Three.js Weather

Weather fails in two ways: the particles miss the camera entirely, or every state is a separate system that shares nothing. Both are avoidable.

Pairs with threejs-landscape for the ground it falls on, and threejs-towers for something to fall against.

Anchor the volume in the frustum

The first version of any rain system puts a world-sized box of particles around the origin and looks empty. With a long lens the camera sees a narrow cone, so almost every drop is off-camera.

Build a small volume and carry it in front of the camera, facing the way the camera faces: