Adventure Game Interpreter

From AGI Wiki
Jump to: navigation, search

Adventure Game Interpreter

AGI was written in the early 1980's for Sierra On-Line to create a new revolutionary game for IBM's then new computer system, the PCjr. The game, was King's Quest I, written by the now famous in the computer games world' Roberta Williams.

Utilizing all 16 colors of the EGA graphics adapter, the AGI system allowed players to play an interactive adventure game with text, graphics, and 3-voice sound and music. Since Kings Quest there have been many more games created by Sierra - Space Quest I, Police Quest I and Leisure Suit Larry I to name a few.

In late 1997, the system was nothing but a nostalgic memory of older computer gamers, until it was 'hacked' into by these fans, and 'decoded'. By 1998, a full AGI editor was available. This utility was called AGI Studio, written by Peter Kelly. Now fans were able to create their own adventure games with the ease of this program and use the AGI Interpreter to run them.

Since then, many fan-made games are now available and an SCI editor is also available. SCI was the next generation interpreter after AGI. One of the last AGI games that was created before SCI became the standard was King's Quest 4.


The AGI Specifications are a set of documents, written by the people who figured out the AGI formats. detailing how the data for an AGI game is stored and how the interpreter works. This data includes the logic, picture, view, and sound resources, the WORDS.TOK file and OBJECT file, the directory files and the VOL files.

As indicated in the following excerpt from the AGI Specs, they are not really intended for a game author. To learn how to program AGI, see Logic language.

AGI specs is intended for people writing AGI programs such as editors, viewers and interpreters. It is not supposed to be a beginners' introduction to AGI, or a Logic programming guide for those who just want to create games (although it can serve as a reference for more advanced Logic programmers). If you want to learn the Logic programming language, we suggest you read the logic section of the AGI Studio help file, and the various other bits of documentation and tutorials available on-line. The programming info contained in this document is mostly from the AGDS package and uses different syntax and terminology for the language and can be confusing if you are using AGI Studio for your programming.

There have been three major revisions to the AGI Specs, and it is known that there are errors in the documentation as well as omissions that were accidentally made between versions 2 and 3 of the specs.

AGI Resources











See Also