FABLE 64
a c64 demo by XPLSV
for the Assembly 2026 AI coding demo compo
code and music ... claude
vibes ............ mrdoob
platform: C64 PAL, stock. no REU, no fastload tricks,
no precalculated animation data. runs from one file
(fable64.d64 / demo.prg, ~14 KB).
how to run:
real hardware (PAL C64):
LOAD"FABLE 64",8,1
RUN
the demo loops forever; press RESET to stop it.
emulator (VICE recommended, PAL default):
x64sc -autostart fable64.d64
or simply drag fable64.d64 (or demo.prg) onto
the emulator window.
what the little machine does, all realtime:
- 13-part timeline, ~2:20, everything synced to a
125 bpm SID techno track (kick pitch-sweep, acid
bass through the resonant filter, rave stabs
walking Am-F-C-G, claps, snare rolls, a noise
riser into a white-flash drop)
- 3d dot objects (cube / octa / ring / tetra) that
morph continuously, with depth shading, per-part
palettes, beat zoom and char ghost echoes
- jelly distortion: big letters re-rendered every
frame with per-row char displacement on top of a
per-scanline-row fine-scroll raster chain, both
pumped by the kick drum
- kick-synced firework particles with gravity that
fly across every part and never corrupt anything
(all char effects negotiate cell ownership)
- colour plasma, rotozoomer, copper bars, starfield
- giant 5x5 block-letter greetings waving on three
axes at once (vertical sine per column, horizontal
fine scroll, per-row ripple)
- the lower AND upper borders are open: sprites dive
beneath the screen and float above it
- a proper drop: noise riser, one last kick, three
16ths of dead silence, then the whole display
(borders included) flashes white
- runs as an attract loop: after the end card fades
it breathes for a few seconds and starts over
built live by an AI (Claude) pair-programming with
mrdoob, verified frame by frame through an instrumented
emulator pipeline because the AI cannot see a monitor
or hear a SID. every effect in this file was confirmed
from screenshots and memory dumps of the running demo.
greetings to the entire c64 scene - the full list
scrolls by in glorious 40 pixel letters.
xplsv * 2026