Rigidbody2D.totalForce

描述

自上次物理模拟步骤以来，显式应用于此 Rigidbody2D 的力的总量。

当使用 Rigidbody2D.AddForce、Rigidbody2D.AddForceAtPosition 或 Rigidbody2D.AddRelativeForce 向 Rigidbody2D 添加力时，力的总和将被累加。这仅适用于使用 ForceMode2D.Force 时，不适用于使用 ForceMode2D.Impulse 时。

在下一个模拟步骤中，合力将被时间积分到 Rigidbody2D.linearVelocity 中，然后自动重置为 零。

注意：只有具有 动态刚体类型 的 Rigidbody2D 才会响应力和扭矩。在 运动学刚体类型 或 静态刚体类型 上设置此属性将无效。

using UnityEngine;
using UnityEngine.Assertions;

public class Example : MonoBehaviour
{
    void Start()
    {
        // Fetch the rigidbody.
        var body = GetComponent<Rigidbody2D>();

        // Make the assumption the body has no previous force applied.
        Assert.AreEqual(Vector2.zero, body.totalForce);

        // Initialize a force.
        var force = new Vector2(3f, 2f);

        // Add the force.
        body.AddForce(force);

        // The total force should be what we just added.
        Assert.AreEqual(force, body.totalForce);

        // Add the same force again.
        body.AddForce(force);

        // The total force should still be what we've added.
        Assert.AreEqual(force * 2f, body.totalForce);

        // We can reset any force that has been applied since the last simulation step.
        body.totalForce = Vector2.zero;
    }
}