One Prompt Makes Claude Fable 5.2 Run three.js Bare: Chibi Anime Is Solid, Realistic Characters Still Stuck

Zondark posted a hands-on test on X. Without attaching any Skill, they gave Claude Fable 5.2 just one prompt: “Make an anime video with three.js.”

First, watch the result.

Zondark's assessment is that hand-coding 3D-to-2D cel-shaded rendering with pure geometry plus trigonometry is extremely hard for realistic anime characters, but it is very good at chibi characters. This result is more specific than “AI can generate video.” three.js is a 3D library for the browser; 3D-to-2D rendering means rendering 3D models into a 2D-animation look. On the pure-code path, chibi characters have natural advantages: exaggerated head-to-body ratios, facial features that can be simplified, and high tolerance for materials and lighting. Realistic characters require handling face shape, eye highlights, hair grouping, skin texture, expressions, and motion; as the number of geometries grows, so do code volume and debugging cost.

In the replies, WenWen said, “Hand-coding it to this level is good enough.” Zondark replied, “Spheres and cylinders are already exhausted; from what I can see, the looks ceiling for pure hand-coded code is welded shut at chibi.”

The model can write three.js—the video already proves that. What is truly hard about realistic characters is modeling and the rendering pipeline. Zondark asks: Has anyone broken through to realistic-style characters with Fable 5.2 using pure code?

Original post: https://x.com/ZondarkAI/status/2121764124875247879

Readers with a development background can look at the geometry combinations, trigonometry, and rendering parameters. Ordinary readers can just look at the result: one prompt can produce a chibi anime video, while realistic characters still need more work.