Ambient occlusion maps?
by Martin Askestad · in General Discussion · 01/04/2012 (8:16 am) · 5 replies
I've seen on several sites examples on how to create ambient occlusion maps. Haven't really seen a good explanation on why you should create static occlusion maps. Since Torque has a Screen Space Ambient Occlusion Post Effect built in, I just assumed that pretty much all game engines had that built in.
Is there a benefit to use Torque built in real time AO feature over pre-built maps? Is it better to have pre-built maps? The only reason for a pre-built map that I can see is that if you are making a game for mobile devices that don't support shaders. If anybody could share some light on this, I would be most grateful.
Is there a benefit to use Torque built in real time AO feature over pre-built maps? Is it better to have pre-built maps? The only reason for a pre-built map that I can see is that if you are making a game for mobile devices that don't support shaders. If anybody could share some light on this, I would be most grateful.
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Always have ideas for new games. But not always the motivation or the skill.
#2
01/06/2012 (2:23 pm)
Thank you for a great answer. One more quick question. Do I have a need for AO-Maps if If create proper light maps? Because a AO-Map seems like a light map lite to be honest. 
#3
[edit]
Personally I bake AO for some of my models and then transparently layer it over the diffuse texture in Gimp before saving the final texture out. It's a kind of cheaty way to get AO into your diffuse maps without any extra overhead. Obviously not going to work with tiling textures.
01/06/2012 (2:30 pm)
Technically they are the same thing and will certainly both be fighting for uvmap slot 1 (uvmap slot 0 being diffuse).[edit]
Personally I bake AO for some of my models and then transparently layer it over the diffuse texture in Gimp before saving the final texture out. It's a kind of cheaty way to get AO into your diffuse maps without any extra overhead. Obviously not going to work with tiling textures.
#4
01/07/2012 (1:05 pm)
AO would be part of any regular light map unless you wanted to do fancy stuff like reducing the AO power in brighter environments. I used to do the same trick as Steve, just overlaying the AO bake from Blender onto the regular UV map.
#5
01/07/2012 (2:23 pm)
Well in that case maybe I should take the time to install pure light, since I did invest in it after all, and stop mucking about with ao-maps. 
Torque Owner Daniel Buckmaster
T3D Steering Committee
2. Quality. I've never seen a post-pro AO effect that I liked. Baked AO is much finer, except, of course, on objects that move and animate a lot.
3. Control. Maybe this fits under quality. But you have a bit more creative control over AO if you're baking it in your modelling application versus leaving it to someone's shader implementation. Of course, you can edit the post-pro shader all you like, and adjust settings for different levels, etc.
Most of these factors aren't really important enough to replace SSAO with baked AO in the general case. But if you have specific needs, a particular art style to shoot for, or like me you can't stand SSAO, then baked AO is a fair replacement.