HDI - Longest Acronym Ever!

Autodesk's HDI is short for Hierarchical Object-Oriented Picture System Extended Immediate-mode Drawing Interface Device Interface.

It turns out that HDI is composed of two other acronyms:

-- HDI is short for HEIDI Device Interface.
-- HEIDI is short for HOOPS Extended Immediate-mode Drawing Interface.
-- and HOOPS is short for Hierarchical Object-Oriented Picture System.

So that's how the three-letter acronym HDI becomes an abbreviation for 12 words.

Comments

[Scott Sheppard]

I was managing HOOPS when Jeff Kowalski and Bob Covey approached me with the HOOPS Immediate-mode Drawing Interface. I said we've got to work an "E" in there, so we can call it HEIDI. I suggested Extensible, and it stuck. The "Immediate-mode" aspect of HEIDI was important because, as designed, HOOPS is a retained graphics system with a graphics database. This was inappropriate for AutoCAD which already had its own database - AcDB. We needed something that would draw very quickly and let the application keep track of the data.