Emmisive true conundrum

buggs_moran · Post #1by **buggs_moran** » 26.01.2006, 03:09

I am working on one of my addons. It is a close binary with an accretion disk. (Pay no attention to the chunky quality, it's nowhere near the beta stage yet. :wink:

) Anyway, I turned off Emissive True for the disk. It is orbiting the primary (the star filling it's Roche Lobe). I can't figure out why the lighting is so far off. I would've thought the side towards the primary would be illuminated at all times...Help.

Cham · Post #2by **Cham** » 26.01.2006, 04:46

What graphics path are you using ?

How many stars are there ?

buggs_moran · Post #3by **buggs_moran** » 26.01.2006, 12:23

I'll let on to my ignorance here Cham, what do you mean by graphics path? I designed the disk in Anim8or ported to 3ds then to cmod. The texture is a png. Diffuse is set around .75 .75 .75 and I have a small specular set for some highlighting. The primary (A) and companion (B) stars are just built in an stc. There are four other companions, but all are more than 700 AU's out and are not situated so that they would shine on the disk. All six orbit a common barycenter roughly 1/3 of the distance to B from A. I assume the disk is being illuminated from within by B somehow. Originally I had the disk orbiting B and thought that was the problem so I set up the orbit around A. Same problem... The reference planets I put around most of my stars seem to be illuminated correctly by both stars.

Post #4by **selden** » 26.01.2006, 12:52

Buggs,

I think Cham meant to ask
"Which of Celestia's Render Paths have you selected?"

The older paths can only draw shadows from one or two light sources. The OpenGL 2.0 path can draw shadows caused by as many as 4 light sources.

Remember, though, that 3D Mesh objects don't (yet?) actually cast shadows or can have shadows cast on them. Their surfaces are only shaded depending on the directions toward the light sources.

buggs_moran · Post #5by **buggs_moran** » 26.01.2006, 13:44

Ah, duh, crud. I'll have to try when I get home from work tonight (T -9 hours, really have to get that VNC set up). Still, there is no light source in the direction that the disk is showing... I am also going to try to offset the disks mean anomaly to see if the light is from B.

buggs_moran · Post #6by **buggs_moran** » 27.01.2006, 00:52

Okay, tried all the render paths to no avail. Also tried adding two other disks at 3 o'clock and 9 o'clock in the image below. They render fine in all paths, light and shadow from both stars. So my issue is an artifact of the disk having the secondary star at it's center. I really am trying to keep reality (well you know Celestriality) here. The secondary is an A8 star and I want users to be able to click on it for info. Any ideas?

buggs_moran · Post #7by **buggs_moran** » 29.01.2006, 01:36

In an effort to get this post noticed again. Help.

Cham · Post #8by **Cham** » 29.01.2006, 01:42

I think this is a bug.

If I remember correctly, I've experienced something similar in the past, in my numerous experimentations about nebulaes and black holes.

If you set your object as an emissive one, your problem should disappear.

buggs_moran · Post #9by **buggs_moran** » 29.01.2006, 04:11

It does, but that kills the idea. :cry:

I think I'll move this to the bug list then. Thanks.