import { three } from "https://deno.land/x/remapper@3.0.0/src/deps.ts";
const { Curve } = three;
Returns a unit vector tangent at t. If the subclassed curve do not implement its tangent derivation, 2 points a small delta apart will be used to find its gradient which seems to give a reasonable approximation getTangent(t: number, optionalTarget?: T): T;