64 lines
2.9 KiB
Markdown
64 lines
2.9 KiB
Markdown
# doppler
|
|
|
|
A 2-dimensional multiplayer game utilising ray tracing.
|
|
|
|
> **Available at [doppler.schmelczer.dev](https://doppler.schmelczer.dev).**
|
|
|
|
|
|
|
|
|
|
For optimised 2D ray tracing, [SDF-2D](https://github.com/schmelczerandras/sdf-2d) is used.
|
|
|
|
## Development
|
|
|
|
Run `npm install && npm run init` once, then `npm run dev`. Run `npm test` for
|
|
regressions, `npm run lint:check` for formatting and lint, and `npm run build` for
|
|
all production bundles. Tests rebuild the shared library before running.
|
|
|
|
## Movement and networking
|
|
|
|
The server owns physics and combat. It simulates at 200 Hz, keeps each player's
|
|
latest held movement direction, and sends snapshots at 25 Hz. Clients send input
|
|
changes immediately on their next frame and send idle heartbeats at 30 Hz.
|
|
|
|
The local player replays input from the latest authoritative pose using the same
|
|
physics as the server. The acknowledgement includes movement state, remaining leap
|
|
cooldown, and the age of the acknowledged input, so the client can align replay
|
|
without synchronizing wall clocks. Nearby planets are included even when offscreen
|
|
because their gravity affects prediction. Replay stops after 400 ms without a fresh
|
|
anchor; only reconciliation corrections are eased over 80 ms. The camera follows
|
|
the displayed player directly.
|
|
|
|
Other objects interpolate snapshots on a server timeline delayed by 100 ms, with
|
|
at most 60 ms of extrapolation. Creation and deletion use that same timeline.
|
|
Remote effects use that timeline too; feedback for the local player is immediate.
|
|
End-of-round slow motion comes from server snapshots and disables local prediction;
|
|
outgoing velocity and projectile fade rates are expressed per wall-clock second.
|
|
When a connection backs up, regenerable state can be skipped; lifecycle messages
|
|
keep their timestamps. The frontend bundles one `gl-matrix` instance so prediction
|
|
and server physics both use JavaScript's full numeric precision.
|
|
|
|
## Deployment
|
|
|
|
CI/CD runs on Forgejo Actions (`.forgejo/workflows/deploy.yml`). On a push to
|
|
`main` it:
|
|
|
|
- builds the static frontend and rsyncs `frontend/dist/` to the `/pages/declared`
|
|
mount on the runner host (the mount keeps its pre-rebrand name), and
|
|
- builds the server image from the root `Dockerfile` and pushes it to the Forgejo
|
|
container registry as `<registry>/<owner>/<repo>-server`.
|
|
|
|
The registry job needs a `FORGEJO_PACKAGE_TOKEN` secret (with package write
|
|
scope) and, optionally, a `CONTAINER_REGISTRY_HOST` variable to override the
|
|
registry host.
|
|
|
|
The website's server list is hardcoded in
|
|
[`frontend/src/scripts/configuration.ts`](frontend/src/scripts/configuration.ts) —
|
|
edit it to add or remove game-server origins.
|
|
|
|
Run the server image locally:
|
|
|
|
```sh
|
|
docker build -t doppler-server .
|
|
docker run -p 3000:3000 doppler-server --name "My server" --playerLimit 16
|
|
```
|