Unity中的制作贝塞尔弧线动画
1、场景创建空物体，添加组件“LineRenderer”,并添加材质到组件上
2、再写贝塞尔曲线代码，分了两种方式去表现：
a、DrawLine :这曲线动画利用差值方式运算的
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using UnityEngine;
using System.Collections;
using System.Collections.Generic;
/// <summary>/// 贝塞尔曲线/// </summary>public class DrawLine : MonoBehaviour
{ public int SectionDetail = 100;//段数
public List<Transform> gameOjbet_tran = new List<Transform>();
private List<Vector3> point = new List<Vector3>();
private LineRenderer line;
public GameObject ball;
public float Speed = 1;
public float Time1 = 2f;
private float Timer = 0;
private int i = 1;
// Use this for initialization
void Init()
{
line = GetComponent<LineRenderer>();
point = new List<Vector3>();
for (int i = 0; i < SectionDetail; i++)
{
//第一球
Vector3 pos1 = Vector3.Lerp(gameOjbet_tran[0].position, gameOjbet_tran[1].position, i / 100f);
Vector3 pos2 = Vector3.Lerp(gameOjbet_tran[1].position, gameOjbet_tran[2].position, i / 100f);
Vector3 pos3 = Vector3.Lerp(gameOjbet_tran[2].position, gameOjbet_tran[3].position, i / 100f);
Vector3 pos4 = Vector3.Lerp(gameOjbet_tran[3].position, gameOjbet_tran[4].position, i / 100f);
//第二球
var pos1_0 = Vector3.Lerp(pos1, pos2, i / 100f);
var pos1_1 = Vector3.Lerp(pos2, pos3, i / 100f);
var pos1_2 = Vector3.Lerp(pos3, pos4, i / 100f);
//第三球
var pos2_0 = Vector3.Lerp(pos1_0, pos1_1, i / 100f);
var pos2_1 = Vector3.Lerp(pos1_1, pos1_2, i / 100f);
//第四球
Vector3 find = Vector3.Lerp(pos2_0, pos2_1, i / 100f);
point.Add(find);
}
}
//void OnDrawGizmos()//画线
//{
// //Init();
// Gizmos.color = Color.yellow;
// for (int i = 0; i < point.Count - 1; i++)
// {
// Gizmos.DrawLine(point[i], point[i + 1]);
// }
//}
//------------------------------------------------------------------------------
//使小球没曲线运动
//这里不能直接在for里以Point使用差值运算，看不到小球运算效果
//定义一个计时器，在相隔时间内进行一次差值运算。
void Awake()
{
Init();
}
void Update()
{
Timer += Time.deltaTime;
if (Timer > Time1)
{
Timer = 0;
line.positionCount = i;
line.SetPosition(i-1, point[i]);
ball.transform.localPosition = Vector3.Lerp(point[i - 1], point[i], 1f);
i++;
if (i >= point.Count)
{//结束
i = 1;
}
}
}
} |
b、BesselLine 运用贝塞尔曲线公式实现的
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using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class BesselLine : MonoBehaviour {
public List<Transform> gameOjbet_tran = new List<Transform>();
private List<Vector3> point = new List<Vector3>();
public GameObject ball;
public int SectionDetail = 100;//段数
private LineRenderer line;
public Color StartColor = Color.yellow;
public Color EndColor = Color.red;
public float StartSize = 1.0f;//开始大小
public float EndSize = 1.0f;//结束大小
public float Speed = 1;
public float Time1 = 2f;
private float Timer = 0;
private int i = 1;
void Start ()
{
line = GetComponent<LineRenderer>();
for (int j = 0; j < SectionDetail; j++)
{
float node = (float)j / SectionDetail;
point.Add(Cala(node, gameOjbet_tran[0].position, gameOjbet_tran[1].position, gameOjbet_tran[2].position, gameOjbet_tran[3].position));
}
}
// Update is called once per framevoid Update () {
//大小
line.startWidth = StartSize;
line.endWidth = EndSize;
//颜色
line.startColor = StartColor;
line.endColor = EndColor;
if (SectionDetail < 2)
{
SectionDetail = 2;
}
Timer += Time.deltaTime;
if (Timer > Time1)
{
Timer = 0;
line.positionCount = i;
line.SetPosition(i - 1, point[i]);
// ball.transform.localPosition = Vector3.Lerp(point[i - 1], point[i], 1f);
i++;
if (i >= point.Count)
{//结束
i = 1;
}
}
}
/// <summary>
/// 线性的贝塞尔曲线
/// </summary>
/// <param name="t"></param>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <returns></returns>
Vector3 Cala(float t, Vector3 p0, Vector3 p1)
{//P = P0+ t (P1 - P0)，0 <= t <= 1
return p0 + t*(p1 - p0);
}
/// <summary>
/// 二次贝塞尔曲线动
/// </summary>
/// <param name="t"></param>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <returns></returns>
Vector3 Cala(float t, Vector3 p0, Vector3 p1, Vector3 p2)
{// B(t) = (1-t)^2P0+ 2(1-t)tP1 + t^2P2, 0 <= t <= 1
float u = 1 - t;
float tt = t * t;
float uu = u * u;
float uuu = uu * u;
float ttt = tt * t;
Vector3 p = uu * p0;
p += 2 * u * t * p1;
p += tt * p2;
return p;
}
/// <summary>
/// 三次贝塞尔曲线
/// </summary>
/// <param name="t"></param>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <param name="p3"></param>
/// <returns></returns>
Vector3 Cala(float t, Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3)
{
float u = 1 - t;
float tt = t * t;
float uu = u * u;
float uuu = uu * u;
float ttt = tt * t;
Vector3 p = uuu * p0;
p += 3 * uu * t * p1;
p += 3 * u * tt * p2;
p += ttt * p3;
return p;
}
//void OnDrawGizmos()//画线
//{
// //Init();
// Gizmos.color = Color.yellow;
// for (int i = 0; i < point.Count - 1; i++)
// {
// Gizmos.DrawLine(point[i], point[i + 1]);
// }
//}
} |
3、把上面其中一段代码添加到空物体上面（我这里就放了一个代码）
4、创建4个标志点，然后拖拽到代码“GameObject_Item”里面,运行效果