// Tech

Three.js AnimationMixer — Playing Skeletal Animations

AnimationMixer plays animations baked into glTF files — walk cycles, idle animations, custom rigs from Blender or Maya.

AnimationMixer in Three.js plays animation clips embedded in glTF files. Modeled and rigged in Blender, Maya, or Cinema4D, baked into glTF as keyframe tracks, played in Three.js with crossfade between clips. Common use cases: a character walk-and-idle for portfolio sites, a watch hand sweep for product configurators, a logo unfold animation for hero scenes. The mixer handles blending, timing, and event callbacks (fire something at a specific frame). For complex character animation with state machines (walk → run → jump), I sometimes layer GSAP timelines on top to drive the mixer's time scrubbing — gives more control than the default action API.

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 animation mixer scene that isn't above the fold so the first paint stays under 1.5s.

When this is overkill

If the goal is a simple e-commerce listing or content blog, a full three js animation mixer setup is overkill — a CSS-driven hero plus static images converts just as well at 1/10 the cost. three js animation mixer earns its keep when the brand needs a memorable visual moment or when 3D actually clarifies the product (configurators, tours, demos).

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 animation mixer 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.

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