No description
Find a file
WiseDev 054321ad50 simulate movement, targeting and damage on the server
crowns now move because the server finally hurts things. each tick it
retargets, moves, resolves attacks and buries the dead, in that order.

the numbers are the client's own. Speed is position units per tick, so a
knight at 60 covers 1.2 tiles a second; SightRange and Range are in the
same units with 1000 to a game tile, and the target's CollisionRadius is
added on the far side of both. distances compare squared with the
client's saturation rule - beyond 46340 on either axis, or on overflow,
the distance is INT_MAX rather than a wrapped negative. the attack timer
counts milliseconds fifty at a time and fires once LoadTime + HitSpeed
have passed, then rewinds to LoadTime. tower damage comes from
projectiles.csv, not from the Damage column of buildings.csv, which is
empty for them.

a princess tower leaving the board is struck from leader_towers, which is
what getStars reads, so crowns follow from the same list the client
keeps.

what is deliberately not modelled yet: pathfinding, so units walk
straight at their target instead of along the roads and over the bridges;
collision, pushback and avoidance; projectiles as travelling objects,
since the damage lands the moment the attack fires; and buffs. field_48
on the combat component is renamed hit_timer after what it holds.
2026-08-23 13:10:30 +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 simulate movement, targeting and damage on the server 2026-08-23 13:10:30 +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.