Overview

The VRayMultiSubTex texture allows the user to control any parameter that can be mapped based on the Object ID or Face ID on which the final material is applied. In the image shown here Get ID from had its type set to Object ID, and each of the Num IDs were given a different color via a VRayColor texture

UI Path

||Material Editor window|| > Material/Map Browser > Maps > V-Ray > VRayMultiSubTex

Parameters

Get ID from – Specifies the meaning of the ID parameters.

Face material ID – The VRayMultiSubTex will consider the face IDs of the object when feeding the data (color or texture) to the material.
Object ID – The VRayMultiSubTex will consider the Object IDs of the object when feeding the data (color or texture) to the material.
Random by Node Handle – Each node in 3ds Max is assigned a unique number (a handle) when it is created. This option generates the color index based on that node ID. It is useful because the node handle survives through scene editing - f.e. if you add/remove other objects, or rename them, you will still get the same colors.
Random by RenderID – The VRayMultiSubTex will assign random colors based on RenderIDs.
Random by Name – Generates a color index based on the name of the node that the texture is applied to. This allows the color to remain consistent if the object is merged into another scene, or X-Ref'd etc.
Random by ParticleID – The VRayMultiSubTex will assign random colors based on ParticleID (works for VRayInstancer source objects and Thinking Particles).
Random by InstanceID – The VRayMultiSubTex will assign random colors based on InstanceID (works for Alembic instances and VRayInstancer source objects ).

Blend color and texture – When enabled, the alpha of the sub-textures is used to blend between the color for the respective material ID and the texture color. When disabled, the texture alpha is returned directly and the color specified in the VRayMultiSubTex texture itself for the given material ID is ignored.

Default Color – A default color or texture for objects without Object IDs or Face IDs.

Num IDs – Can be used to set the number of sub-textures.

Delete unused – Deletes disabled slots from the list.

ID (1-20) – Specifies a color or a texture to be assigned to the material when it is assigned on a object with the current ID. Note that valid subtexture IDs are in the range of 1-65535, any value outside the range can lead to unpredictable results.

Loop Through Textures – This option works in Face Material ID and Object ID modes. When the faces or objects assigned with VRayMultiSubTex map are more than the sub-textures in the map, the Loop Through Textures option goes through all sub-textures and once they finish, reverts to the first sub-texture, continuing until all faces or objects get a sub-texture. In Object ID mode all objects with an assigned ID different than 0 get a sub-texture. The ones with object ID equal to 0 get the Default color.

Seed – When the mode is set to Random by Name, this parameter allows the user to change the randomization pattern.

MaxScript Access

The VRayMultiSubTex texmaps list can be managed through several exported functions:

addSubtex – Add the specified number of sub-textures.
deleteSubtex – Delete one or more sub-textures. The first parameter is always the index of the first texture slot to delete, the second is the number of textures to delete (if omitted defaults to 1).
deleteUnused – Delete all sub-textures which are disabled from their respective UI button.
texmap_num – Returns the value of the Num IDs parameter.