Recursively moves an existing point to a new position.

@private
@param {Vector3} point - The point.
@param {Vector3} position - The new position.
@param {Octree} octree - The octree.
@param {Octant} octant - The current octant.
@param {Octant} parent - The parent of the current octant.
@param {Number} depth - The current depth.
@return {Object} The data entry of the updated point or null if it didn't exist.
function move(point, position, octree, octant, parent, depth) {

	const children = octant.children;

	let result = null;

	let i, l;
	let points;

	if(octant.contains(point, octree.bias)) {

		if(octant.contains(position, octree.bias)) {

			// The point and the new position both fall into the current octant.
			if(children !== null) {

				++depth;

				for(i = 0, l = children.length; result === null && i < l; ++i) {

					result = move(point, position, octree, children[i], octant, depth);

				}

			} else if(octant.points !== null) {

				// No divergence - the point can be updated in place.
				points = octant.points;

				for(i = 0, l = points.length; i < l; ++i) {

					if(point.equals(points[i])) {

						// The point exists! Update its position.
						points[i].copy(position);
						result = octant.data[i];

						break;

					}

				}

			}

		} else {

			// Retrieve the point and remove it.
			result = remove(point, octree, octant, parent);

			// Go back to the parent octant and add the updated point.
			put(position, result, octree, parent, depth - 1);

		}

	}

	return result;

}