Rigidbody.velocity

Description

刚体的速度矢量。

In most cases you should not modify the velocity directly, as this can result in unrealistic behaviour. Do not set the velocity of an object every physics step, this will lead to unrealistic physics simulation. A typical usage is where you would change the velocity is when jumping in a first person shooter, because you want an immediate change in velocity.

Note: The velocity is world-space.

using UnityEngine;
using System.Collections;

// The velocity in y is 10 units per second.  If the GameObject starts at (0,0,0) then
// it will reach (0,100,0) units after 10 seconds.

public class ExampleClass : MonoBehaviour
{
    public Rigidbody rb;

    private float t = 0.0f;
    private bool moving = false;

    void Start()
    {
        rb = GetComponent<Rigidbody>();
    }

    void FixedUpdate()
    {
        if (Input.GetButtonDown("Jump"))
        {
            // the cube is going to move upwards in 10 units per second
            rb.velocity = new Vector3(0, 10, 0);
            moving = true;
            Debug.Log("jump");
        }

        if (moving)
        {
            // when the cube has moved over 1 second report it's position
            t = t + Time.deltaTime;
            if (t > 1.0f)
            {
                Debug.Log(gameObject.transform.position.y + " : " + t);
                t = 0.0f;
            }
        }
    }
}

注意：Unity 以单位/秒衡量速度。单位通常表示米，但也可以是毫米或光年。Unity 速度还具有定义方向的 X、Y 和 Z 速度。