This is the classic overhead view "Tron" game from the movie of the same title (motorcycles that leave "wall trails" behind them). If you crash into a wall, your opponent scores a point. The player who first reaches a score of 5 wins.
Controls:
Turn left/right:
Left Player: A/S
Right Player: Cursor left/right (5/8) or N/M
(in one-player mode, human is right player)
Press Space or 0 to start a round
Pause game: P
End game: X
Thanks to Andy Rea for providing ASM plot functions (zx81plot.h), now you can see how they perform in a "plotting" action game. Two more functions were taken from z8048.c written by sirmorris.
@Fruitcake: is there a way to plot in colour using the Chroma Interface? I assume that this would go beyond it's capabilities. [EDIT: Andy's function plots by putting the appropriate graphical character on the screen - so colourising would work in theory, but it wouldn't make much sense. At least there is no way to give both player's trails a different colour.]
P.S. My stardom may be marred a little by the fact that Andy has already done a Tron game a few years ago (Tron Trails), so it seems that I have "re-invented the wheel". But I noticed that his AI logic seems to be a little different from mine, so we can compare our two approaches. Furthermore, I use rotational controls (left/right only) while Andy uses directional steering.
P.P.S. The history behind my game: in 2016 I decided to write a game for XT-class DOS PCs equipped with a Hercules graphics card, since there are so few games that truly support the Hercules card (most 1980s games simply blew up their 320x200 CGA graphics, but very few produced a real 720x348 Hercules screen).
So H-Tron was born (the "H" stands for "Hercules"), written in December 2016 in Borland Turbo C 2.01.
Later I found the great z88dk C compiler for Z80 computers that allowed me to port the game to the ZX81.
