The new high variant of the o3-mini from OpenAI took only 33 seconds to model this simulation, featuring a hundred colourful balls bouncing inside a rotating sphere. Each ball stores a brief record of its recent positions and draws line segments between them with gradually increasing opacity, creating a graceful fading trail. Collision detection is handled by checking whether a ball’s centre (plus its radius) has moved beyond the container sphere’s boundary, after which its velocity is reflected accordingly. This is seriously impressive stuff.