Selden's Galaxy map with sprites

[SkyScraper]

This screenshot is based on Selden's Galaxy_map addon

http://www.lepp.cornell.edu/~seb/celestia/files/galaxy_map.zip

I just replaced the 3d sphere models of nebulae (hii.cmod) with a red sprite and molecular clouds (co.cmod) with a green sprite

Here is the sprite definition:

Code: Select all

#celmodel__ascii
material
diffuse 0 1 0
texture0 "blob.jpg"
blend add
end_material

mesh
vertexdesc
position f3
pointsize f1
end_vertexdesc

vertices 1
1 0 0 0.25 

sprites 0 1
0

end_mesh


you also need the texture "blob.jpg" i got it from this addon:
http://www.shatters.net/~claurel/celestia/files/spriteneb.zip

[Cham]

Haa ! Good one. You're taking advances on me. I'm stuck because the sprites aren't working on the Mac

Mathematica is waiting, because of this. I'm so extremely frustrated with this situation, since I could create an infinite set of fluffy accretion disks, nebulae, and other fantastic models for Celestia. DAMN !

[SkyScraper]

I just love the additive blending effect:

I made no modifications to the dsc declaration and the FOV is the default value

[Cham]

Is there any depth sorting problems with this rendering ? Can you feel the farthest blob *behind* the close ones ?

[SkyScraper]

Is there any depth sorting problems with this rendering ?

I can not identify any problem, i dont see it from a programmer's perspective

Can you feel the farthest blob *behind* the close ones ?

Not realy, all of them have the same opacity and when the sprites get one in front of another they look like they are mellting together

[Cham]

So there's a depth sorting problem with the blobs.

My nebulae project with Mathematica is then killed, once again !

[SkyScraper]

I think thet if you add a different texture instead of a blured dot
Or by making the nebulae fully opaque you can get the result you want

EDIT
Only the blobs with exactly the same color and opacity melt together

[selden]

Cham,

The "melt together" appearance is not a depth sorting problem. That's what translucent point sprites are supposed to do, so one can use a "particle system" of many point sprites to implement fog and clouds of smoke, for example.

If one uses fully opaque point sprites, ssc Mesh objects defined using them are properly depth sorted.