Curling Simulator

A browser-based Olympic curling game with a real physics model — velocity-dependent friction, pivot-slide curl, sweeping, and stone-on-stone collisions — rendered in 3D (Three.js) with a 2D canvas fallback. Play live at davehomeassist.github.io/curling-simulator.

What's here

Path	What it is
src/physics/	The sim core — stone dynamics (stone.js), trajectory integration (trajectory.js), collisions (collision.js), scoring (scoring.js), and the tunable constants (constants.js)
src/game/	Game state machine (state.js), fixed-step loop (loop.js), input bindings (input.js), and shot-challenge definitions (challenges.js)
src/render/	renderer3d.js (Three.js arena, camera rig, ice shader) and renderer2d.js (canvas fallback), plus ui.js for the HUD/drawers
src/ai/	AI opponent — shot evaluation (evaluator.js) and shot search/planning (shotSearch.js)
src/audio/	Procedural audio — rumble, scrape, impact, and crowd ambience, with an optional sample-based path
scripts/calibrate.py, scripts/calibrate_v2.py	Python scripts used to calibrate the friction/curl model against published curling physics benchmarks
.github/workflows/pages.yml	Builds with Vite and deploys dist/ to GitHub Pages on every push to main
docs/PLAYER_GUIDE.md	How to play — controls, shot types, scoring, game modes

How to run

npm install
npm run dev       # local dev server (Vite) at http://localhost:5173
npm run build      # production build to dist/
npm run preview    # preview the production build
npm test           # run the Vitest suite (physics, AI, audio, challenges)

Conventions

• Units: the physics engine works in real-world SI units — metres for position/distance, m/s for velocity, and a 44.5m × 4.75m sheet (src/physics/constants.js) matching regulation curling ice.
• Coordinate system: y runs down the sheet from the hack (y = 0) through the hog line, to the tee line (button, y = 23.47) and back line (y = 29); x is centered on the sheet (0), with the house radius and stone radius also defined in constants.js.
• Calibration: friction/curl coefficients were tuned against published curling physics benchmarks (see VALIDATION_RESEARCH.md and src/physics/validation.test.js) rather than picked arbitrarily.