猫史档案馆

async function fromTo(entity = new Box3Entity, to = new Box3Entity) {
    var Quat = new Box3Quaternion(0, 0, 0, 1).rotateZ(Math.PI / 2).rotateX(Math.PI / 2);//初始角度，自行调整
    var w = entity.player.addWearable({
        mesh: 'mesh/箭头.vb',
        offset: new Box3Vector3(0, 1.2, 0),
        scale: new Box3Vector3(1 / 3, 1 / 3, 1 / 3),
        bodyPart: Box3BodyPart.HEAD,
    })//穿戴“箭头”
    var t = world.onTick(() => {
        var p = entity.position.sub(to.position);
        var angle = (
            Math.atan2(p.z, p.x)
            +
            Math.atan2(entity.player.facingDirection.x, entity.player.facingDirection.z)
        );//旋转角度
        w.orientation = Quat.rotateX(angle);
        if (entity.position.distance(to.position) < 2) {//到达终点判断
            entity.player.directMessage('已到达');
            w.remove();
            t.cancel();
        }
    })
}

entity是玩家，to是目标实体，实现功能为玩家头顶的箭头一直指向目标

（只做了平面，三维可以同理）