haroldo-ok/god-of-thunder-genesis

God of Thunder Genesis Port is a work in progress project that ports the 1994 MS-DOS shareware game God of Thunder, originally made by Adept Software, to the Sega Genesis, also known as the Mega Drive. The original DOS source code was released into the public domain in 2020, which is what made a fan port like this legally possible. In the game, the character Thor fights enemies, throws his hammer, collects jewels, and uses magic items while exploring a top down world spread across three episodes. Porting a DOS game to Genesis hardware means replacing every low level system the original relied on. The DOS graphics mode is replaced with the Genesis hardware sprite and tile system, keyboard controls become a three button joypad, level data that used to load from disk files is embedded directly into the cartridge ROM, and the original PC sound hardware is replaced with the Genesis YM2612 sound chip. The project targets SGDK 1.70, the standard C based development kit used for making Genesis homebrew games. Work completed so far includes analysing the roughly 11,500 line original source tree and writing a detailed porting guide covering every system level difference between DOS and Genesis, converting all of the sprite and background tile graphics into Genesis compatible formats, fixing a palette color scaling bug along the way, and porting sixteen core C source files. Those files cover the main game loop, level rendering and screen transitions, movement and combat logic, over forty enemy movement patterns, sprite management, the heads up display, and pickup and magic item handling. This project is aimed at developers who are interested in retro game porting, Sega Genesis homebrew development, or simply curious how the internal systems of a 1990s DOS game map onto console hardware from the same era. The license for the port itself is not stated in what was provided.