unity之uv贴图画圆弧，圆弧面，不规则图形

由于最近一直没有时间，所以这篇博客一直没发，下面我说说uv画圆弧，圆面，不规则面拼接。

先来两张效果图





图截的不咋滴，凑合着看吧，画圆弧主要用的贝塞尔曲线画的，我感觉这个比较简单，当然大家也可以使用圆的方程，抛物线的方程都可以实现这种效果

但是我比较倾向于用贝塞尔，如果大家会ps的话，知道里边有一个钢笔工具，他就是贝塞尔的原理，贝塞尔的算法大家可以去网上搜搜，

贝塞尔计算方法类网上也有很多

下面先上我的代码

using UnityEngine;

[System.Serializable]

public class Bezier : System.Object

{

public Vector3 p0;

public Vector3 p1;

public Vector3 p2;

public Vector3 p3;

public float ti = 0f;

private Vector3 b0 = Vector3.zero;

private Vector3 b1 = Vector3.zero;

private Vector3 b2 = Vector3.zero;

private Vector3 b3 = Vector3.zero;

private float Ax;

private float Ay;

private float Az;

private float Bx;

private float By;

private float Bz;

private float Cx;

private float Cy;

private float Cz;

public Bezier( Vector3 v0, Vector3 v1, Vector3 v2, Vector3 v3 )

{

this.p0 = v0;

this.p1 = v1;

this.p2 = v2;

this.p3 = v3;

}

// 0.0 >= t <= 1.0

public Vector3 GetPointAtTime( float t )

{

this.CheckConstant();

float t2 = t * t;

float t3 = t * t * t;

float x = this.Ax * t3 + this.Bx * t2 + this.Cx * t + p0.x;

float y = this.Ay * t3 + this.By * t2 + this.Cy * t + p0.y;

float z = this.Az * t3 + this.Bz * t2 + this.Cz * t + p0.z;

return new Vector3( x, y, z );

}

private void SetConstant()

{

this.Cx = 3f * ( ( this.p0.x + this.p1.x ) - this.p0.x );

this.Bx = 3f * ( ( this.p3.x + this.p2.x ) - ( this.p0.x + this.p1.x ) ) - this.Cx;

this.Ax = this.p3.x - this.p0.x - this.Cx - this.Bx;

this.Cy = 3f * ( ( this.p0.y + this.p1.y ) - this.p0.y );

this.By = 3f * ( ( this.p3.y + this.p2.y ) - ( this.p0.y + this.p1.y ) ) - this.Cy;

this.Ay = this.p3.y - this.p0.y - this.Cy - this.By;

this.Cz = 3f * ( ( this.p0.z + this.p1.z ) - this.p0.z );

this.Bz = 3f * ( ( this.p3.z + this.p2.z ) - ( this.p0.z + this.p1.z ) ) - this.Cz;

this.Az = this.p3.z - this.p0.z - this.Cz - this.Bz;

}

// Check if p0, p1, p2 or p3 have changed

private void CheckConstant()

{

if( this.p0 != this.b0 || this.p1 != this.b1 || this.p2 != this.b2 || this.p3 != this.b3 )

{

this.SetConstant();

this.b0 = this.p0;

this.b1 = this.p1;

this.b2 = this.p2;

this.b3 = this.p3;

}

}

}

这就是贝塞尔计算类，很简单的计算方法，

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class TriangleSubdivision  :MonoBehaviour{
public static int[] TriangulatePolygon (Vector2[] XZofVertices) {
//
int VertexCount = XZofVertices.Length;
//minx miny  maxx maxy
float xmin = XZofVertices[0].x;
float ymin = XZofVertices[0].y;
float xmax = xmin;
float ymax = ymin;
for (int ii1 = 1; ii1 < VertexCount; ii1++)
{
if (XZofVertices[ii1].x < xmin)
{
xmin = XZofVertices[ii1].x;
}
else if (XZofVertices[ii1].x > xmax)
{
xmax = XZofVertices[ii1].x;
}
if (XZofVertices[ii1].y < ymin)
{
ymin = XZofVertices[ii1].y;
}
else if (XZofVertices[ii1].y > ymax)
{
ymax = XZofVertices[ii1].y;
}
}
float dx = xmax - xmin;
float dy = ymax - ymin;
float dmax = (dx > dy) ? dx : dy;
float xmid = (xmax + xmin) * 0.5f;
float ymid = (ymax + ymin) * 0.5f;
Vector2[] ExpandedXZ = new Vector2[3 + VertexCount];
for (int ii1 = 0; ii1 < VertexCount; ii1++)
{
ExpandedXZ[ii1] = XZofVertices[ii1];
}
ExpandedXZ[VertexCount] = new Vector2((xmid - 2 * dmax), (ymid - dmax));
ExpandedXZ[VertexCount + 1] = new Vector2(xmid, (ymid + 2 * dmax));
ExpandedXZ[VertexCount + 2] = new Vector2((xmid + 2 * dmax), (ymid - dmax));
List<Triangle> TriangleList = new List<Triangle>();
TriangleList.Add(new Triangle(VertexCount, VertexCount+1, VertexCount+2));
for (int ii1 = 0; ii1 < VertexCount; ii1++)
{
//检查构成的三角形
List<Edge> Edges = new List<Edge>();
for (int ii2 = 0; ii2 < TriangleList.Count; ii2++)
{
if (TriangulatePolygonSubFunc_InCircle(ExpandedXZ[ii1], ExpandedXZ[TriangleList[ii2].p1],ExpandedXZ[TriangleList[ii2].p2],ExpandedXZ[TriangleList[ii2].p3]))
{
Edges.Add(new Edge(TriangleList[ii2].p1, TriangleList[ii2].p2));
Edges.Add(new Edge(TriangleList[ii2].p2, TriangleList[ii2].p3));
Edges.Add(new Edge(TriangleList[ii2].p3, TriangleList[ii2].p1));
TriangleList.RemoveAt(ii2);
ii2--;
}
}
if (ii1 >= VertexCount) { continue; }
//判断相同的三个点构成的三角形
for (int ii2 = Edges.Count - 2; ii2 >= 0; ii2--)
{
for (int ii3 = Edges.Count - 1; ii3 >= ii2 + 1; ii3--)
{
if (Edges[ii2].Equals(Edges[ii3]))
{
Edges.RemoveAt(ii3);
Edges.RemoveAt(ii2);
ii3--;
continue;
}
}
}
for (int ii2 = 0; ii2 < Edges.Count; ii2++)
{
TriangleList.Add(new Triangle(Edges[ii2].p1, Edges[ii2].p2, ii1));
}
Edges.Clear();
Edges = null;
}
//大于点集外围的点
for (int ii1 = TriangleList.Count - 1; ii1 >= 0; ii1--)
{
if (TriangleList[ii1].p1 >= VertexCount ||TriangleList[ii1].p2 >= VertexCount ||TriangleList[ii1].p3 >= VertexCount)
{
TriangleList.RemoveAt(ii1);
}
}
//不在房间内的面
for(int ii3 = 0;ii3<TriangleList.Count;ii3++){
if(TriangleInPolygonOuter(XZofVertices,XZofVertices[TriangleList[ii3].p1],XZofVertices[TriangleList[ii3].p2],XZofVertices[TriangleList[ii3].p3])){
TriangleList.RemoveAt(ii3);
ii3--;
}
}
TriangleList.TrimExcess();
int[] Triangles = new int[3 * TriangleList.Count];
for (int ii1 = 0; ii1 < TriangleList.Count; ii1++)
{
Triangles[3 * ii1] = TriangleList[ii1].p1;
Triangles[3 * ii1 + 1] = TriangleList[ii1].p2;
Triangles[3 * ii1 + 2] = TriangleList[ii1].p3;
}
return Triangles;
}
static bool TriangulatePolygonSubFunc_InCircle(Vector2 p, Vector2 p1, Vector2 p2, Vector2 p3) {
if (Mathf.Abs(p1.y - p2.y) < 0.0000001&&Mathf.Abs(p2.y - p3.y) < 0.0000001)
{
return false;
}
float m1, m2, mx1, mx2, my1, my2, xc, yc;
if (Mathf.Abs(p2.y - p1.y) < 0.0000001)
{
m2 = -(p3.x - p2.x) / (p3.y - p2.y);
mx2 = (p2.x + p3.x) * 0.5f;
my2 = (p2.y + p3.y) * 0.5f;
xc = (p2.x + p1.x) * 0.5f;
yc = m2 * (xc - mx2) + my2;
}
else if (Mathf.Abs(p3.y - p2.y) < 0.0000001)
{
m1 = -(p2.x - p1.x) / (p2.y - p1.y);
mx1 = (p1.x + p2.x) * 0.5f;
my1 = (p1.y + p2.y) * 0.5f;
xc = (p3.x + p2.x) * 0.5f;
yc = m1 * (xc - mx1) + my1;
}
else
{
m1 = -(p2.x - p1.x) / (p2.y - p1.y);
m2 = -(p3.x - p2.x) / (p3.y - p2.y);
mx1 = (p1.x + p2.x) * 0.5f;
mx2 = (p2.x + p3.x) * 0.5f;
my1 = (p1.y + p2.y) * 0.5f;
my2 = (p2.y + p3.y) * 0.5f;
xc = (m1 * mx1 - m2 * mx2 + my2 - my1) / (m1 - m2);
yc = m1 * (xc - mx1) + my1;
}
float dx = p2.x - xc;
float dy = p2.y - yc;
float rsqr = dx * dx + dy * dy;
dx = p.x - xc;
dy = p.y - yc;
double drsqr = dx * dx + dy * dy;
return (drsqr <= rsqr);
}
static bool TriangleInPolygonOuter(Vector2[] pList,Vector2 p1,Vector2 p2,Vector2 p3){
Vector2[] centerPoint = new Vector2[3];
centerPoint[0] = new Vector2((p1.x+p2.x)/2,(p1.y+p2.y)/2);
centerPoint[1] = new Vector2((p1.x+p3.x)/2,(p1.y+p3.y)/2);
centerPoint[2] = new Vector2((p3.x+p2.x)/2,(p3.y+p2.y)/2);
for(int j = 0,crossNum = 0;j<centerPoint.Length;j++){
for (int i = 0; i < pList.Length; i++)
{
if (IsPointInLine(centerPoint[j].x, centerPoint[j].y, pList[i].x, pList[i].y, pList[(i+1)%pList.Length].x, pList[(i+1)%pList.Length].y)==0)
{
crossNum=crossNum+1;
continue;
}else if(IsPointInLine(centerPoint[j].x, centerPoint[j].y, pList[i].x, pList[i].y, pList[(i+1)%pList.Length].x, pList[(i+1)%pList.Length].y)==2){
crossNum = 1;
break;
}
}
if ((crossNum % 2) == 0)
{
return true;
}
crossNum = 0;
}

return false;
}
//0   在外  1  在内   2  边上
static int IsPointInLine(float x,float y,float x1,float y1,float x2,float y2)
{
float maxY =y1;
float minY = y2;
if(y1>y2){
maxY = y1;
minY = y2;
}else{
maxY = y2;
minY = y1;
}
float averageX = (x1+x2)/2;
float averageY = (y1+y2)/2;
if(y==averageY&&x==averageX){
return 2;
}
if (y < maxY && y >minY)
{
if (x >(x1 + (x2 - x1) * (y - y1) / (y2 - y1)))
{
return 0;
}
}
return 1;
}
}
struct Triangle
{
public int p1;
public int p2;
public int p3;
public Triangle(int point1, int point2, int point3)
{
p1 = point1; p2 = point2; p3 = point3;
}
}
class Edge
{
public int p1;
public int p2;
public Edge(int point1, int point2)
{
p1 = point1; p2 = point2;
}
public Edge() : this(0, 0)
{}
public bool Equals(Edge other)
{
return ((this.p1 == other.p2) && (this.p2 == other.p1)) ||((this.p1 == other.p1) && (this.p2 == other.p2));
}
}

这个类上一张已经说过了，就是画不规则图形的类，不过我这篇文章是把圆和不规则拼接出带有圆弧状的图形，看图大家就会明白了

using UnityEngine;
using System.Collections;

public class ChartletManager : System.Object {
Bezier myBezier;
public ChartletManager(){

}
public GameObject WallChartletInMesh(GameObject obj,Vector3 startPoint,Vector3 endPoint,float height,Texture2D tex,float excursion,float zoom)
{
myBezier = new Bezier( startPoint,  new Vector3( excursion, zoom, 0f ),  new Vector3( excursion, zoom, 0f ), endPoint);
MeshFilter	myFilter = (MeshFilter)obj.GetComponent (typeof(MeshFilter));
Mesh myMesh = myFilter.mesh;
Vector3[] myVertices = new Vector3[52];
for(int i = 0;i<52;i++){
if(i<26){
myVertices[i] = myBezier.GetPointAtTime( (float)((i) *0.04) );
myVertices[i] = new Vector3(myVertices[i].x,myVertices[i].y,myVertices[i].z-height);
}else{
myVertices[i] = myBezier.GetPointAtTime( (float)((i-26) *0.04) );
myVertices[i] = new Vector3(myVertices[i].x,myVertices[i].y,myVertices[i].z);
}
}
myMesh.vertices = myVertices;
int[] myTriangles = new int[52 * 3];
for(int i = 0; i < 52; i++){
if(i<25){
myTriangles[i*3] = 26+i;
myTriangles[i*3+1] = i;
myTriangles[i*3+2] = i+1;
}else if(i == 25||i==51){
myTriangles[i*3] = 0;
myTriangles[i*3+1] = 0;
myTriangles[i*3+2] = 0;
}else{
myTriangles[i*3+2] = i;
myTriangles[i*3+1] = i+1;
myTriangles[i*3] = i-25;
}
}
Vector2[] myuvs = new Vector2[52];
for (int i = 0; i < 52; i++) {
myuvs [i] = new Vector2 ( (myVertices [i].x),  (myVertices [i].y));
}
myMesh.triangles = myTriangles;
myMesh.uv = myuvs;
myMesh.RecalculateBounds ();
myMesh.RecalculateNormals ();
obj.renderer.material.mainTexture = tex;
return obj;
}
public GameObject CircleChartletInMesh(GameObject obj,Vector3 startPoint,Vector3 endPoint,Texture2D tex,float excursion,float zoom)
{
myBezier = new Bezier( startPoint,  new Vector3( excursion, zoom, 0f ),  new Vector3( excursion, zoom, 0f ), endPoint);
MeshFilter	myFilter = (MeshFilter)obj.GetComponent (typeof(MeshFilter));
Mesh myMesh = myFilter.mesh;

Vector3[] myVertices = new Vector3[27];
myVertices[0] = new Vector3(0,0,0);
for(int i =0; i <= 25; i++)
{
myVertices[i+1]  = myBezier.GetPointAtTime( (float)(i *0.04) );
}

myMesh.vertices = myVertices;

Vector2[] myuvs = new Vector2[27];
for (int i = 0; i < 27; i++) {
myuvs [i] = new Vector2 ( (myVertices [i].x),  (myVertices [i].y));
}
myMesh.triangles = TriangleSubdivision.TriangulatePolygon(myuvs);
myMesh.uv = myuvs;
myMesh.RecalculateBounds ();
myMesh.RecalculateNormals ();
obj.renderer.material.mainTexture = tex;
return obj;
}
public GameObject CircleAndTriangleChartletInMesh(GameObject obj,Vector3 startPoint,Vector3 endPoint,Vector3[] points,Texture2D tex,float excursion,float zoom)
{
myBezier = new Bezier( startPoint,  new Vector3( excursion, zoom, 0f ),  new Vector3( excursion, zoom, 0f ), endPoint);
MeshFilter	myFilter = (MeshFilter)obj.GetComponent (typeof(MeshFilter));
Mesh myMesh = myFilter.mesh;
Vector3[] myVertices = new Vector3[27+points.Length];

myVertices[0] = new Vector3((startPoint.x+endPoint.x)/2,(startPoint.y+endPoint.y)/2,(startPoint.z+endPoint.z)/2);
for(int i =0; i <= 25; i++)
{
myVertices[i+1]  = myBezier.GetPointAtTime( (float)(i *0.04) );
}
for(int i = 27;i<27+points.Length;i++){
myVertices[i] = points[i-27];
}
myMesh.vertices = myVertices;
Vector2[] myuvs = new Vector2[27+points.Length];
for (int i = 0; i < myuvs.Length; i++) {
myuvs [i] = new Vector2 ( (myVertices [i].x),  (myVertices [i].y));
}
myMesh.triangles = TriangleSubdivision.TriangulatePolygon(myuvs);
myMesh.uv = myuvs;

myMesh.RecalculateBounds ();
myMesh.RecalculateNormals ();
obj.renderer.material.mainTexture = tex;
return obj;
}
}

为了方便大家测试，我把我的测试放在了一个类里，大家直接调这个方法即可，我是测试用的，大家可以修改成自己的脚本

using UnityEngine;

public class MyBezier : MonoBehaviour

{
public Bezier myBezier;
public GameObject circleline;
public Texture2D tex;
void Start()
{

GameObject floorTexture = (GameObject)Instantiate(circleline,new Vector3(0,0,10),Quaternion.Euler(new Vector3(0,0,0)));
GameObject wallTexture =(GameObject) Instantiate(circleline,new Vector3(0,0,10),Quaternion.Euler(new Vector3(0,0,0)));
ChartletManager chartlet = new ChartletManager();
Vector3[] ceilVertices = new Vector3[4];
ceilVertices[0] = new Vector3(-4,0,0);
ceilVertices[1] = new Vector3(-4,-5,0);
ceilVertices[2] = new Vector3(4,-5,0);
ceilVertices[3] = new Vector3(4,0,0);
//		ceilVertices[1] = new Vector3(-5,1,0);
//		ceilVertices[2] = new Vector3(-5,-4,0);
//		ceilVertices[3] = new Vector3(-2,-4.5f,0);
//		ceilVertices[4] = new Vector3(-2.5f,-2,0);
//		ceilVertices[5] = new Vector3(2,-2.5f,0);
//		ceilVertices[6] = new Vector3(2.5f,-4,0);
//		ceilVertices[7] = new Vector3(5,-4,0);
//		ceilVertices[8] = new Vector3(5,0,0);
//		ceilVertices[9] = new Vector3(4,0,0);

wallTexture= chartlet.WallChartletInMesh(wallTexture,new Vector3( -4f, 0f, 0f ),new Vector3( 4f, 0f, 0f ),3.0f,tex,0,6);
floorTexture= chartlet.CircleAndTriangleChartletInMesh(floorTexture,new Vector3( -4f, 0f, 0f ),new Vector3( 4f, 0f, 0f ),ceilVertices,tex,0,6);
}

}

测试用例，大家可以做自己想要的东西了，CircleAndTriangleChartletInMesh(GameObject obj,Vector3 startPoint,Vector3 endPoint,Vector3[] points

,Texture2D tex,float excursion,float zoom)

我解释一下这个类的传递参数吧

obj,就是传进来的obj对象，大家可以使用out，那个直接能用了

startPoint圆弧起始点

endPoint终点圆弧点

points 是传入的不规则图形的各个点

tex 是那张贴图

excursion这个是圆弧的 倾斜度

zoom是圆弧的大小就是圆弧顶点到起始点于终止点中间的那个点的距离   正规半圆这个值应该是圆半径的1.5倍

using UnityEngine;

public class MyBezier : MonoBehaviour

{
public Bezier myBezier;
public GameObject circleline;
public Texture2D tex;
void Start()
{

GameObject floorTexture = (GameObject)Instantiate(circleline,new Vector3(0,0,10),Quaternion.Euler(new Vector3(0,0,0)));
GameObject wallTexture =(GameObject) Instantiate(circleline,new Vector3(0,0,10),Quaternion.Euler(new Vector3(0,0,0)));
ChartletManager chartlet = new ChartletManager();
Vector3[] ceilVertices = new Vector3[10];
ceilVertices[0] = new Vector3(-4,0,0);
//		ceilVertices[1] = new Vector3(-4,-5,0);
//		ceilVertices[2] = new Vector3(4,-5,0);
//		ceilVertices[3] = new Vector3(4,0,0);
ceilVertices[1] = new Vector3(-5,1,0);
ceilVertices[2] = new Vector3(-5,-4,0);
ceilVertices[3] = new Vector3(-2,-4.5f,0);
ceilVertices[4] = new Vector3(-2.5f,-2,0);
ceilVertices[5] = new Vector3(2,-2.5f,0);
ceilVertices[6] = new Vector3(2.5f,-4,0);
ceilVertices[7] = new Vector3(5,-4,0);
ceilVertices[8] = new Vector3(5,0,0);
ceilVertices[9] = new Vector3(4,0,0);

wallTexture= chartlet.WallChartletInMesh(wallTexture,new Vector3( -4f, 0f, 0f ),new Vector3( 4f, 0f, 0f ),3.0f,tex,3,8);
floorTexture= chartlet.CircleAndTriangleChartletInMesh(floorTexture,new Vector3( -4f, 0f, 0f ),new Vector3( 4f, 0f, 0f ),ceilVertices,tex,3,8);
}

}

如果我数值改改就会出现这种，zoom就是倾斜程度，当然也可以是负数，是往里凹进去的，excursion是负数就向另一个方向倾斜。

凹进去的就是这种情况，具体情况大家可以测试，值的范围有限制的，超出了，会出现空的情况，当然我写的也有很多不足之处，大家可以修改修改

不知为何 csdn编辑问题，我的图片文字与代码都混合了 所以乱了 我把我的工程打包上去 大家可以下载看看具体实现效果

下载地址

http://download.csdn.net/detail/pzw0416/6727303