Baking AO using MR
I'm trying to bake out an AO map using Mental Ray but the results I get are...less than adequate. All I end up with is quite a noisy mess.
Here's the result of a bake.
And here's the mesh.
I looked at a bunch of different methods including the ones on the wiki and I still get this awful result.
All I want is some nice and well-defined shadows.
Here's the result of a bake.
And here's the mesh.
I looked at a bunch of different methods including the ones on the wiki and I still get this awful result.
All I want is some nice and well-defined shadows.
Replies
You would need more variation in your source to get a different result, in any app.
And as EQ said this is what you should expect from that mesh, if we are misunderstanding what you mean, then provide some more info
Describe what you'r trying to achieve.. perhaps you've got the naming wrong.
From what I see, everything is as should be, walls are imperfect, especially brick made ones, which you're getting, which should be fine, which is what the source shows.
Also, the shadow question is extremely general. AO renders out local based shadows from each mesh, as a general overall render from the model. If you want more 'defined' insets, you could have beveled the models abit for the slight fall-off (straight baking for AO's and Normals is iffy at best).
Again, I'm winging it, I have no idea what you're looking for.
What I'm really wondering is how you can achieve such clean results as that found in one of PhilipK's tutorials. IE, like this:
You often have to exaggerate things to get them to bake well. You can count on small details being lost or barely making an impact.
I think he has some other tutorials about this too, one explains why you shouldn't go crazy and sub-divide like mad and waste your time painting sub-details.
Always keep in mind what you think will be your final output size will be and plan on that getting hacked down a level or two which happens quite a bit. If your details only hold up at higher resolutions then you're making it wrong.
Rendering out a complete map will get everything, diffuse, spec highlights and directional shadows. all stuff you don't want in your AO.
A complete map will bake the scenes lighting into the map, if you don't have any lighting in your scene it will go with the default viewport lighting which is based on the viewport camera position. If you move the camera around it will bake differently every time. Its a bit like a flashlight attached to your view.
Also if you're scene lighting doesn't match the game lighting you're going to have some kind of unpredictable directional lighting not matching your in game lighting.
If you're going to render AO outside of MR you do a diffuse map with lights and shadows turned on and a VERY specific light setup aimed at giving you the same results or something that closely matches your in game lighting.
Then you need to model your blocks like Philip has. On yours the detail is small and shallow. Adding larger chips and some deeper indentations will get you closer to Phillips bake.
Also in that bake you can see that Philips bricks do not form a perfect flat surface, some of them are recessed into the wall.
Some (physics/graphics guys) argue that a skylight in a scene with a white lambert material, and some floor geometry is a more "true" representation of AO, depending on what you determine to be 'real'.
Sunlight, vs artificial computation of a white particle bouncing around the surface area.
imho, i prefer to use whichever you think looks better.
Sunlight will look fine in a sunlit scene with no varying light, it doesn't hold up if it's a street light lit scene (for example) as well.