personal important maya question
 

I don't know how I can explain this but my problem is that in my maya animations, I want to put some compositing effects behind front objects but in front of rear objects.
heres a pic:
http://img238.imageshack.us/img238/8547/punchre0.th.jpg

I could just do a layer render while hide everything but the guy in front but the problem with that is that I don't get the shadow casts from other objects or the correct lighting. is there any posible way to get the exact correct renders but in multiple layers? thanks

Yeah, I can think of a way to do it, you'd just need to render the sequence twice.

#1) Render out whole sequence to tga stills
#2) Render out just the guy at the front in the chair - no need to worry about image quality for this part, we just want the alpha mask of his outline.

Then you could use the alpha channel from #2 to mask the special effect, and prevent it from appearing where the guy in the chair is. And there you have it, your effect appears in front of the guy swinging the punch, but is masked and so doens't cover the guy in the chair, thus appearing to be an effect between the two of them in 3d-space.

I don't use any decent compositing software, but I'm guessin that AE would do it(?)

Simon.

if you put just the guy in a separate render layer you shouldn't need to hide anything... choosing the render layer you put him in usually makes everything else invisible in your viewport automatically... and hiding things is probably what is preventing you from getting the proper render.

enhzflep: yea AE can do it, and pretty easily too. when you import footage files it asks you how to treat the alpha each time. you can ignore it, treat it as normal, treat it as pre-multiplied, etc.

You can set the forward character to be a "black hole" in the render, do a search in the help files for black hole as I cant remember where it is (think its in the attributes for the material something like ambient something or other, not got maya open to have a look)

This would be the preferable way to do it, epsecially if you want a CG object to go behind a real object on a plate

Alrighty then!

Thanks for that NeoStrider, you've just answered a couple of things for me. I've got a miniscule understanding of render layers, and that's given me food for thought.

I'm going to have to get off my backside and get AE methinks, thanks for the tidbit.

EDIT: Gster: What a goldmine of info, I'll have to remember that, taa. Thanx for the tip on RF too, got the claret flowing into a glass now.
Hmmm, where's my explosives... It's just a shame about that 10 minute reminder screen huh?, gad dammit. ;)

S.

Just upgraded from Maya 6 to 8.5, so prior to getting my new maya, I didnt have a plug in for realflow for 6.0 (as they only went as far back as 6.5) and not on 8.5 theres no plug in available yet!


P.S I found lots of realflow vids on there site too.

great I learned a lot. I never knee there was render layers next to display but its great that I can see it now. Ill have to try the AE masking as well the concept seems to be a great idea.