public static Vector3 MoveTowards (Vector3 current, Vector3 target, float maxDistanceDelta);

参数

current移动的开始位置。
target移动的目标位置。
maxDistanceDelta每次调用移动 current 的距离。

返回

Vector3 新位置。

描述

计算 current 指定的点与 target 指定的点之间的位置,移动距离不超过 maxDistanceDelta 指定的距离。

使用 MoveTowards 成员将 current 位置处的对象移向 target 位置。通过使用此函数计算的位置来更新每个帧的对象位置,您可以平滑地将其移向目标。使用 maxDistanceDelta 参数来控制移动的速度。如果 current 位置相比 maxDistanceDelta 更靠近 maxDistanceDelta,则返回值等于 maxDistanceDelta;新位置不会过冲 maxDistanceDelta。要确保对象速度与帧率无关,请将 maxDistanceDelta 值乘以 Time.deltaTime(或者 FixedUpdate 循环中的 Time.fixedDeltaTime)。

请注意,如果将 maxDistanceDelta 设置为负值,则该函数将返回与 target 相反方向的位置。

using UnityEngine;
using System.Collections;

// Vector3.MoveTowards example.

// A cube can be moved around the world. It is kept inside a 1 unit by 1 unit // xz space. A small, long cylinder is created and positioned away from the center of // the 1x1 unit. The cylinder is moved between two locations. Each time the cylinder is // positioned the cube moves towards it. When the cube reaches the cylinder the cylinder // is re-positioned to the other location. The cube then changes direction and moves // towards the cylinder again. // // A floor object is created for you. // // To view this example, create a new 3d Project and create a Cube placed at // the origin. Create Example.cs and change the script code to that shown below. // Save the script and add to the Cube. // // Now run the example.

public class Example : MonoBehaviour { // Adjust the speed for the application. public float speed = 1.0f;

// The target (cylinder) position. private Transform target;

void Awake() { // Position the cube at the origin. transform.position = new Vector3(0.0f, 0.0f, 0.0f);

// Create and position the cylinder. Reduce the size. GameObject cylinder = GameObject.CreatePrimitive(PrimitiveType.Cylinder); Camera.main.transform.position = new Vector3(0.85f, 1.0f, -3.0f);

// Grab cylinder values and place on the target. target = cylinder.transform; target.transform.localScale = new Vector3(0.15f, 1.0f, 0.15f); target.transform.position = new Vector3(0.8f, 0.0f, 0.8f);

// Position the camera. Camera.main.transform.position = new Vector3(0.85f, 1.0f, -3.0f); Camera.main.transform.localEulerAngles = new Vector3(15.0f, -20.0f, -0.5f);

// Create and position the floor. GameObject floor = GameObject.CreatePrimitive(PrimitiveType.Plane); floor.transform.position = new Vector3(0.0f, -1.0f, 0.0f); }

void Update() { // Move our position a step closer to the target. float step = speed * Time.deltaTime; // calculate distance to move transform.position = Vector3.MoveTowards(transform.position, target.position, step);

// Check if the position of the cube and sphere are approximately equal. if (Vector3.Distance(transform.position, target.position) < 0.001f) { // Swap the position of the cylinder. target.position *= -1.0f; } } }