В скрипте Test я вызываю функцию findClosestTransform из класса Grid:

void FixedUpdate () {
        Vector3 point = Camera.main.ScreenPointToRay(Input.mousePosition).GetPoint(1);
        Transform tr2 = GetComponent<Grid>().findClosestTransform(point);
        tr.position = tr2.position;
    }

Но Юнити выдает ошибку:

public Transform findClosestTransform (Vector3 point) {

        Transform[] closest = new Transform[9];

        foreach (Transform tr in b1row) {
            if (tr == b1row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[0].position, point)) closest[0] = tr;
        }

        foreach (Transform tr in b2row) {
            if (tr == b2row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[1].position, point)) closest[1] = tr;
        }

        foreach (Transform tr in b3row) {
            if (tr == b3row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[2].position, point)) closest[2] = tr;
        }

        foreach (Transform tr in b4row) {
            if (tr == b4row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[3].position, point)) closest[3] = tr;
        }

        foreach (Transform tr in b5row) {
            if (tr == b5row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[4].position, point)) closest[4] = tr;
        }

        foreach (Transform tr in b6row) {
            if (tr == b6row[0] || Vector3.Distance(tr.position, point) < Vector3.Distance(closest[5].position, point)) closest[5] = tr;
        }

        Transform result = closest[0];

        foreach (Transform tr in closest) {
            if (Vector3.Distance(tr.position, point) < Vector3.Distance(result.position, point)) result = tr; // <- В ЭТОЙ СТРОЧКЕ
        }

        return result;

    }

Ошибка:

NullReferenceException: Object reference not set to an instance of an object
Grid.findClosestTransform (Vector3 point) (at Assets/Scripts/Grid.cs:62)
Test.FixedUpdate () (at Assets/Scripts/Test.cs:10)