For the UDG question there's an easy way: make 2 UDG sets and you can choice the one you want in every moment with a simple POKE.
A downloadable game
My version of TRON written in BASIC on the ZX Spectrum.
TRON is copyright (C) Disney. I have used their ideas in my game, but I'm giving this away for free and it's for a nearly 40 year old computer, so I really hope they allow me to keep this here. No breach of copyright intended.
I created this game in 2016 for a programming challenge on a facebook group called "BASIC on the ZX Spectrum."
My version features:
- Loading screen
- 4 players, up to 2 of which can be humans playing on the same keyboard.
- The ability to hold down two direction keys and to move in a diagonal fashion
- A custom font
- Different starting positions
- Fancy screen clearing and animation effects
- Explosions when players crash.
Note: Due to the game using all of the original 48K Spectrum's user defined graphics (UDG) characters the game will not work on the 128K Spectrum computers as they took away 2 of the UDGs to replace with the keywords SPECTRUM and PLAY. I'm sure there's a way to get around this, but I'm not sure what that is.
I would suggest running in an emulator and cranking up the emulation speed by a few 100%, as otherwise it is a little slow.
This emulator tape file will play in most modern browsers.