vraymeshmtl

[bradon]

can someone explain what the purpose is of the vraymeshmtl. i notice in the newer builds we get these grey shaders scattered for each object we turn into a proxy. this used to not be the case if im correct with the first version of vray the vrpoxy would retain whatever maya shader was applied to it. and the shader overide was in the vrayMesh node. so if i needed i could do my overides etc. all right there in one nice neat node.

It looks like in the vraymeshmtl we have a link to the old shader so i can see by defualt it automatically hooks up to the old shader that I had before I made the proxy (renders fine etc). but its making my hypershade sort of cluttered to have all these grey dummy shaders in the window.

whats the point?

[snivlem]

Using the old system, there were some big disadvantages:

Delete unused shaders would delete ALL proxy shaders
There were greater chance of corrupted shading assignments with referenced proxies


New system is much, much better - it's easier to reassign shaders now too. But yes would be good for Autodesk to implement a "Hide Shaders" option.

Please let them know about it:
http://www.autodesk.com/maya-sug

[bradon]

huh. i never experienced that it would delete my proxy shader when i used the delete unused shader maybe im mistaken?

how do you find its easier? if i re-assign a shader to a proxy object and then use delete unused shaders the grey materials go away and the shader is just linked to the proxy directly. seems like it would be alltogether better to bypass the grey "temp" shaders and either keep the shader that the proxy has when it was created or just re-assign like any ole mesh. maybe there is some technical thing im not understanding.

seems like the best workflow for now is to make all the proxy before assigning shaders otherwise i end up doing it twice. once before i create the proxy then i have to reassign again after the proxy so i can delete the grey shaders.

im just not experienceing shader corruption or missing shaders on my end but maybe i havent hit every case scenario where that could happen.

[snivlem]

I'm sure I tried it the other day with an old v-ray build and Maya deleted all connected shaders to the proxy when I used "Delete Unused Shaders".

With shader corruption, I had about 10 versions of different cars, each with about 20 shaders assigned to a single mesh - Maya continually stuffed up when I used these proxies as references into scenes + render layers.

Doing the same thing with the newer method never ever breaks shader assignment anymore which is a great relief. These are my findings anyway - maybe someone from V-Ray can shed some light why it was changed?

[vladimir.nedev]

The old system, with the shaders connected to the VRayMesh node, created lots of problems, because the shaders were not assigned to the mesh the way Maya expects them to be. For example, the shading switch utility didn't correctly find the shapes it is assigned to. Just assigning the shaders to the proxy mesh is not possible as well, as it creates a lot of history nodes between the VRayMesh node and the Maya mesh node. These tend to slow down a lot of operations ( for example, using a shading switch). Deleting them was not really possible since that meant deleting history and the VRayMesh node is part of the mesh's history as well.

Bradon is right though, a special case can be made when the mesh has only one shader assigned, when it is converted to a proxy. No need for a VRayMeshMaterial in that case. Right now, this is just handled by the general code, so it gets a VRayMeshMaterial as well.

And yes, delete unused shaders will delete any shaders that are not assigned to anything, but are just connected to a VRayMesh. It won't happen if the VRayMesh has only one shader, as in that case the shader is actually assigned to the VRayMesh. The problem happened when you have more than one shader.

Greetings,
Vladimir Nedev

[bradon]

thanks for the insight. we NEVER EVER assign more than one shader to a mesh as maya has lots of problems when you do a face assignments especially with render layers breaking and loosing shaders. of course you can merge multiple meshes into one proxy im guessing maya "might" treat that as a face assignment then not sure. we try to stay away from those case scenarios as maya doesnt tend to work well when we do that.

[bradon]

do you think its possible to add a checkbox in the vray proxy creation so that we can bypass the vrayMesh grey shader? so that the vray mesh would link directly to the shader it was assigned to before it was made a proxy?

[snivlem]

Why? I think the mesh shader solves more problems than it creates???

[vlado]

do you think its possible to add a checkbox in the vray proxy creation so that we can bypass the vrayMesh grey shader? so that the vray mesh would link directly to the shader it was assigned to before it was made a proxy?

This would only be possible if you exported a single object with a single material in the proxy file. If you exported multiple objects with different materials, then you still need the vraymeshmtl material.

Best regards,
Vlado