WebXR experiment2025
Polytope XR
A spherical polytope, cut into pieces, reassembled in augmented reality.

A geodesic sphere cut into small pieces, glued back into a few clusters that float in front of you in AR. Grab them with a controller or your bare hands and drag until neighbours snap together; the solved shape settles into a slow spin, then the next level deals it in one more cluster, cut from more pieces, up to sixty pieces in ten clusters at level ten.
What makes it interesting
- The scene graph is driven by a reactive core rather than a frame loop — meshes, materials and geometries are declared as signals and disposed automatically when they fall out of the graph.
- The status panel is ordinary DOM, authored as HTML and CSS and projected into the scene, so a controller ray landing on a button arrives at the markup as a click: written once, and working with a ray, a hand or a mouse.
- Every piece is a cone from the centre of the sphere out through its surface, around one of a set of evenly spread directions, so each one carries some of the coloured shell. A level glues neighbouring cones into clusters of about the same size, so no cluster is the clean half a single plane would leave.
- Subdivision and the merge test are pure geometry, kept apart from the scene and property-tested with fast-check.
More pictures

Level 4: twelve pieces dealt as four clusters, grey wherever the cuts went through.