Destiny Hunter for PET (and other 8-bits)

voidstar78 · February 5, 2022

Hello! Last year, over Spring Break, I created Destiny Hunter for the Commodore PET. (then later ported it to Apple2, TRS-80, C64, and IBM PC)

I think it may also be the only game where the ending has a Haiku (well, perhaps some text-adventure has one, I'm not so well versed about those)

The prebuilt binaries are available at my site: (source is all in github as well)

www.destinyhunter.org

Destiny Hunter

The "graphics" do use the native PETSCII symbols. Because of that, the game is really meant for the PET. But I ported it (as best I could) to the Apple2, TRS80 Model 3, as well as color versions for the C64 and IBM PC. Also added sound and gamepad support (for some of the ports - for the PET, I support the same gamepad upgrade that PETSCII Robots uses; for the C64 version I never got back around to finishing proper sound support - I do regret that, but I've had to move on to a lot of other projects since then).

For the Apple2 port, that system (stock) doesn't have a clock. The timing is just throttled by how much game-logic that little processor can handle. On the PET system, there is a "jiffy counter" that can be monitored to measure elapsed time (to decide rate-of-fire and creature movement speeds) -- although the Apple2 also uses a 6502, the integrated system doesn't provide a way to do this, at least not that I could determine with the time I had -- not without an add-on card. Still, the timing works out on the Apple2 build of this.

The TRS80 Model 3 port had its own challenges in adapting to a 64x16 screen (instead of 40x25). I did this by moving all the player-status (that was on top/bottom part of the screen in the original version) over past the 40th column, using that column 41-64 space. You still lose 5 rows of space for the map, but it's the best compromise I could come up with. It's curious to me that the original IBM 5100's also used that 64x16 text resolution - I've wondered if 64x16 was the dimensions of some old punch cards (so it was a carry over from that, perhaps?)

Both the Apple2 and TRS80 have excessive spacing around their native font, so the game unfortunately just doesn't look as nice on those systems (compared to the PET).

The IBM PC port was challenging because the text screen symbol and color attribute bytes are interposed (instead of just two independent memory maps). One thing I learned here, that I hadn't realized before: IBM PC MDA (monochrome) didn't support a 40-column mode, only 80. The 40-column mode was a CGA text mode, which wasn't available until a little bit later after the 1981 IBM PC release (the system supported it, but the hardware wasn't available yet). I was aiming for something that could have been available on the IBM PC launch in late '81 (their actual "launch title" was Microsoft Adventure!!), but it ends up my 40-column color version actually couldn't be "experienced" until maybe 1983.

Anyway, my real focus was on supporting the Original 1977 Trinity - everything else is just a for-fun stretch goal. I didn't quite reach that goal for the TRS-80 Model 1 and had to settle on supporting the Model 3 (basically the font of the Model 1 is very limiting, and very few of them had 32K - and it wasn't clear if the RAM extension for the model 1 would work with the compiled code I was using). And I haven't verified if the game will run on a 2000-series PET hardware (not many people who have one will power them on, but also they probably don't have 32K). xpet, IIRC, was a bit weird at authentically replicating a 2000-series PET (it's close, but I don't think the ROM was quite right for that vintage). I do think an out-of-the-box Apple2 (with 48K) will work - but I only ran it on the emulator for that, I don't have an old Apple2 anymore.

Three funny bits of trivia:

- Someone owns the destinyhunter.com site and is selling it for >$3000. So, I couldn't get that, but I did get destinyhunter.org . Ha!

- Apparently the (modern) game called Destiny released a new in-game character class called the Hunter, around the time I created my game. And so sadly, searches on Destiny Hunter bring up reviews of that character class. Bugger.

- I had no idea about PETSCII Robot until I was finishing up things with Destiny Hunter. And I had spent all this time supporting the 2-button joystick on the C64 port, then came across the SNES Controller adapter (that works for both the PET and C64), and then learned about PETSCII Robot. As it so happened, I got the honor of meeting the legendary 8BitGuy since he's not that far away from me! What are the odds that the universe would conspire to have two guys independently create new-software for a vintage PET system, at roughly the same time, and they live in roughly the same county? Spooky. That said, the work Dave put into PETSCII Robot is absolutely-absolutely outstanding and heads and shoulders above my own (especially also his dedication to the art of pure assembly, whereas my work is compiled C code -- although with a few bits of inline assembly!! -- and very clever use of PETSCII art).

PETSCII Robot is incredible because of the background music and off-screen AI handling - it really is a hand-crafted miniature OS there. Although, at least in my game, I was able to pull off the firing breathing hydra! Honestly that's sort of how this project started: the vision of that 3-headed dragon in the original NES Zelda came to me (end boss of one of the dungeons), and I wondered if the PET could replicate that experience. I got a little close at least (sans-dragon neck tho ).

BTW, info on that GamePad adapter:
https://texelec.com/product/snes-adapter-commodore/
(only trick is you do need to add a 5v supply - for the PET, I requested them to send me an extra header to easily plug in and get 5v from the secondary tape port, but on the C64 it's a little more tricky)

I do have in mind another game for the PET - I think it's going to be great, but it is going to need a disk drive (or that SD-emulator). Secret for now!! I've been mulling it over in the back of my head this past year. Perhaps this Spring Break I'll get another chance to hammer it out! I'll give one hint about it: the idea was actually inspired by Phil Katz (of PKZIP).

Cheers!

v*

Edited February 5, 2022 by voidstar78
clarify web link