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View Full Version : Is subsurface scattering very hard to implement?



lw3d23
01-18-2005, 02:12 PM
Is subsurface scattering very hard to implement, perhaps they (the developers) were very busy at those new aa features. LW 8.2 still doesn't have SSS, someone said the raytracing functions of LWSDK need to be improved, but I don't see any improvement about raytracing functions.
When can we get this? Sigh... I don't want to use other 3d software just b'cos of SSS. I hope newtek will add this common feature in next version.

p.s I have tried G2, it might be due to the limitation of LWSDK, but the fact is its SSS is really not that good. Compared with Brazil and Mental ray, their SSS are much more impressive.

Panikos
01-18-2005, 09:01 PM
I guess you saw some images from top-artists of Brazil / Mental Ray.
How much time you spent on G2 ?
I am quite satisfied with it.

;)

lw3d23
01-19-2005, 08:11 AM
I guess you saw some images from top-artists of Brazil / Mental Ray.
How much time you spent on G2 ?
I am quite satisfied with it.

;)

Not only top artisits, many users showed their images with impressive SSS.
I used G2 since the first version of G2. I have spent so much time on G2 SSS, but I could not get a good result. especially the radiosity is on.
Unfortunately, I have not seen any impressive image with g2s SSS by any LW artist. I would love to see if you know any good LW artist who did a good job with G2 SSS. ;)

oDDity
01-19-2005, 08:50 AM
And G2 sss doesn't work proprerly with area lights either. Being reduced to working with spotlights is really scraping the bottom of the barrel.

Panikos
01-19-2005, 09:13 AM
Yes, Area lights & G2 is a problematic Combo.
But ...
here are some images I did

pooby
01-19-2005, 09:36 AM
And G2 sss doesn't work proprerly with area lights either. Being reduced to working with spotlights is really scraping the bottom of the barrel.

But Point arrays will do the same job and work fine..

lw3d23
01-19-2005, 09:42 AM
But Point arrays will do the same job and work fine..

how many point light did you use for 1 light source?

pooby
01-19-2005, 10:03 AM
I used about 20 parented to a spinning null with motion blur on and low antialiasing.

If you set up a light array with sliders to affect brightness and colour, then you can save that scene out and just import it whenever you need an 'area light'.

It has other advantages to an area light too. you can turn off specularity for some of the points, thus being able to control the overall specular effect of the light array.
Plus is doesnt have that weird dark spot at the edge like an area light has.

It also has no noise at all..

lw3d23
01-19-2005, 10:11 AM
I used about 20 parented to a spinning null with motion blur on and low antialiasing.

If you set up a light array with sliders to affect brightness and colour, then you can save that scene out and just import it whenever you need an 'area light'.

It has other advantages to an area light too. you can turn off specularity for some of the points, thus being able to control the overall specular effect of the light array.
Plus is doesnt have that weird dark spot at the edge like an area light has.

It also has no noise at all..

Why motion blur is on?
Can you post capture a screenshot that how your lighting setup look likes, if you don't mind?
thanks a lot

pooby
01-19-2005, 11:07 AM
The motion blur smooths the array out to avoid sharp edges and artefacts.. that's why you have the spinning null..
If you didn't have motion blur, you would need 5 times the amount of points

Kvaalen
01-19-2005, 11:17 AM
Why motion blur is on?
Can you post capture a screenshot that how your lighting setup look likes, if you don't mind?
thanks a lotIt's the famous spinning lights trick. A quick google search should find tons of info about it. :)

pooby
01-19-2005, 01:16 PM
It's not the standard spinning lights trick though.. That uses a shadow map spotlight as I recall.. this is a bunch of points, but the basic theory is the same.

lw3d23
01-19-2005, 08:17 PM
It's the famous spinning lights trick. A quick google search should find tons of info about it. :)
I know the common trick, but I gues the trick that pooby using is a bit different than the common spinning lights.

Ztreem
01-22-2005, 08:11 AM
I use a similar setup with pointlights to get softshadows. But I don't use the spinning light trick, I use shadow noise reduction to get rid of the banding in the shadows. You can check this thread out, I also share a setup there.

Ztreem
01-22-2005, 08:12 AM
Ok, forgot to submit the link.
http://www.spinquad.com/forums/showthread.php?t=4124&highlight=softshadow

Kvaalen
01-22-2005, 04:09 PM
It's not the standard spinning lights trick though.. That uses a shadow map spotlight as I recall.. this is a bunch of points, but the basic theory is the same.I didn't think the "spinning lights trick" was restricted to one kind of light only and otherwise is not called that... :)
I know that the original tutorial that introduced it to most of us called the trick that and used spot lights, but I've since seen it used many times just for the trick of having lights spinning/moving and using motion blur on them.

I usually use that trick with point lights and I've always called it that. :\

pooby
01-22-2005, 04:24 PM
Of course, any sort of system that use lights that spin is going to be a spinning light technique but I didn't want them looking up 'spinning light trick' and getting confused because it was probably a setup which wouldn't help G2.