本文实例为大家分享了UGUI绘制平滑曲线的具体代码，供大家参考，具体内容如下
绘制
实现自定义的MaskableGraphic挂载在UGUI的UI节点上
public class UGUIObjectRender : MaskableGraphic
{
/**
* points 为需要穿过的点
* segments 为曲线细分度
* linewidth 为曲线粗细
*/
protected override void OnPopulateMesh(VertexHelper vh)
{
vh.DrawBeziers(points,segments,linewidth);
}
}
需要时用的工具类在后面
二次贝塞尔工具类
using UnityEngine;
namespace ViVi.UIExtensions
{
/**
* Created by vivi on 16/5/11.
*/
public class BezierUtils {
public float P0x;
public float P1x;
public float P2x;
public float P3x;
public float P0y;
public float P1y;
public float P2y;
public float P3y;
public BezierUtils(float p0x,float p0y,float p1x,float p1y,float p2x,float p2y,float p3x,float p3y) {
P0x = p0x;
P0y = p0y;
P1x = p1x;
P1y = p1y;
P2x = p2x;
P2y = p2y;
P3x = p3x;
P3y = p3y;
}
public BezierUtils(Vector2 p0,Vector2 p1,Vector2 p2,Vector2 p3) {
P0x = p0.x;
P0y = p0.y;
P1x = p1.x;
P1y = p1.y;
P2x = p2.x;
P2y = p2.y;
P3x = p3.x;
P3y = p3.y;
}
public float beze_x(float t){
float it = 1-t;
return it*it*it*P0x + 3*it*it*t*P1x + 3*it*t*t*P2x + t*t*t*P3x;
}
public float beze_y(float t){
float it = 1-t;
return it*it*it*P0y + 3*it*it*t*P1y + 3*it*t*t*P2y + t*t*t*P3y;
}
//-------------------------------------------------------------------------------------
public float beze_speed_x(float t)
{
float it = 1-t;
return -3*P0x*it*it + 3*P1x*it*it - 6*P1x*it*t + 6*P2x*it*t - 3*P2x*t*t + 3*P3x*t*t;
}
public float beze_speed_y(float t)
{
float it = 1-t;
return -3*P0y*it*it + 3*P1y*it*it - 6*P1y*it*t + 6*P2y*it*t - 3*P2y*t*t + 3*P3y*t*t;
}
private float beze_speed(float t)
{
float sx = beze_speed_x(t);
float sy = beze_speed_y(t);
return (float) Mathf.Sqrt(Mathf.Pow(sx,2)+Mathf.Pow(sy,2));
}
//-------------------------------------------------------------------------------------
private float beze_length(float t)
{
float LATESTCOUNT = 10000;
int steps = (int) Mathf.Ceil(LATESTCOUNT * t);
if (steps == 0)
return 0;
if (steps % 2 != 0)
steps++;
float halfSteps = steps * .5f;
float nSum = 0;
float n1Sum = 0;
float disStep = t / steps;
for (int i = 0; i < halfSteps; i++ ) {
n1Sum += beze_speed((2 * i + 1) * disStep);
nSum += beze_speed(2 * i * disStep);
}
return (beze_speed(0) + beze_speed(1) + 2 * n1Sum + 4 * nSum) * disStep / 3;
}
//-------------------------------------------------------------------------------------
private float beze_even(float t)
{
float len = t * beze_length(1);
float uc = 0;
do {
float ulen = beze_length(t);
float uspeed = beze_speed(t);
uc = t - (ulen - len) / uspeed;
if (Mathf.Abs(uc - t) < 0.0001)
break;
t = uc;
}while(true);
return uc;
}
private float totallength = -1;
public float getTotalLength(){
if(totallength<0)
totallength = beze_length(1);
return totallength;
}
public Vector2 getPosition(float t){
return new Vector2(beze_x(t),beze_y(t));
}
}
}
