Grime is an old DOS top-down shooter game, developed by Mark Elendt and released in 1984.
GrimeZ80 is a re-creation for 8-bit computer systems based on the Z80 processor. It has been written to be cross-platform, running on 11 different systems including the Amstrad CPC, ZX Spectrum, MSX1, MSX2, Enterprise, Sam Coupe, TI-83 calculator, Gameboy, Gameboy Color, Sega Master System, and Sega Game Gear!
It was developed in 2018 over 7-days as part of the ChibiAkumas Z80 programming tutorials, and has been made available here in the hope that others can learn from these techniques to develop their own cross-platform games.
Along with the code itself, there is also a series of videos featuring an overview of the development for each of the 7 days. These can be found on YouTube.
A deadly, all-consuming mold has emerged from the polluted swamp, spawned from toxic chemical waste, and engulfing everything in its path with venomous grime. Go forth in your herbicide-spewing Herbmobile, and destroy the mold colonies which are threatening the town of Spudville.
The game is similar in style to Centipede and its variants, but distinct in some gameplay mechanics. Your vehicle can move throughout the entire playing field, shoot in four directions, and toggle an auto-fire mode. Battle the expanding patches of grime, the mutated wildlife, and the spores that continuously deposit new colonies of mold. [text source: MobyGames]
Keyboard controls:
W - Up
A - Left
S - Down
D - Right
B - Rotate Left
N - Rotate Right
P - Pause
ENTER - resume from pause
Compile the file GrimeZ80.asm with vasm
or an equivalent assembler.
Using vasm Old Style running on a Unix based OS, the game can be compiled
for the ZX Spectrum with the following process:
First, edit GrimeZ80.asm and uncomment line 7 (remove the ;):
BuildZXS equ 1 ; Build for ZX Spectrum
Then type the following commands in your terminal:
$ cd GrimeZ80/Sources
$ vasmz80_oldstyle GrimeZ80.asm -chklabels -nocase -Dvasm=1 -Fbin -o grime.z80 -L grime.txt
To run the game with the FUSE ZX Spectrum emulator:
- Select menu:
File -> Import Binary Dataand load the data to address32768. - In the emulator type:
RANDOMIZE USR 32768.
There is a series of videos discussing this game on the YouTube channel: https://www.youtube.com/playlist?list=PLp_QNRIYljFqwHWKzqpOcYl4bq6RUrvu4
and a summary of how the code works here: https://youtu.be/xNUN43k6XMs
and a small website showing it playing: http://www.chibiakumas.com/z80/grimez80.php
Copyright (c) 2018 Keith Sear