Home Technical Talk

Best AO Baking Methods

Hey guys i am having trouble getting a nice clean AO map i tried Racer445 method on the video of the AK, i have tried some of the methods that Laurens Corijen but they still give me really bad looking AO some places where its meant to be light they are dark (i always explode my model before baking anything) but when i apply it to the model it looks ok besides those dark areas but then i add the Diffuse and it goes almost pitch black (basically im just re adding the AO as Diffuse) I am useing Marmoset 1.02. Here are some images of how my AO and Diffuse look like wen applied to the model and on their own.

I had to crank the light brightness up to 3 for it to not be so dark.

RK_MP121.png

I dont know if this happens because i am making a Complete map instead of a Lighting Map.

RK_MP121CompleteMap.png

And here is the Diffuse look at how light the Green areas are but they end up soo dark in the Engine with the AO on as well.

RK_MP121Diffuse.png

any ideas? on good methods for rendering AO? please let me know thanks

Replies

  • m4dcow
    Options
    Offline / Send Message
    m4dcow interpolator
    I'm pretty sure you don't want to explode your model when you are baking AO because you won't get the actual occlusion of where parts come together (you do want to explode moving parts though). Some people will also do a low res version of the AO and combine it with the high res so the edges line up with the low poly version.

    What seems to be happening with you AO bake with one side being darker than the other is that the parts are close enough to eachother to contribute to the AO map, usually there is some way to reduce ray distance to fix this, but like I say You shouldn't be exploding for an AO bake.

    I don't know why your model is showing up so dark though, but I'm no marmoset expert, hopefully someone else will chime in.
  • GeeDave
    Options
    Offline / Send Message
    GeeDave polycounter lvl 11
    Your lightmap looks dark all round to begin with, so there's a problem right off the bat. If you want greater control though, you should absolutely be rendering it separately and doing the merge in something like photoshop (on a multiplied layer).

    Personally, for my AO bakes I will switch to MentalRay and use the Ambient Occlusion texture element, as opposed to LightingMap.

    AO_MR.png

    I've got a semi old tutorial covering various AO methods (rendering, baking and projecting)... it might be of some use to you:

    http://garydave.com/2010/09/ambient_occlusion/
  • Noors
    Options
    Offline / Send Message
    Noors greentooth
    You don't tell which method you used ?
    A complete map will also bake the grey of your diffuse material by default. Haven't read the all tutorial, but he maybe pushes the self_illumination to 100% to avoid that. The ambient occlusion render element is ok, but i rather like to set it in the material, to make quick control preview.
  • HornyRhino
    Options
    Offline / Send Message
    @ m4dcow: Ahh, i figured as much but was not quite sure that that would actually have an affect to the AO. Tahnks for pointing it out. I will put the model back into place and then re-bake... i was dumb enough to not set a Time Line so i cant go back to how it was before Exploding :P bad habits i guess.

    @ GeeDave: Separately in which way? could you please explain? i got the method of baking the AO with CompleteMap from Racer445 maybe i did not let the video go further to see if i was doing it right or not. Thanks for the Tutorials i will def be looking into it.

    @ Noors: well in the Laurens Corijen Tutorial i pretty much did the First one and the last which he says that that is his preferred method of Baking his AO, i tried it and my AO came out HORRIBLE i must have def did something wrong. Could you please explain how u set it in the Material? these are all new things that will be great for me to know and for who ever need any info on Baking AO in the future.

    Thanks guys.
  • Quack!
    Options
    Offline / Send Message
    Quack! polycounter lvl 17
    Render AO exploded, then render AO unexploded all with Mental Ray as Dave explained. Then combine. Cleanup in photoshop.

    For that dark highlighted area, was it close to another part of the model even when exploded?
    As for the lighting methods, where is the light in your 3d shot? It doesn't look like there is one and that could explain darkness.
  • HornyRhino
    Options
    Offline / Send Message
    ahh ok... easier for me to understand :P

    well they are not that close maybe i will move them more apart. There is a Skylight in the scene it is not centered to the world though i just put it where ever in the scene.

    The skylight is in perfect 0,0 but i did elevate it higher than the model however that is not how i baked it the first time the light was in a totally random place. here is a screenshot of the exploded model.

    explode.png
  • Ark
    Options
    Offline / Send Message
    Ark polycounter lvl 11
    A skylight's position/rotation/scale doesn't matter within a scene. Have your set your environment colour to be completely pure white?
  • HornyRhino
    Options
    Offline / Send Message
    lol sorry guys im noob with baking this is the first model i am baking and going to texture so please a little patience and try to explain things... i need a faster processor chip in my brain :P so is it:
    enviro.png

    P.S my girlfriend is blond so i might get blond moments with this stuff :P
  • 3DRyan
    Options
    Offline / Send Message
    3DRyan polycounter lvl 8
    Have you tried baking with Xnormal? It works quite well.

    http://eat3d.com/free/xnormal_overview
  • Ark
    Options
    Offline / Send Message
    Ark polycounter lvl 11
    Under Environment and Effects, under Common Parameters, change the Background Colour to White and untick Use Map.
  • EarthQuake
    Options
    Offline / Send Message
    chaosquack wrote: »
    For that dark highlighted area, was it close to another part of the model even when exploded?

    This is certainly the issue for that area.
  • HornyRhino
    Options
    Offline / Send Message
    ah... Thanks EarthQuake... am trying a dif approach this is my plan. explode the whole model and then bake a Normal Map for better normal map quality and then bake an AO map but with the model not Exploded so that i dont get those dark areas... does that sound good? and i noticed that with a Lighting map Bake the scene in Marmoset is a HOLE lot lighter than with the Complete Map.
  • Joshua Stubbles
    Options
    Offline / Send Message
    Joshua Stubbles polycounter lvl 19
  • HornyRhino
    Options
    Offline / Send Message
    hmm... looks real easy and quality looks great will give it a try. Thanks Joshua for the link :D
  • boyluya
    Options
    Offline / Send Message
    boyluya polycounter lvl 10
    Hey guys, I'm also trying this method but I can't find the "discard backface hits" option (just like in xnormal) so that floating geos won't cast shadows. Maybe you can help me out thanks.
  • m4dcow
    Options
    Offline / Send Message
    m4dcow interpolator
    boyluya wrote: »
    Hey guys, I'm also trying this method but I can't find the "discard backface hits" option (just like in xnormal) so that floating geos won't cast shadows. Maybe you can help me out thanks.

    Check the AO wiki link that joshua posted above, there are a couple different methods of doing this and their gotchas listed.
  • boyluya
    Options
    Offline / Send Message
    boyluya polycounter lvl 10
    m4dcow wrote: »
    Check the AO wiki link that joshua posted above, there are a couple different methods of doing this and their gotchas listed.

    Didn't see that. Cool thanks! :)
  • HornyRhino
    Options
    Offline / Send Message
    Super Happy Cow: huh?? i can have less islands?? hmm what is this blasphemy :P also can i give the whole model 1 smooth groups or is it best to give 90 Degree angles a dif smooth group? i normally give 90 degree edges a dif smoothing is that ok? i normally detach hard edges in my UVs i guess that's why i have so many islands? to reduce that is it ok if i just give them diff smoothing but still leave them attached?
  • r_fletch_r
    Options
    Offline / Send Message
    r_fletch_r polycounter lvl 9
    HornyRhino wrote: »
    Super Happy Cow: huh?? i can have less islands?? hmm what is this blasphemy :P also can i give the whole model 1 smooth groups or is it best to give 90 Degree angles a dif smooth group? i normally give 90 degree edges a dif smoothing is that ok? i normally detach hard edges in my UVs i guess that's why i have so many islands? to reduce that is it ok if i just give them diff smoothing but still leave them attached?

    Its fine. you need to make theses splits to get a decent normal map render.
  • HornyRhino
    Options
    Offline / Send Message
    @ r_fletch_r: ahh i see thanks. because a tutorial i read said that i had to give my model 1 smoothing group so i was confused. thanks for clearing it
  • r_fletch_r
    Options
    Offline / Send Message
    r_fletch_r polycounter lvl 9
    This is a really complex subject im afraid. both setups have their place and reasons for using them.

    long story short. if your rendering your normals in max and displaying in Marmoset you need to make the splits.

    Earthquake and Perna have explained the subject to death. I would do some searching and read their posts. There's allot of misinformation on the subject but if you stick to EQ and Pers information you cant really go wrong
    (they know stuff!)
  • HornyRhino
    Options
    Offline / Send Message
    yes i noticed, they know quite a lot. ah... i see but lets say i would like to use it in UDK for making a small demo how should my norms look like? less islands and less gaps? and about the Diffuse, i normally back at 4096 x 4096 should i re-size as soon as i import to Photoshop or paint all the detail and then Re-size?
  • Quack!
    Options
    Offline / Send Message
    Quack! polycounter lvl 17
    A starting point is that if it is on a uv island make it a seperate smoothing group. Model your object with this in mind. Keep seams hidden or tiny and use as few islands as possible.

    Textools by Renderhjs has a built in script to his tools that seperates all your smoothing groups by the uv islands you create. Bake after running the script.
Sign In or Register to comment.