DashGeometry

A browser-based Geometry Dash–style game built with vanilla JS and HTML5 Canvas.

How to Play

Open index.html in any modern browser. If your browser blocks ES modules from file://, run the folder through any small static server instead, for example npx serve ..

Classic Dash is the default level. To start the second level directly, open the page with ?level=ember-ascent. The browser shell also accepts the legacy alias ?level=jermonji-violet-bridge.

Validate generated level authoring rules with:

npm run check

Action	Input
Jump	Space, ↑, Click, or Tap
Restart	Same as above after death
Start Level 2 by URL	?level=ember-ascent

Hold jump input to automatically jump again on landing.

Avoid spikes, use portals, and reach the end of the level.

File Structure

DashGeometry/
├── index.html          — game shell
├── style.css           — full-screen canvas, dark theme
├── js/
│   ├── main.js         — entry point
│   ├── game.js         — game loop, state machine, collision (Claude Code)
│   ├── config.js       — shared physics, world, and collision constants
│   ├── player.js       — physics: gravity, jump, AABB (Claude Code)
│   ├── level.js        — generated level catalog, themes, camera scroll (Claude Code)
│   ├── levelBuilder.js — reusable level motif helpers
│   ├── levelRules.js   — physics-derived spacing and validation rules
│   ├── renderer.js     — canvas draw calls, parallax, themed portals (Claude Code)
│   └── input.js        — keyboard/mouse/touch handler, level switching (Copilot CLI)
└── scripts/
    ├── validate-level.mjs — generated level validation command
    ├── smoke-portals.mjs — portal linkage smoke test
    ├── smoke-runtime.mjs — headless runtime portal smoke test
    └── orchestrate.sh    — ACP delegation wrapper

Multi-Agent Build

This project was built using a three-agent ACP coordination workflow:

Agent	Tool	Task
Claude Code	claude	Orchestrator — game engine, physics, renderer
Copilot CLI	gh copilot -p	js/input.js input handler
Codex CLI	codex exec	README.md, .gitignore

The delegation uses Copilot CLI's non-interactive -p flag and Codex CLI's exec subcommand as ACP-style subprocess calls. True ACP wire protocol (JSON-RPC 2.0 over NDJSON via gh copilot --acp) is deferred as a follow-up enhancement.

Physics

• Gravity: 0.58 px/frame²
• Jump force: −13.2 px/frame
• Player speed: 3.2 px/frame (≈192 px/sec at 60 fps)
• Level 2 speed: 3.6 px/frame
• Jump buffering: 6 frames
• Portal cooldown: 16 frames
• Tile size: 40 px

Level Authoring Rules

• Same-lane spikes must be at least 4 tiles apart.
• Elevated spikes must be fully supported by a block underneath.
• Elevated platforms are limited to one spike at the first-level difficulty.
• Portals must reference a valid paired exit and sit on supported ground or platforms.
• Stair platforms use 9-tile runs with 1-tile approach gaps.
• Levels are generated from reusable motifs and validated when level.js loads.
• Movement is frame-scaled against a 60 FPS target so timing is more consistent across devices.
• Spike collision uses an inset triangle hitbox rather than a rectangular proxy.
• Press L on menu, win, or death screens to switch between levels.
• Unknown ?level= values fall back to Classic Dash.