Hi all,
this time, a bit more about 'hair translucency' effect, especially noticeable on bright hairs. One simple method to get this effect is using of colored shadows.
That's how my trial looks like:
For 1280x1280, 2-core 3delight took about 8 minutes for render. There is 80k hairs, two spot lights with 1024 deep shadow maps. I've used only standard XSI shaders.
Take look at
full res.
So how to get this in 3delight:
1: In global render options, under 'Shadow Maps > Shadow Map Shaders', enable 'Surface'.
2: Apply 3delight's 'Hit Mode' property, to Point Cloud with ICE strands.
3: In 'Hit Mode' property, enable 'Run Material' for Shadow Rays.
4: Enable 'Detailed Shadow Map' for your lights.
Step 3 is needed, because XSI Hair Shader doesn't allow colored shadows, even it can be used as a shadow shader. That's how it looks like when XSI Hair Shader is used for shadows too (on left side
).
So, we will supply another shader for shadows. Some recipe is a bit darker and more saturated color for Constant surface, some gray variance for transparency. Basic render tree looks like this one:
And that's all.
Tips:
Somewhere in installation folder, probably \Softimage\.....\Data\DSPresets\Materials\Hair, there is a lot of color presets for XSI Hair Shader. I've found them *very* usable.
Here I've used a 'Hair Golden Blonde'.
When rendering ICE strand segments, 3delight automatically does the curve interpolation. Generally, you should be able to use a much lower count of strand segments.
About mip-mapping for Deep Shadow Maps, it seems 3delight adjusts this automatically. Corresponding 'Sub-Samples' parameter seems it has no effect, even it's mentioned in the docs. On the other side, by watching render log, I've noticed reports about various mip-map levels. In short, I believe in 'common' rendering strategy - start with low-res DSM, but don't hesitate to increase it if needed.
Cheers