Autodesk 12812-051462-9011 User Guide 3 - Page 1734

NOTE Previous versions of 3ds Max supported multiple materials for polymeshes but only one material ID for each ACIS solid when linking a DWG file, regardless of how many material IDs had been assigned to the solid. Process When 3ds Max links a ACIS solid DWG file from AutoCAD or Revit Architecture (version 2008 and later) with either the Layer, Blocks as Node Hierarchy, Split by Material" or the Entity, Blocks as Node Hierarchy derivation methods, multiple material IDs are read and editable as Multi/Sub-Object materials in the Material Editor. 3ds Max reads each face of a linked ACIS solid to determine if it contains any material IDs that it can read. If more than one material ID is read from a solid, each material ID is translated to a material ID on file link and re-assigned to the object. The program creates Multi/Sub-Object materials only if more than one material ID is found; if an ACIS solid contains only one material ID, a standard architectural material is created and assigned instead. NOTE 3ds Max first evaluates the linked file to find any Revit material IDs, and then looks for AutoCAD material IDs. NOTE If you link a DWG file with the Layer, Blocks as Node Hierarchy, Split by Materials" derivation method, the solid is not split to reflect its materials set. Multi/Sub-Object Material Naming In earlier versions, 3ds Max read the material ID information from the color ID of the AutoCAD/Revit material ID's face. Now, 3ds Max creates a Multi/Sub-Object material for every translated per face material ID each time you link a DWG file that contains an AutoCAD/Revit solid. When the program finds multiple materials assigned to an ACIS solid and creates a Multi/Sub-Object material, it consists of instances of standard architectural scene materials. Naming Conflicts Material IDs are unique within one DWG file. However, the same material ID may appear in two different files, such as Basic Wall: Generic - 12" Masonry. If a naming conflict arises when two scenes are merged, the program applies the last loaded material used in the Multi/Sub-Object material. File Link | 6989