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jigen08
09-02-2010, 11:11 PM
I just upgraded to Maya 2011 from Maya 8.5. Previously I was able to create render passes by following these steps:
1) create a new render layer, add objects
2) under render layer, go to presets > occlusion

Maya 2011 doesn't seem to have the presets function under render layers. (Has it been eliminated?) I thought it might be under: Add New Render Pass > Ambient Occlusion, but no success. The image looks the same as the beauty pass. Mental Ray is selected.

Anyone able to get an occlusion pass in Maya 2011? I tried searching online, but everything I came up with seemed to be for older versions of Maya and dealt with adding shaders, etc. If you've seen a tutorial for this in Maya 2011, could you post the link?

Thanks in advance....

Galakgorr
09-02-2010, 11:47 PM
right-click the layer, go to attributes, then use the presets button and select occlusion.

or, just do it manually-- create a surface shader and an mib_amb_occlusion texture, assign mib_amb_occlusion as the surface shader's out color, then assign this new shader as the material override for your render layer. it's really that easy.

InfernalDarkness
09-03-2010, 05:00 AM
Hello Galakgorr,
Would this method also take into account a "cutout opacity" file node from a mia_x, for example? If not, how would such a factor be done? I'm new to AO in general, but always just use it in my main renders and not in a separate pass... Love to learn how to make passes work...

tkdmatt
09-03-2010, 05:22 AM
You won't use mia's with Galakgorr's method. What I do when I need transparency and/or displacement is to make surface shaders for each of my objects with applied trans/displacement and the mib_occlusion node linked into all of them, all applied on a render layer instead of using the layer override.

MasonDoran
09-03-2010, 08:52 AM
yeah....the preset method assigns a single surface shader to the entire render layer, so you will lose all of your bumps, transparency, and displacements. To get all of that back, you would need to build the shaders by hand.

It would actually be easier to use the Framebuffer method, although the results are different.

jigen08
09-03-2010, 12:42 PM
Thanks Galakgorr, much appreciated.

Changes like this are subtle, and probably a good argument for upgrading every year to keep up with (I don't know if the change happened in 2009, 2010, or 2011, so searching help forums becomes a bigger haystack). Now if only I could convince my wallet of the need to stay current...

jigen08
09-03-2010, 12:49 PM
I should add...

I posted this exact question on the Autodesk Discussion Group forums (part of my Autodesk subscription, that also includes some nice outdated DVD downloads and a dearth of technical support). Several views, no replies.

My last subscription had a forum that had Autodesk tech contribution. I would caution and advise against the subscription. They offer less support than a half-tied hammock.

Galakgorr
09-09-2010, 03:08 AM
Hello Galakgorr,
Would this method also take into account a "cutout opacity" file node from a mia_x, for example? If not, how would such a factor be done? I'm new to AO in general, but always just use it in my main renders and not in a separate pass... Love to learn how to make passes work...

unfortunately that wouldn't work unless you built a unique AO shader for each material that has cutout opacity. same thing for displacement. i've had to do this for several jobs in the past... for every material with displacement or cutout opacity, i make a new surface shader (or mia_material_x, it really doesn't matter) and turn it completely black, apply the same cutout opacity map / displacement map as the original has, and then assign that material to the appropriate objects on the new layer. it's not exactly the most elegant method but it works... you could do this for a z-depth pass as well.

if you wanted to try using the passes system instead of using a new render layer, you could use a writeToColorBuffer with the AO texture plugged into the "color" slot of the writeToColor. then create a custom color pass, and link the buffer to the appropriate pass. this will respect displacement, but i'm not sure if it will respect cutout opacity. it also has the potential to slow down your render quite a bit, some kind of bug with mental ray custom buffers that's been a pain in the ass for years.

chafouin
09-09-2010, 08:17 AM
I'm not sure about what I'm going to say because I haven't tried it yet, but what about using the mia_material ambient occlusion, and then render with the occlusion pass?
I guess it works with displacement, bumps and transparency, and it's correctly calculated (just need to multiply it with your beauty, instead of multiplying it with your diffuse pass).

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09-09-2010, 08:17 AM
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