No description
Find a file
WiseDev f5a8c39ab2 stop a crowd shoving troops out of the arena
built a harness first, so the simulation could be run without the client
and the fault seen rather than argued about. it reproduces in twenty
milliseconds what took a battle to observe.

what it showed: a troop on its own walks at the enemy towers and stops
at its range, both sides, correctly. put a lane full of them together
and the ones behind get squeezed backwards past their own towers and
into the edge of the map, where they stand hitting nothing. that is the
y=250 and y=31750 frida read out of the client.

the collision pass was clamped only by the arena, so a troop in a crowd
took a shove every tick with nothing to bound it. it is now limited to
half a step, which is the property that matters: a crowd can slow a
troop but can never carry it backwards faster than it walks.

two smaller ones alongside. bot_play treated every object it owned as a
landmark, so once one of its own troops drifted it played the next card
on top of it and the one after further out again; only buildings count
now. and it deployed exactly on a tower's coordinates, leaving the
collision pass to dig the troop out of a building it was born inside -
it now stands in front. default_target falls back to any enemy when the
buildings on that side are gone.

the harness keeps all of it honest: drop the push bound and a troop is
out of the arena by tick 140.
2026-08-23 17:29:40 +03:00
assets pull the arena tilemaps out of the ipa 2026-08-23 10:13:37 +03:00
config generate the daily card shop server side 2026-08-23 08:47:55 +03:00
crates stop a crowd shoving troops out of the arena 2026-08-23 17:29:40 +03:00
.gitignore nuke the tests and the dead code 2026-08-23 07:51:04 +03:00
Cargo.lock move players and accounts into postgres 2026-08-23 08:40:13 +03:00
Cargo.toml supervised mode: run the services as child processes 2026-08-23 09:46:59 +03:00
LICENSE add MIT license 2026-08-23 09:13:19 +03:00
README.md supervised mode: run the services as child processes 2026-08-23 09:46:59 +03:00

scroll-server

A server for the scroll client (Clash Royale 2.0.1306, iOS). Takes a real client from TCP connect to the lobby: login, own home data, chests, card upgrades, the shop.

Requirements

  • Rust 1.75+
  • PostgreSQL 16

Running

createdb scroll
cargo run --release -p scroll-server

Listens on 0.0.0.0:9339, the port the client hardcodes. The schema is created on first boot. DATABASE_URL defaults to postgres:///scroll.

On macOS a Homebrew cluster may need LC_ALL=C to start at all.

That runs everything in one process. For real isolation, SCROLL_MODE=supervised makes it spawn the three services as child processes and restart any that dies, with backoff:

SCROLL_MODE=supervised ./target/release/scroll-server

They can also be started by hand, in any order:

cargo run --release -p auth-service
cargo run --release -p game-service
cargo run --release -p gateway

Checking it without a phone

scroll-probe speaks the same protocol and prints the decoded lobby:

cargo run --release -p gateway --bin scroll-probe -- 127.0.0.1:9339

Flags: --claim-free-chest, --buy-chest <name>, --desync. Pass an account and pass token to reconnect as an existing player: scroll-probe 127.0.0.1:9339 0 1 <passtoken>.

Pointing a client at it

The client hardcodes game.clashroyaleapp.com. Patch that string in the binary inside the ipa to your machine's address, keeping the 23 byte slot NUL padded so nothing around it moves.

Configuration

variable default
DATABASE_URL postgres:///scroll
SCROLL_MODE single, or supervised
SCROLL_BIN_DIR next to the running binary
SCROLL_AUTH_LISTEN 127.0.0.1:9401
SCROLL_GAME_LISTEN 127.0.0.1:9402
SCROLL_GATEWAY_LISTEN 0.0.0.0:9339
SCROLL_CSV_ROOT assets
SCROLL_SHOP config/shop.json
SCROLL_STARTER_PROFILE built in
RUST_LOG info

Shop

config/shop.json lists what the server sells, as Name#count:

{
  "offers": [
    { "id": 1, "give": "Gold#1000" },
    { "id": 5, "give": "chest:Gold#1" },
    { "id": 7, "give": "Diamonds#500", "cost": "Gold#20000" }
  ]
}

Names resolve against the csv tables. cost is optional; without it the server charges the same price the client computes from the game data.