Hi guys,
I'm new to the forum but want to explain a bit about AGD because I ported AGD to the Acorn Atom.
The Acorn Atom has the same video processor as the Dragon, the 6847.
Jonathan Cauldwell has written a program called Arcade Game Designer for the ZX Spectrum. It's a game creation program with build-in editors. You can define a font, objects, sprites, blocks, screens and add event based script commands describing how the game runs. You can start the game from the menu for testing. The program is written for a ZX Spectrum 48/128KB. It's a nice program with a good engine and a lot of games are written with AGD. If the game is ready, you can save it in a tapefile as stand alone game which runs without the editors. AGD can be downloade here:
https://jonathan-cauldwell.itch.io/arcade-game-designer
Jonathan has also written an editorless compiler running in Windows. This compiler needs 2 files to generate a game: a game engine and a script file. The script file is compiled to an assembler file and merged with the game engine file. A Z80 assembler source file is generated which can be compiled to Z80 code. This is very interesting for porting AGD to the Atom because if I can convert the game engine to Atomic 6502 code and change the compiler to generate 6502 assembler from the script file, you have an assembler file which can be compiled to 6502 code.
The big advantage is that the engine file is system dependent but the game itself, written as a script file, can be easily ported.
So the AGD system consists of:
- an general game engine file with routines to manage the game
- a game specific script file with font-, objects-, sprites-, blocks- and screen data and commands describing the game
The engine file can't be 100% compatible with all ported systems due to resolution-, colour- and memory differences. The script commands however can be 100% compatible so this means to run a game, you have to change the data and compile it for your system.
For now I have a working Acorn Atom port with more than 50 games working. You can see some examples here:
ZX Spectrum version Terrapins:
https://www.youtube.com/watch?v=ea_dsXmjL90
Atom version Terrapins:
https://www.youtube.com/watch?v=Vh4ykI0H0iE&t=53s
ZX Spectrum version Dodgy:
https://youtu.be/pyMmxWgJLTo
Atom version Dodgy:
https://youtu.be/P9hZtE3y31M
A lot of tests of games:
https://www.youtube.com/user/oss003/vid ... subscriber
There are about 150 games written in AGD ready to be ported:
https://spectrumcomputing.co.uk/index.p ... 6&id=20176
At the moment Tony Tompson is writing an AGDX suite in which you can design your tiles, objects, sprites and screens.
You can also write the game scripts and the goal is to compile the game to different systems.
For now a ZX Spectrum, CPC and Acorn Atom port are available and more to come, eg. BBC and Atari.
So if a Dragon port is available, a whole lot of new games are available.
What has to be done to port AGD:
- Write a Dragon based engine
- Change the script compiler to produce 6809 assembler.
If anyone is interested in helping to create a Dragon port, please contact me because there's an AGD group where the AGDX Studio is developed and technical questions can be answered. I must say that it was fun to create an Atom port and the result is a lot of new games.
Greetings
Kees