8. Vray Operators

Overview

The ThreeKit platform offers a choice of four main operators that are specific to Vray usage:

• Template Override

• Vray Rounded Edges

• Vray Subdiv/Displacement

• Vray Material Wrapper

These operators are available to apply in multiple locations, each location acting as an override to its children. The Vray parent/child hierarchy on the ThreeKit platform is as follows:

1. Composite Asset - parent of Models

2. Mesh Nodes - parent of Materials

3. Materials - base level

This means that if the user adds a Vray Rounded Edges operator on a material, which in turn is also assigned to a mesh that also has the Vray Rounded Edges operator on it, then the only instance of that operator that will take effect is the one on the mesh. The Vray Rounded Edges operator on the material applied to that mesh will be ignored. In turn, if the mesh is added to an Override group inside a Composite Asset layer, and that Override Group also has the Vray Rounded Edges operator applied to it, then that will override the settings on the mesh.

Template Override

The Template Override operator is the only one in this list that can’t be applied to the Composite Asset override Groups. It also makes no sense to apply it to a material, even though it currently shows up in the list of Operators there.

This operator is designed to allow the user to override custom TK_ material attributes, at the mesh level.

For example, if a template Fabric material is to be assigned to multiple meshes, each mesh may require its own specific normal map. For this purpose, every mesh would need to have the Template Override operator assigned to it, with a Map-type attribute that has the same name as the TK_ property on the material that needs to be overridden.

Let’s say the material has a property called TK_NormalMap. Then, each mesh would have a Template Override operator that looks as follows:

The only difference from one mesh to another would be the Map Asset.

UDIM texture setups are another example of how this operator can be used. Although ThreeKit does not currently support UDIM texture setups in configuration, the Template Override can offer an alternative. It does require that the mesh is first separated into the different components that require individual textures. Once the individual mesh components are imported to the platform, the Template Override operator can be assigned to each mesh, with the TK_ attribute set to the individual texture that is supposed to match that mesh.

Vray Rounded Edges

This operator can be used very similarly to the way it would be used inside Maya or 3dsmax.

It is available through the Material Operators on either a Vray Material, a mesh node, or a Composite Asset Override Group inside a Layer.

For additional information about this feature, please read the Vray documentation for Maya and 3dsmax.

Vray SubDiv/Displacement

This operator can be used very similarly to the way it would be used inside Maya or 3dsmax.

It is available through the Material Operators on either a Vray Material, a mesh node, or a Composite Asset Override Group inside a Layer.

On ThreeKit, this operator combines a few separate features that Vray provides internally. It is a combination of Subdivision and Subdivision Control, as well as Displacement Map Control. Since these features are interdependent and not mutually exclusive, they can be accessed through this one single operator.

This means that if the user needs to only add Subdivision control to their mesh/material/override, then all they need to do is to add this operator as is, without assigning a displacement map. The lack of a displacement map asset will simply apply only the Subdivision effect.

One feature to note is that the user can only assign texture assets to the Displacement Map. ThreeKit does not currently support the assignment of Vray material assets, or any other kind of shader network from a vrscene.

The map used for Displacement will also be always assigned using the RAW/Linear color profile.

For additional information about this feature please read the Vray documentation for Maya and 3dsmax.

Vray Material Wrapper

Similar to the previous two operators, this one can also be used either on Mesh nodes, Vray Materials, or the Override Groups inside the Composite Asset layers. It is a combination of the Vray Material Wrapper along with Vray properties found on meshes.

There are many ways in which this can be used, but here are several typical uses for it:

• Primary Visibility - Prevent a mesh from being rendered in the color channel, but still appearing in the reflections, refractions, shadows, and GI of other objects.

• Matte masking - use a mesh to mask out parts of the render.

• Matte + Shadow capture - use a mesh to capture only the shadows of another object.

The most often place where this operator will be most useful is on the Override Groups inside a Composite Asset Layer. In that case, it is usually when shadows need to be captured, or a separation of components by layer. The Matte masking feature is key to enable this separation of components by layer.

For more information on this operator, please see the Vray Documentation.