AutoCAD Inventor :: Detecting If Component Occurrence Is Virtual Component

II need a way to tell if a component occurence is a virtual component.

I'm using a For Each loop to cycle through all of the components in an assembly, and if the component is itself an assembly to set the LOD to "Custom". I'm using the definition document descriptor object for this. It all woks fine until the loop comes across a virtual component which doesn't have a definition document, so I need a way to check if the component is virtual and needs to be skipped.Here's the

Option ExplicitImports Inventor.LevelOfDetailEnumSub MainiLogicVb.UpdateWhenDone = TrueDim doc As AssemblyDocumentDim oLOD As LevelOfDetailRepresentationDim oAsmCompDef As ComponentDefinitionDim oComp As ComponentOccurrenceDim oComps As ComponentOccurrencesdoc = ThisDoc.DocumentIf.
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