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hikaru78
12-29-2005, 05:55 PM
whenever i scale the attenuation on an omni light, i'll get strange jaggy shadowing artifacts on my lit objects, but everything looks fine when i scale the lights back to 100. i tried switching shadows on and off, along with the attenuation controls and shadow controls. ive searched around the threads to see if anyone else have had similar problems but couldnt find anything. i was wondering if this was a common thing within max. any type of feedback would be appreciated. thanks
JohnnyRandom
12-29-2005, 06:06 PM
sorry, edit, read it more closely...

Are you using a shadow map? sounds like your using one, in the shadow map parameters...leave the bias alone, try increasing the map size in computer friendly numders like 512, 1024, 2048, ect. Increasing sample range will soften edges.
hikaru78
12-29-2005, 06:12 PM
i want to scale the attenuation so that i can manipulate the light like you would with an area light in maya. to be more specific, im trying to light an interior and i want to use just one omni light to light the room by scaling the attuention to fit the size of the room....as opposed to using multiple lights. hope that makes more sense
JohnnyRandom
12-29-2005, 06:25 PM
the far attenuation?
soulburn3d
12-29-2005, 06:39 PM
Are you talking about actually scaling the light, like using the scale function? or just increasing the value of the far attenuation of the light? Could you maybe post a diagram or screenshot of what you're trying to do?

- Neil
Teriander
12-29-2005, 06:50 PM
He's talking about this (view the image attachment). Scaling the omni itself so it only effects a certain lengh and a small height.
JohnnyRandom
12-29-2005, 07:25 PM
I understand.

Tested with shadow map and resulting shadows leave blocky edges at defualt settings, tested with map size of 2048 and they start to deminish.

tested with ray-traced and virtually gone.

tested with no shadows no blocky artifacts.

All Default Scanline

First image Defualt Omni w/ defualt shadow map.
http://img506.imageshack.us/img506/5276/default6ta.png

Scaled 200% X&Y, 50% Z scale shadow map size 512 (artifacts at the shadow edge of the sphere)
http://img520.imageshack.us/img520/4848/50zreduce20qq.png

Same with ray-traced shadows (artifacts gone)
http://img520.imageshack.us/img520/8176/raytraced3uj.png

Not sure what to say... ??? don't scale it as much, use ray-traced shadows instead of a shadow map...
DerPapa
12-29-2005, 09:31 PM
confirm that!

Must be a bug. I'm 100% sure it worked with older max versions (I used it a lot for lighting our "runtime" clip, done in max 4.2)
But I had the same error with max 8. dunno what about version 5-7.

Michael
Teriander
12-29-2005, 10:05 PM
Version 7 is what hikaru78 (member.php?u=73162) and I use. Both have the same problem. But looks like Ray-Traced shadows is the cleanest bet.
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