Version: 2018.2
public RigidbodyConstraints constraints ;

説明

Rigidbody のシミュレーションで自由に操作できる軸をコントロールします

By default this is set to RigidbodyConstraints.None, allowing rotation and movement along all axes. In some cases, you may want to constrain a Rigidbody to only move or rotate along some axes, for example when developing 2D games. You can use the bitwise OR operator to combine multiple constraints.

ワールド空間で位置の制約が、ローカル空間で回転の制約が適用されることに注意してください。

//Attach this script to a GameObject.
//Attach a Rigidbody to the GameObject by clicking the GameObject in the Hierarchy and
//clicking the Add Component button. Search for Rigidbody in the field and select
//it when shown.

using UnityEngine;

public class Example : MonoBehaviour { Rigidbody m_Rigidbody;

void Start() { m_Rigidbody = GetComponent<Rigidbody>(); //This locks the RigidBody so that it does not move or rotate in the Z axis. m_Rigidbody.constraints = RigidbodyConstraints.FreezePositionZ | RigidbodyConstraints.FreezeRotationZ; } }