About Showroom

Subway Arts

22 PETSCII Artists - 1 WholeTrain

Credits

Idea, Concept, Design & GFX: Rebel 1
Code & GFX: jmin
GFX & DirArt: t0m3000
Music: TheK
PETSCII Artists: 4gentE, Almighty God, Bass Cadet, Clayboy, Dr. TerrorZ, Duce, Frida Katarina, Guinea_Pig, Honcho, Idfred, jab, LFT, littlebitspace, Lobo, ND, Sande, Shine, tNG, Twoflower

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Load it up!

RESTART | C64 Emulator LVLLVL.com/C64 by James

How it started

First time limiting myself to the coder role only.

The proposed project looked easy and the whole setup was already there when Rebel 1 asked me to join in: A full screen PETSCII (released early as a teaser), but the train should be scrolling through to show three or four wagons.

With what I've learned when coding my parts of the PXP' X'2026 demo, it looked like a doable challenge and I fully committed becoming a "code monkey" and implement whatever ideas R1 and t3K throwing at me in our discord chat, all while cutting my inputs down to a minimum and boy, the chat kept me on my toes :D

Coding along

• Train should move slower > Here you go
• Train should be split up into three shorter ones > Got it
• Let's have Joy2 control for the train > Sure, thought you'd never ask
• Train should move faster > Here you go
• We need lightning flashes > Why not
• Animating the cat > Nobrainer
• Wait, I had VICE at 50%! Make the train slower again > Hehe, yeah
• A booming boom box > OK
• Train should come in fast and then slow down > Here you go
• No, no, Boombox should be in sync! > Oh, okaaay... I'll figure something out...
• Let's show the artists' handles when their wagon scrolls in > Jep, got it.
• TheK added a NY siren so we need to dip the scene in red/blue light > Gotcha.
• Wait, my headphones add lag, let's resync again > Woah, mine too
• Here's 10 more wagons > Whoa, better free up some memory
• How about having a hi-res screen filled with tags at the end > Never done that but it shouldn't be too hard.
• And make those sprayed tags drip > Ha, yeah, ok.
• Let's throw out the Joy controls and sync everything to the music > Jep
• Slimer needs to be animated > OK, syncing that one in somehow.
• Let's add the Berlin S-Bahn > More data 0.O
• We need more flashing text in the infoscreen between the trains > On it.
• Graffiti train should come in a bit earlier > Sure.

I'm exaggerating of course, it was jolly good fun and it matched my own approach perfectly doing tons of iterations (we burnt through 145 versions in ten weeks) mixed with rapid prototyping because, "Change speed from 3 to 4" can indeed only be really compared when seeing them both running. Same for smaller things like the fad-in/out effect of texts and shaving off frames for syncing it to the music by ear (yeah, I'm still doing busy waits instead of IRQs). All in all, it was a smooth production with everybody happy to find and agree on tweaks and variants if something didn't turn out as expected.

Big hurdle

One big hurdle that we've tackled early on: The initial screen would have required multiplexing sprites for the buildings right/left which I just couldn't bring to life without flickering. To solve that, we just expanded the "train window" and thus reduced the number of sprites needed to eight and thus avoiding a lot of headache on my side.

Smaller hurdles

Other not so big hurdles were me reimplementing my scroll routine two times (one just redrew the train from scratch with a shifted pointer instead of copying, the other copied to left/right in memory and only adding a new column at the end) and changing how color data of the PETSCIIs was handled to save memory by "crunching" two values into one byte. Both fun to figure out & code but of course no visible change for the guys to marvel about.

Last hurdle was incorporating two custom charsets while multiplexing sprites. Never done that before but it was rather straight forward: fill the screen with the map exported from CharPad and flip a pointer for showing the two charsets and of course update the sprite pointers three times per frame too. Syncing up the fade-ins and updating the sprite coordinates was just keeping my tables up-to-date. That bit was so satisfying to code.

Creative Inputs

OK, about my "no creative input from my side"-stance. Let's be absolutely honest, there wasn't zero creative input from my side, I did of course join the discussion but only after an idea got sent in by R1 and t3k, e.g. the dripping tags was t3k's idea but the specification didn't go beyond "let some drops run down the screen", so it was a "here's my implementation of that thought"-"that looks cool!" conversation followed by tweaks; same with discussing fad-in/outs and the C64 heart thingy at the end. So, big applause from me to R1 for helming this thing creatively.

Anyway, two things that had in fact been triggered by me were the following:

1) the first wagon R1 sent in had a backed-in reflection and lifting that from the wagon and turning it into a "static" reflection layered onto all wagons on the fly was something I wanted to fool around with right away. It's jiggerish, but then again, it's pure PETSCII and IMHO elevated the wagons even beyond their fantastic designs.

2) adding a hidden part was me too because I wanted to shove the already implemented but later discarded joy2-controls code back into the demo somehow; bringing a high speed train to a full stop felt just too good to be kicked out! Additionally, some artists sent in more than one wagon and not using those would be a waste. We used those as fillers while waiting for other contributions to be sent in, and I decided early on to try keeping them all in memory. That and the joy2 controls later turned into the hidden bonus section. Pretty sure though, finding a way of somehow adding those wagons to the demo would have come from R1/t3k anyway and in this case, I just dropped it on the table before them.

Lastly, the exomizer spray can was my brainfart. t3k asked if I could replace the default "A" character to a "99.9%" or some other text and well, if you can print out numbers and chars, a PETSCII should be possible too!

Conclusio

Anyway, long story short, it was a fun project and working with R1, t3K and TheK was pure bliss. As for all other PETSCII artists joining in, a big thank you! Can't express how those stunning PETSCII art dripping in help me staying motivated to dive into my messy code over and over again these past weeks.

Post party!

Here's a snippet from the party:

And here's Rebel 1 picking up the trophy for 2nd place \o/

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What's CSDb thinking about this production?

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What's Pouet thinking about this production?