3delight tests

[Mathaeus]

I've already posted some point-based hair renders in this thread, but for these, I've hacked appropriate sl files to get it properly - now it's available for everyone. Generally, point-based approach seems to be much slower (even I didn't bothered that much with tweaking of this).

Only for hairs and a white lambert on character, mentioned setup renders in about five minutes with 2 core 3delight, on 1536x2048, together with shadow map generation. BTW that's a lighting setup for entire character. For hair only, I'd would go with much less than 20, having a much more room to avoid the flicker.

What I didn't want to bother people at Area, it's a huge influence of hair density, ways of interpolation, that only ICE can handle effectively. Especially for short hair-fur, not big deal to create some kind of signed distance field, or shading transfer entirely with ICE. Unfortunately, I didn't found a way for packing that 'ICE lighting' in ready-to-use public compound.

afaik, there is much more to come (even for SI users ), related to hair/fur in 3delight, but I think there is no sense to talk about in advance.

cheers

[j3st3r]

Hey Mathaeus.,

That looks really awesome. Can you tell me how did you set up SSS? For me it doesn't want to work, there's a quite large difference between MR's SSS and 3delight SSS. I figured out that it's some kind of issue with scaling, but not sure

[Mathaeus]

Hey Mathaeus.,

That looks really awesome. Can you tell me how did you set up SSS? For me it doesn't want to work, there's a quite large difference between MR's SSS and 3delight SSS. I figured out that it's some kind of issue with scaling, but not sure

Hi Jester,

I know you know this, 3delight just emulates the mi_sss_fast stuff, internally that's a different shader, with ability to do a color variance by itself. If you'll get the same result in every condition, that would be miracle, I think.
How does it match the scaling of subsurface effect, it seems it's defined in "misss_fast_shader.sl" in RSL folder (I know you're coder too ).
You'll find the code about scaling somewhere after "uniform float scale = i_scale;"... Before this, there's what shader is doing in subsurface precomputing phase ....., after this, there are subsurface scattering parameters.

What final result (in 3delight) you'll want for for human skin at 1SI Unit= 10cm, it seems to be something around 0.012 - 0.016. I got this value from hillybilly test by xsi base member kissb, it worked nicely for me too.

For this image, I've used something from my kitchen, what you'll already get by applying a 3dl subsurface attributes to object with any standard XSI shader, but with two modifications: shading in precomputing phase is changed to 'all direction' ( Nn instead of default Nf), and ability to multiply the scattering by color/texture. As it is for now, it looks like a good old Diffusion or Md SubScatter - just one layer, back-scattering is not so pronounced. Preset is "Skin2". Even it works nicely, I have no idea does it cause problems somewhere else.

Cheers

[j3st3r]

Thanks Mathaeus,

I still struggle with it, for some reasons, playing with the SSS parameters seems to produce bit "unpredictable" results...Interesting that using the fast skin seems to be OK is, but again, the scale issue...But the hair rendering, is sooo nice in 3dl, so I'll try my best to figure out a proper sss to me...

[j3st3r]

Hey Mathaeus,

How do you render eyes? The usual setup seems to be not working, I used to have a separate object for the cornea, with transparency and reflection, and an object for the white part and iris, etc. Now when I render it, it's black...

[Mathaeus]

Hey Mathaeus,

How do you render eyes? The usual setup seems to be not working, I used to have a separate object for the cornea, with transparency and reflection, and an object for the white part and iris, etc. Now when I render it, it's black...

Separate objects, no shadow casting for both.
What you posted on 3dl forums, looks like too high ray trace bias. Default is 0.01, I think. You could set this to 0.001. Once shadows will come, you'll probably want to apply the 'hit mode' property, set this to 'use material for shadow ray', plug something into shadow port. For deep shadow maps, appropriate option in global render options.

[j3st3r]

Thanks for the tips, I've tried them, but no success...seems that 3.0.8 is buggy a bit

[ActionArt]

now a shameless plug (but somehow I'm not sure how many SI-community visits the Area too ) - latest image is on Area front page for a while.

Congrats on that! Well deserved!

[caledonian_tartan]

just as a late question:

what are deep shadow maps?
is it the same like shadow maps, which are in the rendersettings?

[rray]

Good job!


Shadow map = 2 color-only shadow map, no transparency
Deep shadow map = Pixar's original "with tranparency" shadow map format (pdf)
Detail shadow map = mental image's version of deep shadow maps
Volume shadow map = Softimage's GUI name for MR detail shadow map

[caledonian_tartan]

hey thanks! (and good job too for the area post!)
i don't find a way to activate deep shadow maps in 3delight...
it should be possible, but i don't find something in the docs nor the ppg of 3delights render settings...

using the maps in the shadow maps tab renders for ages...

[Mathaeus]

i don't find a way to activate deep shadow maps in 3delight...
it should be possible, but i don't find something in the docs nor the ppg of 3delights render settings...

Hi,

you enable the deep shadow maps in the same way as with Mental Ray, in Shadow Map tab of light's PPG. For colored deep shadow map, procedure is:
1: in global render options, under Shadow Maps, enable 'Surface' for shadow map shaders
2: apply a 3delight's 'Hit Mode' property to object or group, set 'Run Material' for Shadow Rays
3: put something into the shadow slot in rendertree, let's say Color_Save_State, or Constant material.

cheers

[TwinSnakes007]

I'm really having a hard time getting my head around 3Delight rendering. Are there any tutorials or can someone provide a scene I can study?

Thanks.

[Hirazi Blue]

There is an older tutorial series made by "Chinny" (Jason Brynford-Jones) from Softimage, but he uses XSI 6.5 and an older version of 3Delight for Softimage as well. Still worth watching as a basic introduction IMHO
;)

[jgjones]

CSG

This is a render-time CSG ( constructive solid geometry, Boolean operations ).

Speaking of CSG... anyone know if there is a trick to getting it to work right, beyond the description in the user manual? When I set up a simple test, with two intersecting spheres, (sphere B has the 3Delight CSG property, set to subtract, and is a child of sphere A), the "cut" surface will only respond to ambient light (no shading), and is controlled by sphere B's material.

I'm using SI 2012 SP1 (64-bit) and 3Delight 3.0.11

-Jim

[Mathaeus]

Speaking of CSG... anyone know if there is a trick to getting it to work right, beyond the description in the user manual? When I set up a simple test, with two intersecting spheres, (sphere B has the 3Delight CSG property, set to subtract, and is a child of sphere A), the "cut" surface will only respond to ambient light (no shading), and is controlled by sphere B's material.

I'm using SI 2012 SP1 (64-bit) and 3Delight 3.0.11

-Jim

Hi,

as far as I can recall (didn't played with CSG since this scene), setting XSI geo approx to more than zero, or using a Renderman subdivs ( 'smooth subdivision threshold' on zero), made it to work as expected.
Anyway, here is the thread in 3delight forum, about CSG and related stuff. There is also a link to XSI model I've created for these CSG renders.


cheers