Vray Proxy

[damaggio]

Hello Chaos, first time using proxies in Maya 2017 windows 7 and did a small patch of dead grass with one texture, however once I import the Vray proxy, the texture is not included in the render, can't understand why.
Also rendering times is not that different, I've seen other posts here where people have seen the same issue, I understand that uses less ram and improves viewport performance but very different than when I render with mental ray proxies with all the textures included and much faster render times.
Can I get some info on this please?
Thanks guys.

[damaggio]

After some google research I found out that you need a VrayMeshMaterial to go with the proxy, but still after importing the Vray proxy the texture still not there, I'm very confused on this one guys and will be dealing with lots of grass and trees next few days.
Pleeeeease.

[damaggio]

Okay, a good friend of mine tried to helped me out over night but i'm still stuck on this, I cannot duplicate the proxy around the scene and still it comes in and renders just grey, no textures.
I read the Proxy docs page but did not help me...I also try the option "Automatically create proxies"
I'm, uploading the scene here.

[Mihail.Djurev]

It seems to be working fine here. Both regular import and "Automatically create proxies". What build are you using?

[damaggio]

that is 3.45, still when I render the proxy the texture file is not rendering, are my connections correct?... I must be missing something.

[damaggio]

Step by Step....
create cube, assign Vray material, assign a texture
Create sphere, assign Vray Material, assign new texture

Delete history, Save Maya file.
Select both objects Vray >Create Proxy
Open new blank scene, Import proxy, now once loaded vray mesh material has lost connections to texture and renders proxy with default Vray grey material..???

[damaggio]

Here's a new screen grab...

[damaggio]

Hi Mihail, I could really use some help here before the weekend, I got some work to do with these proxies if I get it to work...please.

[yolov]

The proxy itself is an external geometry format. It doesn't store textures or materials, only geometry. You need to make sure that once you import the proxy back into the scene, all materials and textures are properly re-assigned. To avoid doing this manually, you can use the auto-create option while exporting.
The VRayMeshMaterial is what is assigned to the proxy by default once it's imported. It's best used if you have more than one material to the proxy (i.e. a sphere and a cube living in the same .vrmesh file and respectively each having its own material) - then the mesh material will carry two submaterials - one for each object.
I couldn't really get into what's the problem you're facing - the scene you provided renders fine once I correctly repath the texture.
You problem is the export itself? The import? The material assignment after import?

[damaggio]

Hi Alex, thanks for the information, however I still don't understand why all the shaders and textures are still on my scene, in mental ray proxy nothing is ever loaded thus making my scene much more manageable and light.
One more thing too, after creating a proxy and importing into a new scene the materials and textures don't come over, it would be really time consuming to reassign everything on a model that has 20 or so shaders and textures.
The auto create proxy "does" work, but after deleting the textures and shaders from the Hypershade the model just renders grey, I thought that the VRAY proxy would store all information on the model but apparently that is not like Mental ray.

[yolov]

The mental ray and vray proxy systems surely differ.

The vray proxy file itself (.vrmesh) only keeps geometry. The shaders and textures are kept in the maya scene.

If you open up a scene where you have an object, with a shader assigned, which in turn has a texture, then you select the object and export it to a vray proxy, a vrmesh file is created.
Once you bring it back in the scene - a proxy node will be created with a mesh material assigned. The mesh material will hold connections to the respective shaders that the proxy needs (in the case I'm describing that would be 1).
You need to manually plug there the already existing shader that was previously assigned to your object before it was exported to proxy.

The auto-create proxy option just saves you that step.

If however, you auto-create a proxy and then manually delete the connected shaders - you will get a grey render, that is expected since those shaders are kept in the maya scene and now they've been removed.

A common workflow would be to have a separate maya scene with only your grass, auto-create a proxy from that scene and then save it as a maya scene - that scene will hold a vray proxy + all the shaders and textures. Then you can, for example, reference that scene as a whole asset package.

One thing we introduced with V-Ray 3.30 for Maya is the VRayScene node. Think of it as a proxy that also stores shaders, textures and lights on top of geometry.
The workflow is somewhat simple - you would need to again have only your asset in a maya scene and then export it to a vrscene file. It is done from render settings > common tab > exporter > untick "render" and tick "export to vrscene file".
Then in another scene where you wan't to use that grass (for example), you just go to create > v-ray > vrayScene manager, browse to locate your vrscene file and that's it. Alternatively, there's a shelf button that calls the vrayScene manager.

You would want to tick off "Add lights" for the vrscene node in the attribute once it's imported (Maya always has a default directional light that would get written to the vrscene to say the least).
The only thing to be mindful of is texture paths - the vrscene (just like the maya scene) only remember where the texture files are located so in case you move the textures afterwards, you will need to manually edit the vrscene with a text editor to fix that. OR take advantage of a little trick inside V-Ray's sleeve - keep copies of all textures used by that vrscene in the same folder where the vrscene file itself lives - V-Ray will load them from the same directory as the vrscene file if it doesn't find them on their original locations.

Let me know if you need help with anything of the above, it got a bit long and potentially confusing.

[yolov]

+ vrscene can have vray proxies in them too, if you find that convenient for your workflow.

[damaggio]

Hi Yolov, thank you so much for the thorough explanation, that helped me a lot, I'm testing the workflow you suggested, much appreciated.
RD