// Tech

Three.js Physics with Cannon-es — Real-Time Simulation

Cannon-es brings rigid-body physics to Three.js scenes — gravity, collision, constraints, rope and cloth simulations.

Cannon-es is the maintained ES module fork of cannon.js, the most-used physics engine for Three.js. It handles rigid-body dynamics (gravity, collisions, restitution), constraints (joints, springs, hinges), and basic cloth simulation. For web 3D projects, physics earns its keep when interactivity drives the experience: a particle field that reacts to mouse, a ragdoll character that responds to drag, a chain link that swings under gravity. For static showcases or simple animations, physics is overkill — direct keyframe animation is cheaper. I default to cannon-es for medium complexity, switch to rapier (Rust-based, faster) for production projects with heavy simulation.

What you get hands-off

After delivery: source repository on GitHub (private), commented code, a 5-min Loom walkthrough explaining the scene logic, and the asset pipeline documented. First year of hosting and minor revisions is included. After that we agree on a maintenance plan if needed.

What this delivers

Concrete output: a working three js physics cannon integration on a real production site, not a demo. The integration includes device-tier detection so weak phones get a lighter version automatically. Source files are handed over in their original formats — Blender, GLSL, glTF — so any future developer can continue where I stopped.

How I work with it

On a typical project, three js physics cannon ships as a self-contained module: one entry-point JS file, one CSS file, asset bundle below 1.5MB total. I keep the integration sandboxed so the rest of the site stays SEO-friendly classical HTML. Frame budget targets 60 FPS on a mid-range Android, with a measurable fallback below.

Performance budget

Lighthouse mobile target: 85+ across all categories. I measure on real devices, not just emulator. Asset compression: glTF + Draco for meshes, KTX2 for textures, Brotli for shaders. Lazy-load any three js physics cannon scene that isn't above the fold so the first paint stays under 1.5s.

Frequently asked questions

Why pick this technology over alternatives?

It has the largest production-quality ecosystem, the most documentation, and the most experienced developers available. For a site you want to maintain for 3+ years, ecosystem maturity matters more than feature peak.

What if a newer tool comes out next year?

I track new tooling and migrate when it makes sense, but only after the new tool ships stable production releases for at least 6-9 months. I don't rebuild client sites on bleeding-edge tools — that's the path to broken sites.

How long does this take?

Standard scope: 4-6 weeks from contract signature to live site. Larger scope (configurator, multi-scene scrollytelling) takes 8-12 weeks. Rush projects (2-3 weeks) are accepted with a 30-40% rush surcharge.

What does it cost?

Hero-section 3D upgrade: \$1,500-\$2,500. Full multi-scene 3D site: \$3,500-\$8,000. Configurator with custom shaders: \$5,000-\$12,000. All fixed-price, source code included. EUR equivalents on request.

What if my visitors are on weak phones?

The site detects device tier before the first scene loads and serves a lighter version on weak hardware (fewer particles, simpler shaders). Devices without WebGL get a static fallback that preserves the visual language and conversion path.

Ready to ship a 3D experience?

Tell me what you need — fixed price, fixed deadline, no surprises.

Get a quote +381 61 224 8989