Submission #9073: EZGames69's ZXS Jetpac in 10:46.34

(Link to video)
ZX Spectrum
(Submitted: Jet Pac)
baseline
BizHawk 2.9.1
32369
50.080128205
19311
PowerOn
Jetpac (1983)(Ultimate).tzx
Submitted by EZGames69 on 5/17/2024 2:09:13 PM
Submission Comments
Jetpac is a 1983 shooter game for the ZXSpectrum. It was the first game to be developed by "Ultimate Play The Game", which would later become more well known as "Rareware". This game was also included as a playable minigame in Donkey Kong 64 (which was infamous for being required to obtain the rareware coin to beat DK64).

Game objectives

  • Emulator used: BizHawk 2.9.1
  • Uses 16K ZXSpectrum (don't think it works on 128K)

Comments

The levels themselves are pretty straightforward. You fly around on a single screen with 3 platforms while avoiding and shooting enemies, and you put pieces of your rocket ship back together then gather fuel to traverse to the next level. There are about 4 different rockets in the game and you get a new one after 4 levels. I went with the same goal as the previous submission of this game, which goes through all 4 rockets in the game on 16 loops.
I've mostly been putting off this game since the manipulation can be rather tedious. Almost every action you do in the game, as well as every button that's pressed (which also includes the other controllers) affects some of the behavior. One of which is the location of where a fuel tank spawns, as well as how long it takes to show up. I did a ton of random button presses on the other controllers to try an manipulate it to the closest point I could get. There's also the fact that when you hover over the rocket, whatever item you're holding will automatically fall down to it but will be very slow, so I tried to get as low to the rocket as possible to minimize the fall time. I do sometimes delay moving over the rocket to drop fuel since this can also affect the timing of the next fuel drop.
I also try to kill most if not all enemies on screen before entering a rocket since having less sprites on screen significantly reduces lag, as they don't respawn once you enter. I didn't do all of them for the first couple of screens but it'd be difficult to go back and redo those levels. I also found out later on that I can prevent the purple enemies from spawning through the same arbitrary button manipulation, which is nice because not only would it speed up the gameplay sections but also would be less enemies I need to shoot at the end.
Overall this was a pretty tedious game to work on, I don't think what I did here was perfect and there's certainly some room for improvement. However I imagine it might take some decompiling work as well as some botting to really squeeze out more frames, which I am not opposed to someone doing that in the future. For now, this can be used as a baseline for a more optimal strategy. Regardless, I'd like to thank Technoturnovers for making the previous submission for this game, and DigitalDuck who provided some useful information for this game.

nymx: Claiming for judging.
nymx: Ok...this is the work that I needed to see in the previous submission. The routing is possible by the RNG manipulation, which perfectly drops fuel and allows for the fastest refueling of the rocket.
I'd like to say thanks for originally asking me to help out with this, but I am glad to see that you finished it. The manipulation here is among some of the hardest, and I personally witnessed this when I decided to drop out on your offer. Great job with this.
Accepting.

despoa: Processing...
Last Edited by despoa 11 days ago
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