Maya AO maps
polycounter lvl 18
OK, what gives?
I get this beautiful clean result out of XSI on the left, but no matter what I tweak in transfer maps, this nasty blown out pos on the right outta maya.
We currently only have one XSI license and it aint on my machine so its a pain. So, until we get more, does anyone have any tips on how to get a better result out of Maya? I mean it's essentially the same renderer in theory, right?
Any help appreciated, maybe I'm missing something obvious here.
I get this beautiful clean result out of XSI on the left, but no matter what I tweak in transfer maps, this nasty blown out pos on the right outta maya.
We currently only have one XSI license and it aint on my machine so its a pain. So, until we get more, does anyone have any tips on how to get a better result out of Maya? I mean it's essentially the same renderer in theory, right?
Any help appreciated, maybe I'm missing something obvious here.
Replies
In Maya transfer maps you pretty much only have these options to fuck with:
File format
Bits per channel
Occlusion Rays
Occlusion Max Distance
mental Ray Common Output Settings:
Normal Direction
Map size
Samples
Alpha mode
FG quality
FG reflect
UV range
Fill texture Seams
My point is, that no amount of me fucking with these settings produces a map anywhere remotely approaching the quality of XSI using the same models.
So in a nutshell, if anyone has played extensively with these settings, and gotten a magic formula that produces a result anywhere near as clean and tasty as XSI's, I'd gladly attempt to reproduce with them.
Other than that, you could try using the dirt map plugin for maya. We've found that it can give better results than regular ol' maya occlussion passes some times. http://animus.brinkster.net/index.html
You never know , maybe You will find Your happiness
http://www.maxon.net/pages/products/products_e.html
Up tools bar -
go to Render Settings/Ambient Occ./Apply to Scene
and then You can change some value if You need
(for ex. dirt map -128 default setting, You can go down to make more dirt Simples)etc. etc.In a materials You can add Environment about 20% to get more bright (white) rendering
It depends for what You're looking for.
It's rendering with SKY.
Up tools bar -
Objects/Scene/Sky
(not Floor)
http://www.alexmunn.com/html/class_levels_shaders.htm
http://www.game-artist.net/forums/spotli...chemist101.html
Meh, in that game-artisan tutorial they also get the blown out AO map
But yeah, I normally have problems with blown out AO results no matter what I use.
Whargoul, you hit the nail on the head thanks man. Using batch bake mental ray from within Maya, falloff is the key parameter here. Upping the value to 50 or so gives me beautiful AO maps, with a quality equal to the XSI ones.
However, as fogmann touched on, that's a little bit of a longwinded solution, and it requires UV's on the high poly, and it also requires a much bigger map than you need for the first bake, to allow for degradation from transferring the AO map into a different UV layout when you use transfer maps. So not ideal. So, in a nutshell, can anyone explain why I can't access the falloff parameter from within transfer maps? That one simple thing would make my life very easy. I'll probably contact Autodesk about it, and I'll speak with our mel guru TD tomorrow. But it seems really bizarre to me. The one parameter you need to get nice quality AO maps using transfer maps isn't available from within the transfer maps menu, therefore making the creation of AO maps from within transfer maps pretty much completely redundant. How very odd, sigh.
Here's another tutorial for maya 8 and higher, i usually up the samples to 256 like he does and haven't seen any issues.
http://www.game-artist.net/forums/spotli...chemist101.html
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Hah that's pretty interesting. fogmann noticed what the author of the tutorial apparently didn't. The first half of his tutorial on setting up AO shows nice results, the latter half of his tutorial which explains making AO maps *from within transfer maps* produces useless blown out crap, doh.
I have never got results like in that first xsi bake you posted Daz
So, in a nutshell, can anyone explain why I can't access the falloff parameter from within transfer maps? That one simple thing would make my life very easy.
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I'm pretty sure its in there. I was looking through transfer maps yesterday to see if I could provide any help, but I do remember seeing falloff there. It is most likely under one of the closed toggle menus, and I think it might even be under the toggle menu with Final Gather in it. I don't have access to Maya at the moment to give you an exact name.
I was thinking there might be a way to do this properly using the 'custom' shader option, so I'll tinker around with that.
Dunno if theyve made the transfer maps options better in maya 2008, but this works for 8.5 and probably some other versions:
- like Daz suggested, you need to create a custom shader. make the shader a mib_illum_lambert
- make sure the ambience value is white, now create a mib_amb_occlusion node, and plug it into the previous material's ambient value
-now you should have all the ambient occlusion controls you're used to available in transfer maps
(i don't think this is neccecarry, but I remember reading somewhere to check 'maya derivitives' for rendering transfer maps with mental ray. its buried in the performance dropdown of the translation dropdown in the mental ray render tab)
Following your steps however, i actually can't get this to work. It *might* be 'cos Im on 8.0, but I'm clinging on to the hope that it isn't. After fumbling around with some settings, I get *something*, but it's nothing resembling AO. Strangely it looks more like a one light directional light source.
Here's what I have, plugged into transfer maps as a custom shader:
Does that look right?
One thing I noticed is the output mode. Know anything about that? Also, i assume that in the transfer maps options, you need to perhaps untick 'use mental ray common settings' so that it uses the settings from this shader instead?
Any help appreciated.
Most of the AO bakes I've done in Maya are generally really grainy and over bright. Thanks for all the extra tutes/scripts/etc, guys and girl.
-caseyjones
from the top..
I've made a jpeg of what I think are the relevant settings, I had a bit of bother getting it working too so I probably missed something in my initial post. One thing I did notice was that if you leave it on 'all other meshes' for the source, it includes the low poly which makes a mess. I also changed the diffuse to black
the colours are weird so that if it comes out black or white, I know theres a problem, but if it's yellow or pink then it's probably my AO settings
(sorry for the layout)
http://redprodukt.com/wp-content/uploads/2007/12/maya_ao.jpg
I also uploaded the ma, I belive theres a trick to get it working in older versions that involves editing the ma and changing the version number in the file
http://redprodukt.com/post/maya_ao.ma
If you're curious, no matter what I tweak, I get this: http://www.daz-art.com/ao_prob.jpg
So on the left you can see the hi geo in silver, and the lo in red. Note in the AO map result at right you can see where the two meshes intersect, and that its only rendered the hi poly stuff that goes out beyond the low poly, not the stuff within. It seems like some kind of enveloping or distance issue, but umpteen gazillion combinations of tweaking that stuff provide nothing new. Bummer. Of course we have the whole 'cant upgrade cos were mid project' usual annoyance.
what about, using a custom attribute to discount the low poly mesh from the ao calculation?
I don't have maya on me at the moment and I don't remember the particulars, but there is a setting in the ao node that means you can say 'dont use objects with this tag' and if you then add a custom attibute to the object and give it the same value, the ao will ignore it. This seems like your best hope since the ao isn't using the transfer maps habit of ignoring the low poly.
All I can do at the moment unfortunately is mention that you can do that; without my test scene I can't give you the details, curse my leaky memory
I'll get those details when I'm back home, unless you've already given this a go
one thing I do remember- in the ao node you put a negative value as this variable, to say that you want to discount an object (for example -1) and a positive to say you want nothing but this object (1). maya's help tells you to put the same value into the custom attribute you create for the object, but what it really means is that in both cases, you put 1.
turn off all the options in the following tabs:
the render stats of the low poly, the mental ray tab (both in the shape node), and also, the mental ray 'flags' tab in the other node tab (expand mental ray, then expand Flags) once all that is off (realistically its probably only a few of those that make the difference), no more intersecting!
no intersecting low poly! woot
So far I've tried transfer maps and xnormal. Both give me blown out grainy maps. I was hoping TransferMaps would work after I raised my memory so I could play more. Apparently I was wrong?
I hope someone finds a solution!
I've been using the green channel from my normal map but that gives seams sometimes.
Yeah that's a definite limitation TWilson. I can get get some pretty insanely dense geo into maya, but of course, start trying to actually manipulate it or god forbid select all edges and soften them and a quit to desktop usually ensues.
Actually though, I know this is a maya thread but I've been getting great results from persevering with xNormal of late and been using that. I was put off it initially because my default result was always super blown out, but then I discovered that a combination of the spread angle cranked up as high as possible and tweaking mesh scale gives me really nice results.
Basically from what Daz has posted, it looks to me like the baked texture is taking information from the target meshes (the lowpolys) as well as the highpoly source - this is why it's only looking "right" on the sections where the highpoly pokes through the lowpoly.
Now I seem to be having the same problem, but with normals - I have my scene set up, 2 lowpoly target meshes inheriting normals from about 10-20 highpoly meshes (it's a mechanical object), yet whenever I use Transfer Maps to try and grab normals, it appears to grab the lowpoly normals too! Not only this, but it grabs them as though all the edges are hard (they aren't).
I can tell it's reading the source meshes properly, because the normals are coming out fine whenever the highpoly mesh pokes through the lowpoly, but beyond that I don't know what's up. I rendered out normals for a simpler object yesterday with exactly the same settings and it came out fine (with intersecting meshes and everything), now today it just won't seem to ignore the lowpoly when baking normals
It's like it's baking the lowpoly to itself, but with no soft edges... looks like crap and is very annoying. I asked our resident Maya guy about it and he couldn't figure it out either. All my settings appear correct.
I'm gonna try merging everything into a new scene, importing as OBJ etc. and see what fixes it. But it seems that it's a Transfer Maps issue, not just an AO issue.
Mopster dunno if I can help but I'll take a look at the scene if you like?
Bit silly that it doesn't do that, now I'll have to add a proper Smoothing thing to all the objects... why can't it just assume that I want to render them smooth if I'm viewing them smooth?
As with many things in Maya, I'm finding it's several steps to the same end result as one single step would get you in Max.
Also I find it incredibly annoying that Maya doesn't store Transfer Maps settings per scene/object, you have to save/load them every time you want to bake a different scene or set of objects, which seems like a horrible workflow, unless there's something I've missed?
Yay for productivity.
You can smooth the edges, but if you forget to merge the uvs you can still get artifacts when baking maps. If you're bakign AO and doing so by baking it into a texture for the high poly and then transfering that across as diffuse, remember to merge the uvs of the high poly too.
Doesn't take long, just select the object and in polygons menu set, go to edit uvs>merge uvs (don't to go into uv editor and select all uvs then file>merge, that takes longer and can cause maya to crash with a high poly mesh).
strange though, because 3dsmax produces blown out shite also.
I have never got results like in that first xsi bake you posted Daz
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You can adjust the settings in max to reduce the blown-out look. If you increase the 'spread' that works.
Or you can not use mentalray and use the light tracer instead. That also fixes the blown-out look.
It sounds like the method being used in maya just doesn't provide any options to fix it.
And happens all the time for me Rooster. I have the viewport info thing up all the time (displaying polys, uvs etc.) and watch to see the uv number shrink when I do the merge. Always goes down (quite a lot) when I import a model and merge.
On a slightly different note, one of the guys at work had one of the strangest problems I've ever seen. He had a head UV mapped, and it was looking relaly weird with the texture, even though the texture was fine and the uv map was fine. Turned out maya had taken each UV face in the map and rotated each one individually by 90 degrees, keeping the UV map looking exactly the same.
I didn't even know that could be done.