The primary objective was to make 3D programming accessible by introducing an object-oriented API, allowing developers to create complex scenes without the intricacies of low-level OpenGL.

OpenGL (OGL) is a low level application programming interface that takes lists of simple polygons and renders them as quickly as possible.

To do something more practical like “draw a house”, the programmer must break down the object into a series of simple OGL instructions and send them into the engine for rendering.

Open Inventor (OI) was written to address this issue, and provide a common base layer to start working with.

OI also included a number of controller objects and systems for applying them to the scene, making common interaction tasks easier.

On the downside OI tended to be slower than hand-written code, as 3D tasks are notoriously difficult to make perform well without shuffling the data in the scene graph by hand.

Unlike Inventor, Performer remained proprietary so that SGI would have the agility to modify the API as needed to keep in step with the latest hardware enhancements.

At some point in the mid-1990s it was realized that there was no good reason that the two systems could not be combined, resulting in a single high-level API with both performance and programmability.

The Open Inventor API is still commonly used for a wide range of scientific and engineering visualization systems around the world for the development of complex 3D application software.

FEI Company was acquired in 2016 by the Thermo Fisher Scientific Materials & Structural Analysis Division, which continues to develop (and support) Open Inventor.