Modo material question.

[Monkeybrother]

Hi. I'm playing with the beta and started loading old Modo scenes to try it out. It seems that a lot of modo materials can be rendered directly in V-Ray, without any changes. If a material works without conversion, is it "bad" to use it as is? Will the render be slower or is there a possibility of errors?

Good job, by the way!

[vladimir.nedev]

You can setup modo's advanced material in a non-physically correct way ( more light bouncing off the surface than arrives at it), which can impact the render time with GI enabled.

Also you can setup modo's material to have different colors for reflections and specular hilights. This means I have to export two separate BRDF layers which handle reflections and specular hilights separately.
This may impact the render time as well, but my guess is not by much.

On the other hand modo uses a simpler formula for the fresnel term which we also implemented in our conversion. That might be faster than the more accurate formula the V-Ray material uses. Again this shouldn't
impact render times by much.

We are planning on adding a command to convert a modo material to a V-Ray one, and also modo's texture effects to V-Ray material texture effects.
This conversion won't be as close to modo's result as directly rendering with the modo material though.

Greetings,
Vladimir Nedev

[Monkeybrother]

Thanks.

A couple of material questions:

Is there currently an easy way to transfer v-ray materials from Max (for example) to modo?

I can't find any info on importing proxies yet? But when that is possible, how would you apply materials to a proxy? As I understand it, proxies only contain material ID's?

[vladimir.nedev]

Unfortunately there is no automated way to convert materials from other versions of V-Ray to V-Ray for MODO.
In the future we will add importing materials from a vrscene. So you will be able to export a vrscene in Max/Maya, and then import
selected materials from it in MODO.

Also we may add support for vismat/vrmat materials.

I am currently working on creating vrmesh files from selected items in a modo scene. These vrmesh files
will store not only material, but also part/selection tags for material assignment later on.

Right now you can use the Add Item -> V-Ray Geometry -> V-Ray proxy option in the "item list" to create
a V-Ray proxy item. You can then choose any vrmesh/alembic file you have from somewhere. The viewport preview/rendering
might be slower with an alembic file though.

As for material assignment, the material IDs will show up as material tags, you can select them in a mask layer in the shader tree.
I really need to add a command that creates masks for all material tags in a V-Ray proxy though.

Greetings,
Vladimir Nedev

[Monkeybrother]

Looking forward to the vrscene/vismat/vrmat support, that would be really good.

Proxies: I can load a vrmesh that was created in Max, but I can only render the preview mesh. Am I doing something wrong? Also, could you explain more about applying materials to proxies? I can't find the material tags.

[vladimir.nedev]

Strange, V-Ray always renders with the final mesh, the preview mesh is shown in the view-port and will be used by the modo renderer. If you want to use the final mesh when rendering with modo(or for the 3d view-port), you can change the "Preview" option
in the V-Ray proxy to "Render geometry" ( it defaults to "Preview geometry"). This will of course slow down the view-port for really heavy meshes.

The material tags should be in the drop-down for the "polygon tag" option of any "group" item in the shader tree.
For vrmesh files created in 3ds Max they are named something like mtl1, mtl2, mtl3, etc. based on the material id in Max.
For vrmesh files created in Maya they are named after the material that was assigned at export time - lamber1, etc.

It can get messy though with many material tags in the scene, that's why I am planning on adding a command to create the masks automatically.
So you will select a V-Ray proxy, hit the create proxy masks button, and it will create a mask for the proxy item, with sub-masks for any
material tags found in it.

Greetings,
Vladimir Nedev

[Monkeybrother]

I can't get the material tags to work. I can apply a material to an entire proxy, but I don't get any polygon tags. I can choose either "All" or "None" in the Polygon Tag dropdown, but nothing else shows up.

[Monkeybrother]

Strange, it seems to work on some proxies but not others. All of them work in Max.

[vladimir.nedev]

Hm, yes I forgot about that - only the newer versions of the 3ds max vrmesh export will output the material information.
It has been added at the end of 2012.

Also when exporting them you need to have consecutive face material ids. Any missing ids will mess up the export, for example no polygons
with id 1, when there are polygons with id 2.

Greetings,
Vladimir Nedev

[vladimir.nedev]

deleted (replied in wrong thread)

[Guilherme]

Hello,

'We are planning on adding a command to convert a modo material to a V-Ray one, and also modo's texture effects to V-Ray material texture effects.'

Any news? Is it already there? Thanks.

[vladimir.nedev]

Hello,

'We are planning on adding a command to convert a modo material to a V-Ray one, and also modo's texture effects to V-Ray material texture effects.'

Any news? Is it already there? Thanks.

I sort of gave up on this, as the result of the conversion will not be as accurate as just rendering with the MODO materials in V-Ray.

Greetings,
Vladimir Nedev

[Guilherme]

Ok, but it could be usefull if we get the V-Ray conversion makes internally (i suppose) as a starting point - basic stuff - instead of creating a new v-ray material everytime if we have a library of modo materials already. Thanks.

[vladimir.nedev]

Ok, but it could be usefull if we get the V-Ray conversion makes internally (i suppose) as a starting point - basic stuff - instead of creating a new v-ray material everytime if we have a library of modo materials already. Thanks.

That's the problem, the internal conversion is too complicated to be presented in the UI for the user to make further edits to.
So, I have to create another conversion process, which will not work as good as the internal conversion.

If you have a library of MODO materials, you can just use them without converting to V-Ray materials.

Greetings,
Vladimir Nedev

[Guilherme]

ok, thanks.