绝了！你裁我剪，斯尼帕！文末源码

/** 计算uv, 锚点都是中心 */public static computeUv(points: cc.Vec2[], width: number, height: number) {    let uvs: cc.Vec2[] = [];    for(const p of points) {        let x = MathUtils.clamp(0, 1, (p.x + width/2) / width);        let y = MathUtils.clamp(0, 1, 1. - (p.y + height/2) / height);        uvs.push(cc.v2(x, y));    }    return uvs;}

/** 更新uv */protected updateUVs(comp: TexturePlus) {    let uvOffset = this.uvOffset;    let floatsPerVert = this.floatsPerVert;    let verts = this._renderData.vDatas[0];    let uvs = [];    if(comp.texture) {        uvs = CommonUtils.computeUv(comp.polygon, comp.texture.width, comp.texture.height)    }    let polygon = comp.polygon;    for(let i=0; i        let dstOffset = floatsPerVert * i + uvOffset;        verts[dstOffset] = uvs[i].x;        verts[dstOffset + 1] = uvs[i].y;    }}

/** 填充顶点的color */public updateColor(comp: TexturePlus, color: number) {    let uintVerts = this._renderData.uintVDatas[0];    if(!uintVerts) return ;    color = color != null ? color : comp.node.color['_val'];    let floatsPerVert = this.floatsPerVert;    let colorOffset = this.colorOffset;
    let polygon = comp.polygon;    for(let i=0; i        uintVerts[colorOffset + i * floatsPerVert] = color;    }        }

/** render-data.js */updateMesh (index, vertices, indices) {    this.vDatas[index] = vertices;
    // 将vertices.buffer当成参数传入, 他们共享同一段buffer    this.uintVDatas[index] = new Uint32Array(vertices.buffer, 0, vertices.length);    this.iDatas[index] = indices;
    this.meshCount = this.vDatas.length;},
createData (index, verticesFloats, indicesCount) {    let vertices = new Float32Array(verticesFloats);    let indices = new Uint16Array(indicesCount);    this.updateMesh(index, vertices, indices);},

// 将多边形分解为多个三角形public static splitPolygonByTriangle(points: cc.Vec2[]): number[] {    if(points.length <= 3) return [0, 1, 2];    let pointMap: {[key: string]: number} = {};     // point与idx的映射    for(let i=0; i        let p = points[i];        pointMap[`${p.x}-${p.y}`] = i;    }    const getIdx = (p: cc.Vec2) => {        return pointMap[`${p.x}-${p.y}`]    }    points = points.concat([]);    let idxs: number[] = [];
    let index = 0;    while(points.length > 3) {        let p1 = points[(index) % points.length]        , p2 = points[(index+1) % points.length]        , p3 = points[(index+2) % points.length];        let splitPoint = (index+1) % points.length;
        let v1 = p2.sub(p1);        let v2 = p3.sub(p2);        if(v1.cross(v2) < 0) {      // 是一个凹角, 寻找下一个            index = (index + 1) % points.length;            continue;        }        let hasPoint = false;        for(const p of points) {            if(p != p1 && p != p2 && p != p3 && this.isInTriangle(p, p1, p2 ,p3)) {                hasPoint = true;                break;            }        }        if(hasPoint) {      // 当前三角形包含其他点, 寻找下一个            index = (index + 1) % points.length;            continue;        }        // 找到了耳朵, 切掉        idxs.push(getIdx(p1), getIdx(p2), getIdx(p3));        points.splice(splitPoint, 1);    }    for(const p of points) {        idxs.push(getIdx(p));    }    return idxs;}

// 判断一个点是否在三角形内public static isInTriangle(point: cc.Vec2, triA: cc.Vec2, triB: cc.Vec2, triC: cc.Vec2) {    let AB = triB.sub(triA), AC = triC.sub(triA), BC = triC.sub(triB), AD = point.sub(triA), BD = point.sub(triB);    //@ts-ignore    return (AB.cross(AC) >= 0 ^ AB.cross(AD) < 0)  && (AB.cross(AC) >= 0 ^ AC.cross(AD) >= 0) && (BC.cross(AB) > 0 ^ BC.cross(BD) >= 0);}

this.indicesArr = CommonUtils.splitPolygonByTriangle(comp.polygon);

/** 更新顶点数据 */protected updateVerts(comp: TexturePlus) {    this.indicesArr = CommonUtils.splitPolygonByTriangle(comp.polygon);    this.updateWorldVerts(comp);}
/** 更新renderdata */protected updateRenderData(comp: TexturePlus) {    if (comp._vertsDirty) {        this.resetData(comp);        this.updateUVs(comp);        this.updateVerts(comp);        this.updateColor(comp, null);        comp._vertsDirty = false;    }}

public initData() {    let data = this._renderData;    data.createQuadData(0, this.verticesFloats, this.indicesCount);}
public resetData(comp: TexturePlus) {    let points = comp.polygon;    if(!points || points.length < 3) return ;    this.verticesCount = points.length;    this.indicesCount = this.verticesCount + (this.verticesCount - 3) * 2;    this._renderData.clear();    this.initData();}

//每帧都会被调用fillBuffers(comp: TexturePlus, renderer) {    if (renderer.worldMatDirty) {        this.updateWorldVerts(comp);    }
    let renderData = this._renderData;
    // vData里包含 pos, uv, color数据, iData中包含三角形顶点索引    let vData = renderData.vDatas[0];    let iData = renderData.iDatas[0];
    let buffer = this.getBuffer();    let offsetInfo = buffer.request(this.verticesCount, this.indicesCount);
    // buffer data may be realloc, need get reference after request.
    // fill vertices    let vertexOffset = offsetInfo.byteOffset >> 2,        vbuf = buffer._vData;    if (vData.length + vertexOffset > vbuf.length) {        vbuf.set(vData.subarray(0, vbuf.length - vertexOffset), vertexOffset);    } else {        vbuf.set(vData, vertexOffset);    }
    // fill indices    let ibuf = buffer._iData,        indiceOffset = offsetInfo.indiceOffset,        // vertexId是已经在buffer里的顶点数,也是当前顶点序号的基数        vertexId = offsetInfo.vertexOffset;             
    let ins = this.indicesArr;    for(let i=0; i        ibuf[indiceOffset++] = vertexId + ins[i];    }}