DFAO on large scaled objects

Hey all,

I have another DFAO question.
I understand theres a object size limit for DFAO to be generated on meshes. Is it alright to scale up those meshes to larger sizes and for it to not cause any problems?
I would guess the resolution of the AO would loose some detail, but for effects such as distance field shadows, are there any possible issues?

An example case would be building a larger mountain out of “smaller” but still quite large rocks, having a rock scaled up x10-x100 times it size and still have the mountain cast shadows wouldnt be an issue?
I noticed in the kite demo project this is the workflow.

Also, are there any performance issues with having larger scaled meshes with DFAO on?

Cheers,
Leighton

There are two issues with scaling up meshes to huge sizes: 1) low effective resolution / high memory consumption because volume textures don’t scale up well, and 2) increased GPU cost during cone tracing because culling happens on a per-object basis and those huge meshes have to be traced by all surroundings. These affect both DFAO and RTDF shadows. By default there’s a cutoff where meshes larger than the threshold will be excluded, you can change this to whatever you want.

float GAOMaxObjectBoundingRadius = 50000;
TEXT(“Objects larger than this will not contribute to AO calculations, to improve performance.”),

Hi,

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Hi Ben,

This is fine by me :slight_smile:

cheers!

Thanks for the answer Daniel! Its given me enough info to think about moving forward on how to tackle larger objects. The code will also be handy if we need to tweak the cutoff sizes :slight_smile:

cheers!