Shows a function f: A -> B as a mapping from each domain element x in set A to exactly one codomain element y in set B. The animation steps through inputs x1..x5, draws the arrow to its assigned output f(x), and highlights the Range as the subset of B that actually gets hit (some outputs repeat to emphasize Range ⊆ B).
Pure Canvas2D. Uses a 4-second cycle; active domain element is highlighted while its arrow is drawn progressively along a blocky polyline. Range elements in B glow when they have been produced. Responsive scaling via scale = min(w,h)/240 with 4px snapping for a retro grid aesthetic.