Models (C++)

This article contains speculation that needs to be confirmed.

There are several representations of a model in Source:

Model index

An integer unique to each model. Same on all clients as the server. Acquired from the return value of PrecacheModel() on the server and after that CBaseEntity::GetModelIndex() on both client and server.

model_t

A handle to an internal engine representation of a model. Can be passed to engine functions, but does nothing on its own. Shared between all instances of a model.

CStudioHdr

A MDL file mapped to memory...but each entity has a different one? Can be queried for all sorts of data, but not modified. Despite being an engine class all source code is in the mod SDK.

ModelInstanceHandle_t

Client-side handle to a model instance. Used by the model rendering system.