Autodesk IMX Writer

The Autodesk IMX Writer allows FME to create data files for the Autodesk Infrastructure Modeller application. Primarily this is the storage of 3D data or 2.5D data in an SQLite database with a fixed schema.


IMX is an exchange format for storing 3D objects and 2.5D geometries and attributes in a database format. The IMX writer is built on the FDO framework and as such shares many of the same features and terminology.

The tables contained in the IMX writer correspond to FME feature types.

IMX format supports 3D models with instances, appearances, textures, and representative geometries. These geometries may be written to any of the valid 3D model tables.

Internally, each of the exposed 3D tables, such as buildings, will only contain representative 2.5D bounding boxes or footprints for each instance of a 3D model, with appearances and textures, stored in metadata tables. This allows for efficient storage and sharing of the 3D objects and also the reading of the IMX file as SQLite to see the representative 2.5D geometries.

If 3D data is not provided to the specified 3D tables, then the writer will behave like the SQLite writer in all other cases and aspects.

For more information regarding the underlying FDO architecture, visit

Writer Overview

The writer can create new SQLite-based IMX databases.

If the writer outputs to an existing database, the database will be overwritten.

Commands, such as inserts, updates, and deletes are not currently exposed – all operations result in inserts.