Force Materials console error

[psanitra]

I`m just rendering gray/clay renders of some older scenes, that have mantra/principles shaders on it. So i`m using Force materials to override the material globally to my vray material. It`s working fine,rendering wise, but console still list the error that it cannot export principle shader.

VFH [Info] * Build 29c900e from 28 Aug 2019 04:34
VFH [Info] * V-Ray 4.12.03
VFH [Info] V-Ray: Loading plugins from "c:\Program Files\Chaos Group\VrayHoudiniNightly\appsdk\bin/plugins/vray_*.dll"
VFH [Info] * Processing scene for frame 1000.000...
VFH [Error] * "/mat/Gray_Mantra": Can't export "principledshader::2.0" node! This must be handled by getConnectedNode()! Please, report this.

I guess this error should not appear right?. If there is a force material on the V-Ray ROP, there is no reason to trough original materials and export them.

thank you

[bdancer]

"Force materials" is not for overrides, it's for upcoming support of Alembic delayed "shop_materialpath" material assignment (so it means "force" export specified material nodes so that they'll become available in the vrscene for render-time shop_materialpath handling).

For global override you should use:
1. Renderer -> Options -> Materials -> "Material Override"
2. Stylesheet

[psanitra]

yeah, i tried that too, using material override it`s giving same error, and force materials is empty....

[bdancer]

psanitra, tnx, I'll fix this.

[ronald_a]

"Force materials" is not for overrides, it's for upcoming support of Alembic delayed "shop_materialpath" material assignment (so it means "force" export specified material nodes so that they'll become available in the vrscene for render-time shop_materialpath handling).

For global override you should use:
1. Renderer -> Options -> Materials -> "Material Override"
2. Stylesheet

Do I understand correctly that this will make it possible to make material assignment before saving the alembic and have them render right from the packed alembic?

[bdancer]

> Do I understand correctly that this will make it possible to make material assignment before saving the alembic and have them render right from the packed alembic?

Yes, exactly as you've requested here https://forums.chaosgroup.com/forum/...packed-alembic
You could even try it now if you have access here https://nightlies.chaosgroup.com/#/v...ghtly/20190903 (builds with the newer V-Ray Core; starting with vray_adv_42090)

[ronald_a]

> Do I understand correctly that this will make it possible to make material assignment before saving the alembic and have them render right from the packed alembic?

Yes, exactly as you've requested here https://forums.chaosgroup.com/forum/...packed-alembic
You could even try it now if you have access here https://nightlies.chaosgroup.com/#/v...ghtly/20190903 (builds with the newer V-Ray Core; starting with vray_adv_42090)

HAHA!!! Very nice, thanks a lot! Currently "a bit" busy, but I will look into it as soon as I can.I also like the fact, that there is a new vray core. I hope this fixes some/all of the threading issues I had with volumes and packed alembics as well.

[ronald_a]

I was just looking for the "force material"/packed ABC Material feature. Where is this again, can't seem to find it?

[bdancer]

You need a build from that section https://nightlies.chaosgroup.com/#/vray4houdini/nightly. "Forced Materials" is located at ROP -> Objects.

[ronald_a]

bdancer hmm, I exported the alembic with materials assigned through the material node and put the materials used into the forced materials on the ROP but somehow this is not working. what am I doing wrong (scene attached)?

also, if this is the workflow, I'm not sure how I like the fact that I have to put the material in the ROP. Is there no other way to do that. In Arnold (and they also just added that) it "just works". So if you have the "shop_materialpath" attribute exported into your abc, it will pick it up (which is actually even better than how mantra handles it). after all, its just a good old attribute like any other in an alembic which vray can extract without problems (I'm sure from a dev point of view you may not agree with me .

[ronald_a]

sorry, the arnold part was not true, they actually also have a similar workflow

[Gosho.Genchev]

Looks like this hasn't made its way to the builds you guys have access to. We have 'nightly' nightlies and 'stable' nightlies, the stable ones get the tested changes and are the ones you get by default. For the 'nightly' nightlies you should request access from the support@chaosgroup.com

I'm not sure how I like the fact that I have to put the material in the ROP. Is there no other way to do that.

If you want everything declared, just put a wild-card in there. This will export every single material in your scene.

[bdancer]

> it will pick it up (which is actually even better than how mantra handles it).
> I'm sure from a dev point of view you may not agree with me

I could agree that it'll be much smoother from UX perspective, but on the other hand I'll have to open read and parse Alembic file before each export, not sure how cool it that if you have some lets say 4Gb abc.
I may research how fast this could actually be a bit later...

[ronald_a]

Looks like this hasn't made its way to the builds you guys have access to. We have 'nightly' nightlies and 'stable' nightlies, the stable ones get the tested changes and are the ones you get by default. For the 'nightly' nightlies you should request access from the support@chaosgroup.com



If you want everything declared, just put a wild-card in there. This will export every single material in your scene.

I think i have access to the nightly nightlies. Arent't these the ones with core 4.2.xx? I have the forced material entry on the ROP, it just doesn do anything. did you take a look at my scene?

[ronald_a]

> it will pick it up (which is actually even better than how mantra handles it).
> I'm sure from a dev point of view you may not agree with me

I could agree that it'll be much smoother from UX perspective, but on the other hand I'll have to open read and parse Alembic file before each export, not sure how cool it that if you have some lets say 4Gb abc.
I may research how fast this could actually be a bit later...

I believe this is what arnold does, they have a checkbox that says "export referenced materials". So I suppose they look into the abc files on export. But if the wildcard works, which i suppose exports all materials in the scene, that would also be fine for now.