand this is the default under linux development, but when dealing with files that are hand-edited by non-programmers, it would be better if we removed case-sensitivity.


This is an oversight that I've never gotten around to fixing. I should be able to do something about it for 1.2.5.

--Chris