Recipes for highquality AO bakes in Maya?

alexk

I spent the day trying to learn some AO baking. Although I've nearly messeed around with every slider and number in the AO Transfer Maps menu, I can't seem to get a high quality AO map.. that is, baking from a high poly model to a low poly. Here's some pics...

This is my low poly (using Maya's built in polycrunch) and high poly models


This is 2 cubes I made for a ceiling and floor, it seems to help the AO


This is my Transfer Maps settings. I've unchecked "Use Mental Ray Common Settings" because I've found it doesn't really do much(?)


This is my resulting AO map which is not too bad, but if you look closely, it has a "noise" to it. And if I turn up the "Occlusion Rays" setting, it becomes more apparent and spread. Which I find stupid, because in the Maya help, it says if you want a higher quality to turn that setting up... LIES!


This is the quality I want, pic courtesy of eat3d.com, this was done in 3d max and the author said it took a few hours to render this out


So, I'm looking for tips on baking AO maps similar to the quality of the one eat3d.com did.. granted, my high poly doesn't have as much lumps and stuff, it doesn't even come close to the details on eat3d's... blargh!

pior

Hmmm that Eat3d AO exemple doesn't really look like AO to me...

Ever tried Xnormal? It renders AO maps in seconds literally.

JordanW

I concur with pior, xnormal is fast as all get up and it's pretty easy to use once you learn its UI. I also recommend using Crazybump to generate some AO, it's probably not physically accurate but it doesn't really need to be, it just needs to look good

Ghostscape

That Eat3d map looks rather attractive and detailed. It also looks like it has directional lighting baked into it, and doesn't appear to be an ambocc bake at all.

CheeseOnToast

Like the others say, ditch Maya for AO and learn to use Xnormal. The results are better, faster and can be done with multi million poly models with a high number of rays. Maya chokes on around 1.3 million polys for me, and I have to use very low values for raycasting. It takes a bit of experimentation to get a nice result out of Xnormal at first, but once you've got your settings sorted its easy after that. I'll post mine tomorrow when I'm at work.

A quick and dirty lightbake in Maya can be done with a couple of ambient lights though. Turn "ambient shade" down to about 0.25 for both, and move them around till you get something that looks decent (in high quality rendering mode).

alexk

I'm pretty sure its an AO bake, but I will check the tutorial again. I'm pretty sure, because in the pimping section, another user is using the same eat3d tutorial method with similar results. here's his AO attempt



the post is http://boards.polycount.net/showthread.php?t=53632&page=2 (page 2 of the thread)

I'lll definetly give xnormal a try in the next few days

bugo

yes, i just use or Turtle plugin or Xnormal
Turtle has some great futures in AO and Normal map. But if the mesh is too high (more than 3million) i use xnormal.

Tumerboy

Well, they may be using them in a similar fashion to AO but those Eat3d ones definitely are more like straight up lighting, baked down to texture level. It's diffused lighting, but it's still directional (which true AO isn't)

JasonLavoie

Hey alex, I actually used 3D max to render out my maps, I find that I get better results, which is weird.

I actually haven't had a good AO map rendered out of maya yet man, I was just checking the settings and everything is basically the same except for one thing. In 3d max you can set the number of samples per pixel.. really don't know what that means but that's the only difference.

Try using mental ray settings instead... if not then got to xNormal I guess and try that, unless you have 3d max.

Good luck buddy

alexk

JasonLavoie wrote: »

Hey alex, I actually used 3D max to render out my maps, I find that I get better results, which is weird.

I think I need to just get it over with and switch over to Max, lol.. ughh. I know the "samples per pixel" setting in Maya, I'll mess around with that more later.. and also check out Xnormal some more.. <big sigh> thanks

kary

xNormal AO tutorial: http://donaldphan.com/tutorials/xnormal/xnormal_occ.html

East

Ghostscape wrote: »

That Eat3d map looks rather attractive and detailed. It also looks like it has directional lighting baked into it, and doesn't appear to be an ambocc bake at all.

Having followed every step in that tutorial I can vouch for it being AO. He does use a ceiling and a floor (if I remember that correctly) to "capture" the rays that are being cast so they don't bounce off into infinity.

I also recommend giving xNormal a try, although I haven't taken the time to fiddle with all the knobs so the quality I get from xN is normally (har) far inferior to what I get in Max.

pior

Well I dont want to beat a dead horse here but these renders definately show a white-up/dark-down look. That might be cause by that floor and ceiling setup - but all in one it does not look like a proper occlusion map to me.

All in one the creases don't get dark in that example, and that would sure look odd in an engine blending shadows and ao in a accurate manner.

But then again, if this is to be used as a mere detail layer on a texture it will look alright I guess - even if a bit directional.

I'll try to put a Xnormal example together. On a 64 machine it only takes *seconds* to generate a 1024 AO map!

Riki

Tumerboy wrote: »

Well, they may be using them in a similar fashion to AO but those Eat3d ones definitely are more like straight up lighting, baked down to texture level. It's diffused lighting, but it's still directional (which true AO isn't)

The pillar used a real Mental Ray AO but sometimes with certain env pieces you do simulate how it will always be in game to give it that extra level of realism. This doesnt work well for dynamic objects and characters, but for a Pillar that will always be upright indoors its nice to have those contact shadows.
No directional lights were used, instead you just make a floor and whatever else will always represent it being in your game, same thing goes for the pipe on the side, this works as long as that pipe never comes off, if it does come off then you would need to bake them out separate.

In the new texturing DVD I go through creating an AO with the standard max lighttracer that has been around since max 5, its much simpler to use and IMO creates almost as good AO maps if not just as good. Ive never really been able to tell the difference in the end result.