u4-decompiled

HaltedPlayableDOS

Based on Ultima IV

compare all 4 clones

Image of the original game, Ultima IV. This project has no screenshots of its own yet.

Ultima IV (original game, not this project) — Image of the original game, Ultima IV. This project has no screenshots of its own yet.

Links, repository & details

About

Ultima IV: Quest of the Avatar, first released in 1985 for the Apple II, is the fourth Ultima role-playing game and the first in the 'Age of Enlightenment' trilogy, notable for its much larger world and its shift toward an ethically driven, story-focused approach. u4-decompiled is a reverse-engineered, matching decompilation of the DOS/PC port of Ultima IV (AVATAR.EXE and TITLE.EXE, originally ported by James Van Artsdalen), built from disassembled code — mostly C with some assembly, compiled with Microsoft C Compiler 4.00 — that reproduces executables only about 10 bytes different from the originals.

History

The author built the decompilation not to compete with existing Ultima IV remakes, but so people could study 1980s-era coding techniques and algorithms in the reconstructed source.

Requires original assets. Reverse-engineered decompilation of the original PC version executables of Ultima IV.

Additional notes

Trivia: Because file, variable, and function names were lost in the reverse-engineering process, the author had to invent new names for all of them.