AO maps on large assets?

jordank95

Working on some large cliffs/rocks and using tiling textures and masks to texture them. Do people generally use an AO map for the overall rock or large assets in general? If so, not sure how'd I'd add this into my material setup? Or is AO generally not used for large rocks?

Yerus

Your intentions are for video productions or games?
U can use AO as a complementary thing, by post-producting it with an adequate G-buffer pass/render pass.

jordank95

This is for games. In Unreal Engine mainly, but applies to other engines as well. 

sprunghunt

yes I would normally use an AO map in Unreal. For a large object like a rock you could try multiplying a 'big' AO map over the top of a smaller tiling map. 

For a big rock (like a cliff) I would actually do something similar to all the maps - have a 'big' normalmap that is mixed with a smaller tiling normalmap etc

jordank95

sprunghunt said:

yes I would normally use an AO map in Unreal. For a large object like a rock you could try multiplying a 'big' AO map over the top of a smaller tiling map. 

For a big rock (like a cliff) I would actually do something similar to all the maps - have a 'big' normalmap that is mixed with a smaller tiling normalmap etc

Thanks! I figured that was what it was. Ill set up something in my material. 

sprunghunt

jordank95 said:

sprunghunt said:

yes I would normally use an AO map in Unreal. For a large object like a rock you could try multiplying a 'big' AO map over the top of a smaller tiling map. 

For a big rock (like a cliff) I would actually do something similar to all the maps - have a 'big' normalmap that is mixed with a smaller tiling normalmap etc

Thanks! I figured that was what it was. Ill set up something in my material. 

Have a look at epic's Agora asset set from Paragon - it's free - and there are a bunch of assets that use a similar blended material setup

https://www.unrealengine.com/marketplace/en-US/product/paragon-agora-and-monolith-environment

ZacD

The UE4 devs seem to suggest using the AO texture slot for cavity scale AO only, and that medium to large scale AO should be handled by screen space AO, baked lighting, or distance field AO. Otherwise your doubling up AO. 

Eric Chadwick

Depends. What's your target hardware?

Most people always assume PC/console is the target. But if you're doing mobile, or VR/AR, baked AO is nearly always going to win over realtime/screenspace AO. The hardware just can't handle it.