VRayDirt with Bump?

[brobins]

Apologies if this is painfully obvious but I am struggling to find a good way of rendering an AO pass (VRayDirt ExtraTex) that contains all the bump information from the scene shaders? I mean I realize why this wouldn't work as the ExtraTex is simply applying that material to everything in the scene at render time but is there a way using Vray to achieve what I want?

I remember being able to achieve this in Arnold by tagging some additional AOV shaders to the shading groups of the scene shaders, is there something similar possible in Vray?

My end goal is to have a AO pass/element/AOV that also has bump information.

Many Thanks

Ben

[SonyBoy]

I don't think this is possible.

[guillaumelepage]

Hi, this is not possible in Vray as far as I know because VRayDirt only works with actual geometry, and bump mapping has no influence on the geometry. It's only a shading effect.

Although a possible simplistic solution would be to plug your bump map in a VrayExtraTex render element and multiply that with your actual VrayDirt pass.

[seandunderdale]

I think this is doable but maybe not as an AOV.

As a basic test I was able to setup a bump shader with a standard vray material in the base slot with no diffuse. In that vray material, assign a vray dirt to the self illum slot and adjust the dirt map accordingly. Then plug your bump map into the bump slot of the bump shader. This gives a bump map over an AO effect.

[brobins]

This works great as an additional pass, thanks!

Would be great to be able to do this 'on mass', or even as an AOV.

Cheers

[SonyBoy]

Interesting hack!