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+# Rabbit Scooter — C64
+
+A Commodore 64 port of [rabbitroller](../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](../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 | 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 — title, play and game over are `updvec` states.
+- 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 |
+| `title.asm` | title screen: logo, parked scooters, demo rabbits |
+| `play.asm` | gameplay: input, spawning, scoring, HUD |
+| `over.asm` | game over box + 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`.