VRay Dirt

[alexthg]

just playing around with the new vraydirt material, looks very cool

but supposed I want to use vraydirt (ambient occlusion) for ALL my scene, is there any better way than to manually assign vraydirt mat to every diffuse maps on my material editor?

could override mtl + some postpro do the job?

[instinct]

simply put a pure white mat with the dirtmap in diffuse in override slot an comp it with multiply mode

[visualride]

simply put a pure white mat with the dirtmap in diffuse in override slot....

Could you elaborate on what kind of material you use first to apply a dirt map into the diffuse slot to get a solid white background?

Thanks alot for the tip!

[visualride]

OK, to answer my own question, and after waiting for a test render to finish, I realized that simply puting the dirt map in the diffuse slot of a vraymtl, and nothing else appears to work fine. Thanks again instinct.

[alexthg]

ah yes... that works! great thanks!

[alexthg]

don't forget to render to render-element vraydiffusefilter

[posterus]

Here my 1st attempt at it. Its nice but I was hoping it would be much faster that this. The scene has 4 omnis with shadows off. GI is off as well as environment light.
The mat has a radius of 5', distribution 10 and subdivs 8. Iplan to do some test animations next week to see how consistant it is...should be good since there is no GI.


-joe

[instinct]

just as a sidenote, you dont need ay lights at all when post-comping an ao pass. The override material can be a simple standard mat, white diffuse colour, 100% self-illumination. In the diffuse slot you put the vraydirt. Then when rendering you can turn off almost everything in the globals (lights, shadows, GI, reflections etc). That should give the lowest possible rendertime for an AO pass.

Thorsten

[Sawyer]

So ao cannot be a seperate pass. You nees an overide material and to use the diffuse filter render element. But then you can turn off lights for the rendering? Is that the correct AO workflow?

[instinct]

well it´s not an integrated pass as in renderelements. Vlado would have to code that...*cough*cough*HINT*cough*cough*

;p

[alexthg]

i tried with vraydirt with VRayLightMtl, and it worked too! but i need to crank up the multiplier high enough to get the white diffuse image.
so, i guess no need to render element-diffusefilter

[RErender]

I'm doing an animation where I am using my standard workflow and just adding a AO pass in post. Adds some nice detail. I just used a vraymat with a dirtmap in the diffuse slot and then added a max skylight with no shadows, seems to work well and render pretty quickly about 7 mins a frame compared to 25 mins for the GI frames + calc.

[dapeter]

What are you guys using as AO samples, and what image sampler works fastest?