rabbitc64/README.md

Rabbit Scooter — C64

A Commodore 64 port of rabbitroller, the Game & Watch style LCD mini game, written in 6502 assembly (built with the ACME assembler, using the same toolchain and layout as c64-demo).

Rabbits hop toward you on a five-lane road. Steer your scooter left and right to dodge them: a rabbit that reaches your lane is a miss, one that passes in any other lane is a point. Three misses end the round. The spawn rate and the rabbits' speed ramp up with your score, just like in the original.

Controls

Input	Action
Joystick port 2 left/right, or A / D	change lane (auto-repeats while held)
Fire (or SPACE)	start / retry

How it works

• PAL frame loop synced by polling the raster beam (no interrupts), one state update per frame — intro, menu, play and game over are updvec states. Boot shows the giant TTG / Teletype Games logo with the gold color wash from the c64-demo; the menu and the game over screens are full-screen cards on black — big block-letter titles, fire = start game on the menu, the final score and fire = retry after a loss.
• The background is raster-split at the horizon: sky above, grass below. The road is a grey wedge of inverse-space characters between painted white edge lines, with trees along both shoulders.
• The player is hardware sprite 0; up to seven rabbits live on sprites 1–7. Rabbits follow the road's perspective: a linear y ramp and a t² horizontal fan-out, both precomputed into tables at assembly time (tables.asm). Far rabbits use small sprite frames, near ones switch to big frames and finally to double-sized expanded sprites.
• Random lanes and speeds come from an 8-bit LFSR stirred with the free-running CIA timer.
• Sprite art sits below $1000 so the VIC never sees the character ROM shadow instead of it.

Files

File	Contents
main.asm	BASIC stub, init, frame loop, state dispatch
defs.asm	registers, constants, zero page, macros
intro.asm	boot screen: giant TTG logo with the gold wash
title.asm	full-screen menu: big logo, start game, hopping rabbits
play.asm	gameplay: input, spawning, scoring, HUD
over.asm	full-screen game over: big title, score, retry
common.asm	shared routines: printing, road, input, RNG, rabbit positioning
tables.asm	assembly-time perspective and speed tables
sprites.asm	sprite art (scooter, 4+4 rabbit frames)

Build & run

make deps        # macOS: brew install acme vice
make build       # -> rabbit.prg
make run         # build + launch in VICE (x64sc)

The same targets are available as VS Code tasks. A test build that boots straight into gameplay: acme -DAUTOPLAY=1 -f cbm -o test.prg main.asm.