March’s Program: T.W.M.
Tactical War Machine, a simple animation using ZX81 BASIC.
T.W.M. is March’s program of the month. It is a simple animation that tries to mimic a computer’s destruction of its defined target. February was actually pretty prolific for me as I transcribed this and another program, as well as updated a number of older programs using MCODER. Fortunately, that means I have a few more programs available than I normally do. Of course, one is more than I normally have ready so I’m not sure that means much. Anyway, go give it a try and enjoy the animation in all its simplicity.
And simple is what this program is all about. The first display is a giant print statement. Why you ask? Because it’s fast! Printing line by line isn't much slower, but it is noticeable when printing a large graphic. However, when I wanted it slower, printing line by line wasn’t quite slow enough. In that case, I used some of the math functions like LET L=SIN PI
to slow things down a bit for effect. I also used a simple loop later to pause a for a longer period. Although you can use PAUSE
to add a delay in ZX81 BASIC, it has a couple of drawbacks. First, if you enter a key it will skip the delay. That isn’t always desired. The other reason, and why I didn’t use it here, was that PAUSE
causes a the display to jump which is jarring in a smooth animation. There is a reason for this, which is that PAUSE
displays the screen when in FAST
mode. However, I didn’t need that here. Incidentally, I did use the switching between FAST
and SLOW
to emulate a reset. Nice, huh? The bulk of the rest of program is PRINT
statements. Sometimes the simple programs are the best.
If you want to run this program on your Android phone or tablet you can download a compressed copy of the program to your device. You’ll need to save the .p version of the program to your device to allow Zed Ex (Beta) to run it.