Stacked on #4243 (the `perf:client` harness) — first step of fixing the every-100ms main-thread stutter: make the per-tick burst small before spreading what remains across frames. ## Problem The harness showed the main-thread burst was dominated by `structuredClone` of the `updates` object, and the clone was dominated by two kinds of per-tick churn that re-sent object payloads every tick: - `gold` / `troops` / `tilesOwned` change for nearly every alive player every tick → ~278 partial `PlayerUpdate` objects per tick (world/400 bots), ~508 on giantworldmap. - Attack troop counts tick down every tick → whole `outgoingAttacks`/`incomingAttacks` arrays re-cloned for every fighting player every tick. - `playerNameViewData` (an all-players record) was cloned every tick but only recomputed every 30 ticks. ## Change Three additions to the worker → main protocol (all transferable, zero-clone): 1. **`packedPlayerUpdates`** — `[smallID, tilesOwned, gold, troops]` float64 quads for players whose stats changed. These fields no longer appear in `PlayerUpdate` diffs (first emissions still carry the full snapshot). Gold is exact in a float64 (game values ≪ 2^53). 2. **`packedAttackUpdates`** — `[ownerSmallID, direction, index, troops]` quads. Attack arrays are only resent when membership/order/retreating changes — which is exactly the condition that keeps the patch indexes valid (a tick either resends an array or patches it, never both). 3. **`playerNameViewData` is now optional** — attached only on placement-rebuild ticks (spawn ticks, first ticks, every 30th, spawn end). The client keeps the last applied values; dead players' name placements freeze at death (matching the previous effective behavior). On the client, `GameView.populateFrame` now also rebuilds `names` / `relationMatrix` / `allianceClusters` only when their inputs changed that tick — field presence on a partial `PlayerUpdate` marks them dirty. (`playerStatus`, nuke telegraphs, and attack rings still recompute every tick; they're tick- or unit-dependent.) ## Results (perf:client, this machine; low-end devices ~5–20× slower) Default run (world, 400 bots, 1800 ticks): | stage | before | after | |---|---|---| | clone (serialize+deserialize) | 1.02ms | **0.09ms** | | GameView.update | 0.62ms | **0.29ms** | | WebGLFrameBuilder.update | 0.04ms | 0.04ms | | **TOTAL burst mean** | **1.67ms** | **0.42ms** | | TOTAL p99 / max | 3.47 / 10.3ms | **1.21 / 3.92ms** | giantworldmap/600t: 2.54 → 0.68ms mean. Player update objects: 278 → 6.5 per tick (world), 508 → 12 (giant). The remaining burst is mostly tile apply + per-tick derivations — the part that frame-spreading (next step) addresses. ## Verification - **Sim final hash unchanged** on all three reference configs (`5607618202213430`, `29309648281599524`, `39945089450032050`) — no simulation behavior change. - **View hash unchanged** on all three configs (`942106e9`, `a3aae227`, `cbaaf265`) — the rendered view state is provably identical tick-for-tick, including the name-freeze semantics. - New tests: `tests/PackedPlayerUpdates.test.ts` (drain + GameRunner cadence), packed-channel and freeze-at-death cases in `tests/client/view/GameView.test.ts`, `packAttackTroopDeltas` unit tests and updated diff contract in `tests/GameUpdateUtils.test.ts` / `tests/PlayerUpdateDiff.test.ts`. - `npm test` (1490 tests), `eslint`, `prettier`, `tsc --noEmit` all pass. 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
OpenFront.io is an online real-time strategy game focused on territorial control and alliance building. Players compete to expand their territory, build structures, and form strategic alliances in various maps based on real-world geography.
This is a fork/rewrite of WarFront.io. Credit to https://github.com/WarFrontIO.
License
OpenFront source code is licensed under the GNU Affero General Public License v3.0
Current copyright notices appear in:
- Footer: "© OpenFront and Contributors"
- Loading screen: "© OpenFront and Contributors"
Modified versions must preserve these notices in reasonably visible locations.
See the LICENSE for complete requirements.
For asset licensing, see LICENSE-ASSETS.
For license history, see LICENSING.md.
🌟 Features
- Real-time Strategy Gameplay: Expand your territory and engage in strategic battles
- Alliance System: Form alliances with other players for mutual defense
- Multiple Maps: Play across various geographical regions including Europe, Asia, Africa, and more
- Resource Management: Balance your expansion with defensive capabilities
- Cross-platform: Play in any modern web browser
📋 Prerequisites
- npm (v10.9.2 or higher)
- A modern web browser (Chrome, Firefox, Edge, etc.)
🚀 Installation
-
Clone the repository
git clone https://github.com/openfrontio/OpenFrontIO.git cd OpenFrontIO -
Install dependencies
npm run instDo NOT use
npm installnornpm ibut instead use ournpm run inst. It runs the safernpm ci --ignore-scriptsto install dependencies exactly according to the versions inpackage-lock.jsonand doesn't run scripts. This can prevent being hit by a supply chain attack.
🎮 Running the Game
Development Mode
Run both the client and server in development mode with live reloading:
npm run dev
This will:
- Start the webpack dev server for the client
- Launch the game server with development settings
- Open the game in your default browser (to disable this behavior, set
SKIP_BROWSER_OPEN=truein your environment)
Client Only
To run just the client with hot reloading:
npm run start:client
Server Only
To run just the server with development settings:
npm run start:server-dev
Connecting to staging or production backends
Sometimes it's useful to connect to production servers when replaying a game, testing user profiles, purchases, or login flow.
To replay a production game, make sure you're on the same commit that the game you want to replay was executed on, you can find the
gitCommitvalue viahttps://api.openfront.io/game/[gameId]. Unfinished games cannot be replayed on localhost.
To connect to staging api servers:
npm run dev:staging
To connect to production api servers:
npm run dev:prod
🛠️ Development Tools
-
Format code:
npm run format -
Lint code:
npm run lint -
Lint and fix code:
npm run lint:fix -
Testing
npm test
🏗️ Project Structure
/src/client- Frontend game client/src/core- Deterministic game simulation/src/server- Backend game server/resources- Static assets (images, maps, etc.)
🤝 Contributing
Contributions and translations are welcome! See CONTRIBUTING.md for the workflow, the approved-issue process, project governance, and translation info.