Site Shadow
A 3D dome whose shadow follows the simulated sun
Move the hour, watch the sky tilt and the dome lean its shadow north.
A small experimental tile. The dome is a low-poly architectural primitive (cylinder base + hemispherical cap) sitting on a flat ground plane. A directional light is positioned from real solar geometry (NOAA-style azimuth/altitude math) given a date, time, and Berlin’s latitude/longitude. The shadow on the ground is the convex hull of the dome’s silhouette projected along the sun ray — analytically exact for one convex caster on flat ground, and it costs zero per frame.
A procedural low-poly robot walks a slow lap around the dome under a “blob shadow” — a simple darkened disc that follows it. AAA mobile-game trick. Skeletal animation for free, render cost effectively nothing.
Drop the Time Simulator widget on this page and scrub the hour: the dome’s shadow rotates around its base and stretches as the sun lowers, the sky tints from cool noon to warm dusk to cool night, the robot keeps walking. When the simulated hour is cleared, the scene falls back to wall-clock time and ticks once a minute.
Built as a prototype for future architectural / 3D-animation pages. The same scene-graph code generalizes to towers, walls, whole site models — and once Mixamo / Godot exports start landing as glTF, replacing the procedural robot with a rigged character is a one-line gltfLoader.load and an AnimationMixer.