pcl画二维圆

已知圆的坐标（x,y）,和半径，画圆，以下代码为画半径不同的同心圆，其中需要确定二维点云的法向量，可以自己设置，也可根据已有的平面点云的法向量设置，本代码为平面已有的点云法向量

// 构造三维圆点云,cloud为生成的点云，R为圆的半径
bool Imgdeal::Generate3DCircle(pcl_ptr &circle3DCloud, pcl::PointXYZ &circleCenter, pcl_nml &cloud_normals, double R)
{
    Eigen::Vector3f c = circleCenter.getVector3fMap();
    float cx = c[0], cy = c[1], cz = c[2];                        // 圆-中心
    float r = R;                                                  // 圆-半径

    Eigen::Vector3f i(1.0, 0.0, 0.0);
    Eigen::Vector3f j(0.0, 1.0, 0.0);
    Eigen::Vector3f k(0.0, 0.0, 1.0);

    double nm_x = cloud_normals->points[0].normal_x;
    double nm_y = cloud_normals->points[0].normal_y;
    double nm_z = cloud_normals->points[0].normal_z;

    Eigen::Vector3f n(nm_x, nm_y, nm_z);   // 圆-法向量
 
    Eigen::Vector3f a(0.0, 0.0, 0.0);
    Eigen::Vector3f b(0.0, 0.0, 0.0);
    // 求向量a
    a = n.cross(i);
    if(a.norm() == 0.0)
    {
        a = n.cross(j);
    }

    if(a.norm() == 0.0)
    {
        a = n.cross(k);
    }
    // 求向量 b
    b = n.cross(a);
    // 归一化a，b（圆面两个互垂直向量）
    a.normalize();
    b.normalize();
    //利用空间圆的参数方程生成圆

    float xi, yi, zi;
    float x1i, y1i, z1i;
    float x2i, y2i, z2i;
    float x3i, y3i, z3i;
    float x4i, y4i, z4i;
    float x5i, y5i, z5i;
    float x6i, y6i, z6i;
    float x7i, y7i, z7i;
    float x8i, y8i, z8i;

    float t = -180.0;
    float angle = pcl::deg2rad(t);
    std::vector<float> x, y, z;

    while (-180.0 <= t & t <= 180.0)
    {
        xi = cx + r*(a[0]*cos(angle) + b[0]*sin(angle));
        yi = cy + r*(a[1]*cos(angle) + b[1]*sin(angle));
        zi = cz + r*(a[2]*cos(angle) + b[2]*sin(angle));

        x1i = cx + r/1.5*(a[0]*cos(angle) + b[0]*sin(angle));
        y1i = cy + r/1.5*(a[1]*cos(angle) + b[1]*sin(angle));
        z1i = cz + r/1.5*(a[2]*cos(angle) + b[2]*sin(angle));

        x2i = cx + r/2*(a[0]*cos(angle) + b[0]*sin(angle));
        y2i = cy + r/2*(a[1]*cos(angle) + b[1]*sin(angle));
        z2i = cz + r/2*(a[2]*cos(angle) + b[2]*sin(angle));

        x3i = cx + r/2.5*(a[0]*cos(angle) + b[0]*sin(angle));
        y3i = cy + r/2.5*(a[1]*cos(angle) + b[1]*sin(angle));
        z3i = cz + r/2.5*(a[2]*cos(angle) + b[2]*sin(angle));

        x4i = cx + r/3*(a[0]*cos(angle) + b[0]*sin(angle));
        y4i = cy + r/3*(a[1]*cos(angle) + b[1]*sin(angle));
        z4i = cz + r/3*(a[2]*cos(angle) + b[2]*sin(angle));

        x5i = cx + r/4*(a[0]*cos(angle) + b[0]*sin(angle));
        y5i = cy + r/4*(a[1]*cos(angle) + b[1]*sin(angle));
        z5i = cz + r/4*(a[2]*cos(angle) + b[2]*sin(angle));

        x6i = cx + r/5*(a[0]*cos(angle) + b[0]*sin(angle));
        y6i = cy + r/5*(a[1]*cos(angle) + b[1]*sin(angle));
        z6i = cz + r/5*(a[2]*cos(angle) + b[2]*sin(angle));

        x7i = cx + r/6*(a[0]*cos(angle) + b[0]*sin(angle));
        y7i = cy + r/6*(a[1]*cos(angle) + b[1]*sin(angle));
        z7i = cz + r/6*(a[2]*cos(angle) + b[2]*sin(angle));

        x8i = cx + r/7*(a[0]*cos(angle) + b[0]*sin(angle));
        y8i = cy + r/7*(a[1]*cos(angle) + b[1]*sin(angle));
        z8i = cz + r/7*(a[2]*cos(angle) + b[2]*sin(angle));

        x.push_back(xi);
        y.push_back(yi);
        z.push_back(zi);

        x.push_back(x1i);
        y.push_back(y1i);
        z.push_back(z1i);

        x.push_back(x2i);
        y.push_back(y2i);
        z.push_back(z2i);

        x.push_back(x3i);
        y.push_back(y3i);
        z.push_back(z3i);

        x.push_back(x4i);
        y.push_back(y4i);
        z.push_back(z4i);

        x.push_back(x5i);
        y.push_back(y5i);
        z.push_back(z5i);

        x.push_back(x6i);
        y.push_back(y6i);
        z.push_back(z6i);

        x.push_back(x7i);
        y.push_back(y7i);
        z.push_back(z7i);

        x.push_back(x8i);
        y.push_back(y8i);
        z.push_back(z8i);

        t = t + 1;
        angle = pcl::deg2rad(t);
    }

    // for(int i=1; i++; i<8)
    // {
    //     while (-180.0 <= t & t <= 180.0)
    //     {
    //         xi = cx + (r/i)*(a[0]*cos(angle) + b[0]*sin(angle));
    //         yi = cy + (r/i)*(a[1]*cos(angle) + b[1]*sin(angle));
    //         zi = cz + (r/i)*(a[2]*cos(angle) + b[2]*sin(angle));

    //         x.push_back(xi);
    //         y.push_back(yi);
    //         z.push_back(zi);

    //         t = t + 1;
    //         angle = pcl::deg2rad(t);
    //     }
    // }                                           //算法时间慢
   
    //定义cloudPoints大小,无序点云
    circle3DCloud->resize(x.size());
    for (int i = 0; i < x.size(); i++){
        //将三维坐标赋值给PCL点云坐标
        (*circle3DCloud)[i].x = x[i];
        (*circle3DCloud)[i].y = y[i];
        (*circle3DCloud)[i].z = z[i];
    }
    // writer.write("../PointsCloud/circle3DCloud.pcd", *circle3DCloud);

    return true;
}

使用方法为：

 pcl::PointXYZ lylord_Center{(float)x, (float)y, 2.0};
 Generate3DCircle(generate_cloud, lylord_Center, cloud_normals, lylord_devlate/(2+number));

自己设置的方法为：
 

pcl::Normal N{0.5,0.5,1.0};
PCL::PointXYZ center{0.0,0.0,0.0};