Ambient occlusion in diffuse/color map or a separate texture?
I've never really though about this. Why have a separate texture for ambient occlusion? I've seen a few models that have baked the ambient occlusion into the diffuse/color map. What are the pros and cons for combining the AO and diffuse map?
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Generally, you should never bake your AO on your diffuse directly with your renderer, you simple don't have the control you need to make it look good.
everyone else? i highly doubt that - we are still far from super advanced shaders for most productions, besides some really high specs games - but even in titles such as crysis 3 the ao was part of the diffuse and not a seperate map. Not sure about the ingame cinematic models - but the normal in game models just have blended in AO maps. The only project i worked on so far with a seperate AO maps was Halo4, but the textures there have been really different from all productions i ever worked on.
yeah sure because what we've been doing since - forever - is creating physically accurate assets because the renderers we use are all physically accurate
definitely but not for all games and not for a while, i doubt with the next generation everything will be physically based, artistically its just very limiting. But when it comes to recreating any sort of realism, yeah sure no doubt materials will be more physically based. Still to run these in relatime, stuff will need to be faked A LOT still.
Cool, let's all go back to painting our lighting into diffuse textures...
Physically based isn't as limiting as you make out. Pixar made Wreck-it-Ralph using a physically based rendering system and that is definitely not a 'realistic' visual result: http://www.ictv.org.uk/wp-content/uploads/2013/02/Wreck-it-Ralph.jpg
From what I hear a large amount of 'next-gen' games are using physically based renderers, mor ethan you may think perhaps...?
pixar has all the time in the world to render a frame, i do not doubt that a lot of the next generation engines are physically based, but it doesn't mean that nothing is still going to be faked.
As for the lighting in diffuse, if it looks better ingame in 90% of the cases do it. Its all a matter of the game, the usual camera etc. i am totally not agains pjysically based rendering, but don't be so sure that everyone is going to use it.
YES, that's what I do! oh wait, you're being sarcastic....
Of course you're right, a lot of stuff still will be faked because "this ain't CG" which I hear all too often these days
Of course it isn't going to be used by everyone, but it's really good! :P I think it will be adopted more as time goes on, even by "non-realism" art style games. It offers advantages over current approaches even for these.
Really I was trying to answer the OPs question though - why would you separate your AO from your albedo texture? Because that's how real life works!
Real life is about getting the result, Baking AO has been a pretty standard texturing process not to say it will remain this way, but I would always keep it separate then you can experiment and work out what suits your project best and bake it in photoshop.