#include <iostream>
#include <boost/format.hpp>
#include <QtGui>
#include <CGAL/Qt/GraphicsViewNavigation.h>
#include <QLineF>
#include <QRectF>
#include <QApplication>
#include <QGraphicsScene>
#include <QGraphicsView>
int main(int argc, char **argv)
{
    QApplication app(argc, argv);
    QGraphicsScene scene;
    scene.setSceneRect(0,0, 100, 100);
    scene.addRect(QRectF(0,0, 150, 100));
    scene.addLine(QLineF(0,0, 100, 100));
    scene.addLine(QLineF(0,100, 100, 0));
    QGraphicsView* view = new QGraphicsView(&scene);
    CGAL::Qt::GraphicsViewNavigation navigation;
    view->installEventFilter(&navigation);
    view->viewport()->installEventFilter(&navigation);
    view->setRenderHint(QPainter::Antialiasing);
    view->show();
    return app.exec();
}

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Delaunay_triangulation_on_sphere_traits_2.h>
#include <CGAL/Projection_on_sphere_traits_3.h>
#include <CGAL/Delaunay_triangulation_on_sphere_2.h>
#include <CGAL/point_generators_3.h>
#include <CGAL/utility.h>
#include <CGAL/Qt/DemosMainWindow.h>
#include <QApplication>
#include <QMainWindow>
#include <QFileDialog>
#include <QInputDialog>
#include <CGAL/Three/Three.h>
#include <boost/iterator/transform_iterator.hpp>
typedef CGAL::Exact_predicates_inexact_constructions_kernel             Kernel;
typedef Kernel::FT                                                      FT;
typedef Kernel::Point_3                                                 Point_3;
typedef std::vector<Point_3>                                            PointList;
typedef CGAL::Creator_uniform_3<double, Point_3>                        Points_Creator;
typedef CGAL::Projection_on_sphere_traits_3<Kernel>                     Projection_on_sphere;
typedef CGAL::Delaunay_triangulation_on_sphere_2<Projection_on_sphere>  Delauney_on_sphere;
typedef std::list<std::vector<Point_3> >                                Subsampled_arcs;
#include "Viewer.h"
#include "ui_Mainwindow.h"
class MainWindow
  : public CGAL::Qt::DemosMainWindow,
    public Ui::MainWindow
{
  Q_OBJECT
public:
  MainWindow()
  {
    setupUi(this);
  }
public slots:
  void on_action_Quit_triggered()
  {
    close();
  }
  void on_action_New_triggered()
  {
    PointList points;
    CGAL::points_on_cube_grid_3( 1.0, 20000, std::back_inserter(points), Points_Creator() );
    Projection_on_sphere sphere( Point_3(0.0, 0.0, 0.0), 100.0 );
    Delauney_on_sphere triangulation( points.begin(), points.end(), sphere );
    // Instantiate the viewer
    viewer->open( points.begin(), points.end(), triangulation );
  }
};
int main(int argc, char** argv)
{
  // Read command lines arguments
  QApplication application(argc,argv);
  MainWindow mainWindow;
  mainWindow.show();
  // Run main loop
  return application.exec();
}
#include "main.moc"

#ifndef POLYHEDRON_DEMO_CREATE_SPHERE_H
#define POLYHEDRON_DEMO_CREATE_SPHERE_H
#include <CGAL/number_type_config.h>
#include <cmath>
#include <vector>
template <class FLOAT>
void create_flat_sphere(FLOAT R,
                        std::vector<FLOAT>& positions_spheres,
                        std::vector<FLOAT>& normals_spheres,
                        int prec = 36)
{
  // The smaller they are, the more precise the sphere will be
  // Must be divisors of 180 and 360
  const float rings = float(prec) / 2;
  const float sectors = float(prec);
  const float to_rad = static_cast<float>(CGAL_PI / 180.);
  float T, P;
  float x[4],y[4],z[4];
  //Top of the sphere
  for(float t=0; t<360.f; t+=sectors)
  {
    positions_spheres.push_back(0);
    positions_spheres.push_back(0);
    positions_spheres.push_back(R);
    normals_spheres.push_back(0);
    normals_spheres.push_back(0);
    normals_spheres.push_back(1);
    P = rings*to_rad;
    T = t*to_rad;
    x[1] = sin(P) * cos(T);
    y[1] = sin(P) * sin(T);
    z[1] = cos(P);
    positions_spheres.push_back(R * x[1]);
    positions_spheres.push_back(R * y[1]);
    positions_spheres.push_back(R * z[1]);
    normals_spheres.push_back(x[1]);
    normals_spheres.push_back(y[1]);
    normals_spheres.push_back(z[1]);
    //
    P = rings*to_rad;
    T = (t+sectors)*to_rad;
    x[2] = sin(P) * cos(T);
    y[2] = sin(P) * sin(T);
    z[2] = cos(P);
    positions_spheres.push_back(R * x[2]);
    positions_spheres.push_back(R * y[2]);
    positions_spheres.push_back(R * z[2]);
    normals_spheres.push_back(x[2]);
    normals_spheres.push_back(y[2]);
    normals_spheres.push_back(z[2]);
  }
  //Body of the sphere
  for(float p=rings; p<180.f-rings; p+=rings)
  {
    for(float t=0; t<360.f; t+=sectors)
    {
      //A
      P = p*to_rad;
      T = t*to_rad;
      x[0] = sin(P) * cos(T);
      y[0] = sin(P) * sin(T);
      z[0] = cos(P);
      positions_spheres.push_back(R * x[0]);
      positions_spheres.push_back(R * y[0]);
      positions_spheres.push_back(R * z[0]);
      normals_spheres.push_back(x[0]);
      normals_spheres.push_back(y[0]);
      normals_spheres.push_back(z[0]);
      //B
      P = (p+rings)*to_rad;
      T = t*to_rad;
      x[1] = sin(P) * cos(T);
      y[1] = sin(P) * sin(T);
      z[1] = cos(P);
      positions_spheres.push_back(R * x[1]);
      positions_spheres.push_back(R * y[1]);
      positions_spheres.push_back(R * z[1]);
      normals_spheres.push_back(x[1]);
      normals_spheres.push_back(y[1]);
      normals_spheres.push_back(z[1]);
      //C
      P = p*to_rad;
      T = (t+sectors)*to_rad;
      x[2] = sin(P) * cos(T);
      y[2] = sin(P) * sin(T);
      z[2] = cos(P);
      positions_spheres.push_back(R * x[2]);
      positions_spheres.push_back(R * y[2]);
      positions_spheres.push_back(R * z[2]);
      normals_spheres.push_back(x[2]);
      normals_spheres.push_back(y[2]);
      normals_spheres.push_back(z[2]);
      //D
      P = (p+rings)*to_rad;
      T = (t+sectors)*to_rad;
      x[3] = sin(P) * cos(T);
      y[3] = sin(P) * sin(T);
      z[3] = cos(P);
      positions_spheres.push_back(R * x[3]);
      positions_spheres.push_back(R * y[3]);
      positions_spheres.push_back(R * z[3]);
      normals_spheres.push_back(x[3]);
      normals_spheres.push_back(y[3]);
      normals_spheres.push_back(z[3]);
      positions_spheres.push_back(R * x[1]);
      positions_spheres.push_back(R * y[1]);
      positions_spheres.push_back(R * z[1]);
      normals_spheres.push_back(x[1]);
      normals_spheres.push_back(y[1]);
      normals_spheres.push_back(z[1]);
      positions_spheres.push_back(R * x[2]);
      positions_spheres.push_back(R * y[2]);
      positions_spheres.push_back(R * z[2]);
      normals_spheres.push_back(x[2]);
      normals_spheres.push_back(y[2]);
      normals_spheres.push_back(z[2]);
    }
  }
  //Bottom of the sphere
  for(float t=0; t<360.f; t+=sectors)
  {
    positions_spheres.push_back(0);
    positions_spheres.push_back(0);
    positions_spheres.push_back(-R);
    normals_spheres.push_back(0);
    normals_spheres.push_back(0);
    normals_spheres.push_back(-1);
    P = (180-rings)*to_rad;
    T = t*to_rad;
    x[1] = sin(P) * cos(T);
    y[1] = sin(P) * sin(T);
    z[1] = cos(P);
    positions_spheres.push_back(R * x[1]);
    positions_spheres.push_back(R * y[1]);
    positions_spheres.push_back(R * z[1]);
    normals_spheres.push_back(x[1]);
    normals_spheres.push_back(y[1]);
    normals_spheres.push_back(z[1]);
    P = (180-rings)*to_rad;
    T = (t+sectors)*to_rad;
    x[2] = sin(P) * cos(T);
    y[2] = sin(P) * sin(T);
    z[2] = cos(P);
    positions_spheres.push_back(R * x[2]);
    positions_spheres.push_back(R * y[2]);
    positions_spheres.push_back(R * z[2]);
    normals_spheres.push_back(x[2]);
    normals_spheres.push_back(y[2]);
    normals_spheres.push_back(z[2]);
  }
}
template <class FLOAT>
void create_flat_and_wire_sphere(FLOAT R,
                                 std::vector<FLOAT>& positions_spheres,
                                 std::vector<FLOAT>& normals_spheres,
                                 std::vector<FLOAT>& positions_wire_spheres,
                                 int prec = 36)
{
  // The smaller they are, the more precise the sphere will be
  // Must be a divisor of 360 and 180.
  const float rings = float(prec)/2;
  const float sectors = float(prec);
  const float to_rad = static_cast<float>(CGAL_PI / 180.0);
  create_flat_sphere(R, positions_spheres, normals_spheres);
  float T, P;
  float x[4],y[4],z[4];
  //Top of the sphere
  for(float t=0; t<360; t+=sectors)
  {
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(R);
    P = rings*to_rad;
    T = t*to_rad;
    x[1] = sin(P) * cos(T);
    y[1] = sin(P) * sin(T);
    z[1] = cos(P);
    positions_wire_spheres.push_back(R * x[1]);
    positions_wire_spheres.push_back(R * y[1]);
    positions_wire_spheres.push_back(R * z[1]);
    positions_wire_spheres.push_back(R * x[1]);
    positions_wire_spheres.push_back(R * y[1]);
    positions_wire_spheres.push_back(R * z[1]);
    //
    P = rings*to_rad;
    T = (t+sectors)*to_rad;
    x[2] = sin(P) * cos(T);
    y[2] = sin(P) * sin(T);
    z[2] = cos(P);
    positions_wire_spheres.push_back(R * x[2]);
    positions_wire_spheres.push_back(R * y[2]);
    positions_wire_spheres.push_back(R * z[2]);
    positions_wire_spheres.push_back(R * x[2]);
    positions_wire_spheres.push_back(R * y[2]);
    positions_wire_spheres.push_back(R * z[2]);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(R);
  }
  //Body of the sphere
  for(float p=rings; p<180.f-rings; p+=rings)
  {
    for(float t=0; t<360.f; t+=sectors)
    {
      //A
      P = p*to_rad;
      T = t*to_rad;
      x[0] = sin(P) * cos(T);
      y[0] = sin(P) * sin(T);
      z[0] = cos(P);
      //B
      P = (p+rings)*to_rad;
      T = t*to_rad;
      x[1] = sin(P) * cos(T);
      y[1] = sin(P) * sin(T);
      z[1] = cos(P);
      //C
      P = p*to_rad;
      T = (t+sectors)*to_rad;
      x[2] = sin(P) * cos(T);
      y[2] = sin(P) * sin(T);
      z[2] = cos(P);
      //D
      P = (p+rings)*to_rad;
      T = (t+sectors)*to_rad;
      x[3] = sin(P) * cos(T);
      y[3] = sin(P) * sin(T);
      z[3] = cos(P);
      positions_wire_spheres.push_back(R * x[0]);
      positions_wire_spheres.push_back(R * y[0]);
      positions_wire_spheres.push_back(R * z[0]);
      positions_wire_spheres.push_back(R * x[1]);
      positions_wire_spheres.push_back(R * y[1]);
      positions_wire_spheres.push_back(R * z[1]);
      positions_wire_spheres.push_back(R * x[1]);
      positions_wire_spheres.push_back(R * y[1]);
      positions_wire_spheres.push_back(R * z[1]);
      positions_wire_spheres.push_back(R * x[3]);
      positions_wire_spheres.push_back(R * y[3]);
      positions_wire_spheres.push_back(R * z[3]);
      positions_wire_spheres.push_back(R * x[3]);
      positions_wire_spheres.push_back(R * y[3]);
      positions_wire_spheres.push_back(R * z[3]);
      positions_wire_spheres.push_back(R * x[2]);
      positions_wire_spheres.push_back(R * y[2]);
      positions_wire_spheres.push_back(R * z[2]);
      positions_wire_spheres.push_back(R * x[2]);
      positions_wire_spheres.push_back(R * y[2]);
      positions_wire_spheres.push_back(R * z[2]);
      positions_wire_spheres.push_back(R * x[0]);
      positions_wire_spheres.push_back(R * y[0]);
      positions_wire_spheres.push_back(R * z[0]);
    }
  }
  //Bottom of the sphere
  for(float t=0; t<360.f; t+=sectors)
  {
    P = (180-rings)*to_rad;
    T = t*to_rad;
    x[1] = sin(P) * cos(T);
    y[1] = sin(P) * sin(T);
    z[1] = cos(P);
    P = (180-rings)*to_rad;
    T = (t+sectors)*to_rad;
    x[2] = sin(P) * cos(T);
    y[2] = sin(P) * sin(T);
    z[2] = cos(P);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(-R);
    positions_wire_spheres.push_back(R * x[1]);
    positions_wire_spheres.push_back(R * y[1]);
    positions_wire_spheres.push_back(R * z[1]);
    positions_wire_spheres.push_back(R * x[1]);
    positions_wire_spheres.push_back(R * y[1]);
    positions_wire_spheres.push_back(R * z[1]);
    positions_wire_spheres.push_back(R * x[2]);
    positions_wire_spheres.push_back(R * y[2]);
    positions_wire_spheres.push_back(R * z[2]);
    positions_wire_spheres.push_back(R * x[2]);
    positions_wire_spheres.push_back(R * y[2]);
    positions_wire_spheres.push_back(R * z[2]);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(0);
    positions_wire_spheres.push_back(-R);
  }
}
#endif //POLYHEDRON_DEMO_DRAW_SPHERE_H

#ifndef TRIANGULATION_ON_SPHERE_2_VIEWER_H
#define TRIANGULATION_ON_SPHERE_2_VIEWER_H
#include <QMap>
#include <CGAL/Qt/qglviewer.h>
#include <QOpenGLFunctions_2_1>
#include <QOpenGLVertexArrayObject>
#include <QOpenGLBuffer>
#include <QOpenGLShaderProgram>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Delaunay_triangulation_on_sphere_traits_2.h>
#include <CGAL/Projection_on_sphere_traits_3.h>
#include <CGAL/Delaunay_triangulation_on_sphere_2.h>
#include <list>
#include <vector>
class Viewer
  : public CGAL::QGLViewer
{
  typedef CGAL::Exact_predicates_inexact_constructions_kernel          Kernel;
  typedef Kernel::FT                                                   FT;
  typedef Kernel::Point_3                                              Point_3;
  typedef Kernel::Segment_3                                            Segment_3;
  typedef CGAL::Projection_on_sphere_traits_3<Kernel>                  Projection_traits;
  typedef CGAL::Delaunay_triangulation_on_sphere_2<Projection_traits>  Projected_DToS2;
  typedef std::list<std::vector<Point_3> >                             Subsampled_arcs;
  template <class TOS>
  void build_the_boundary(const TOS& tos)
  {
    typedef typename TOS::Geom_traits::SK                            Spherical_kernel;
    if(tos.dimension() < 2)
      return;
    typename TOS::Solid_edges_iterator it = tos.solid_edges_begin();
    for (; it != tos.solid_edges_end(); ++it)
    {
      typename TOS::Edge e = *it;
      const bool diametral_edge = CGAL::collinear(tos.construct_point(tos.point(e.first, (e.second+1)%3)),
                                                  tos.construct_point(tos.point(e.first, (e.second+2)%3)),
                                                  tos.geom_traits().center());
      subsampled_arcs.emplace_front();
      // primal
      if(!diametral_edge)
      {
        typename TOS::Arc_on_sphere_2 as = tos.segment_on_sphere(e);
        std::vector<typename Spherical_kernel::Point_3> discretization_points;
        CGAL::Triangulations_on_sphere_2::internal::subsample_arc_on_sphere_2<Spherical_kernel>(
              as, std::back_inserter(discretization_points), min_edge_size);
        subsampled_arcs.begin()->reserve(discretization_points.size());
        for(const typename Spherical_kernel::Point_3& spt : discretization_points)
          subsampled_arcs.begin()->push_back(Point_3(spt.x(), spt.y(), spt.z()));
      }
      else
      {
        const Segment_3 s = tos.segment(e);
        subsampled_arcs.begin()->push_back(s.source());
        subsampled_arcs.begin()->push_back(s.target());
      }
    }
  }
public:
  Viewer(QWidget* parent = 0);
  template <typename TOS, typename Iterator>
  void open(Iterator begin, Iterator end,
            const TOS& tos)
  {
    draw_balls = true;
    draw_inputs = false;
    subsampled_arcs.clear();
    inputs.clear();
    pos_points.clear();
    pos_lines.clear();
    pos_sphere_inter.clear();
    normals_inter.clear();
    normals_lines.clear();
    radius_ = tos.geom_traits().radius();
    center_ = tos.geom_traits().center();
    min_edge_size = 0.01 * radius_;
    std::copy(begin, end, std::back_inserter(inputs));
    build_the_boundary(tos);
    compute_elements();
    initialize_buffers();
    qDebug() << "Finished loading";
  }
  GLuint dl_nb;
protected :
  virtual void draw();
  virtual void init();
  virtual QString helpString() const;
  virtual void keyPressEvent(QKeyEvent *e);
private:
  //Shaders elements
  int vertexLocation[3];
  int normalsLocation[3];
  int centerLocation;
  int trivialCenterLocation;
  int mvpLocation;
  int mvLocation;
  int colorLocation;
  int lightLocation[5];
  std::vector<float> pos_points;
  std::vector<float> pos_lines;
  std::vector<float> pos_sphere;
  std::vector<float> pos_sphere_inter;
  std::vector<float> normals;
  std::vector<float> normals_inter;
  std::vector<float> trivial_center;
  std::vector<float> normals_lines;
  double min_edge_size;
  Subsampled_arcs subsampled_arcs;
  std::vector<Point_3> inputs;
  bool draw_inputs;
  bool draw_balls;
  enum VBO {
    SPHERE_POINTS =0,
    SPHERE_NORMALS,
    SPHERE_CENTER,
    POINTS_POINTS,
    POINTS_NORMALS,
    POINTS_CENTERS,
    EDGES_POINTS,
    SIZE_OF_VBO
  };
  enum VAO {
    SPHERE_VAO = 0,
    POINTS_VAO,
    EDGES_VAO,
    SIZE_OF_VAO
  };
  QOpenGLBuffer buffers[SIZE_OF_VBO];
  QOpenGLVertexArrayObject vao[SIZE_OF_VAO];
  QOpenGLShaderProgram rendering_program;
  QOpenGLShaderProgram rendering_program_edges;
  typedef void (APIENTRYP PFNGLDRAWARRAYSINSTANCEDARBPROC) (GLenum mode, GLint first, GLsizei count, GLsizei primcount);
  typedef void (APIENTRYP PFNGLVERTEXATTRIBDIVISORARBPROC) (GLuint index, GLuint divisor);
  PFNGLDRAWARRAYSINSTANCEDARBPROC glDrawArraysInstanced;
  PFNGLVERTEXATTRIBDIVISORARBPROC glVertexAttribDivisor;
  double radius_;
  Point_3 center_;
  void initialize_buffers();
  void compute_elements();
  void attrib_buffers(CGAL::QGLViewer*);
  void compile_shaders();
};
#endif // TRIANGULATION_ON_SPHERE_2_VIEWER_H

#include "Viewer.h"
#include <CGAL/point_generators_3.h>
#include <CGAL/squared_distance_3.h>
#include <CGAL/Exact_spherical_kernel_3.h>
#include <CGAL/Qt/CreateOpenGLContext.h>
#include "create_sphere.h"
#include <vector>
Viewer::Viewer(QWidget* parent )
  : CGAL::QGLViewer(parent)
{
  draw_balls = true;
  draw_inputs = false;
  trivial_center.push_back(0.);
  trivial_center.push_back(0.);
  trivial_center.push_back(0.);
  radius_ = 1.0;
  center_ = Point_3(0,0,0);
}
void Viewer::compile_shaders()
{
  initializeOpenGLFunctions();
  for(int i = 0; i<SIZE_OF_VBO; ++i)
    if(! buffers[i].create())
    {
      std::cerr<<"VBO Creation FAILED"<<std::endl;
      return;
    }
  for(int i = 0; i<SIZE_OF_VAO; ++i)
    if(!vao[i].create())
    {
      std::cerr<<"VAO Creation FAILED"<<std::endl;
      return;
    }
  //The sphere
  //Vertex source code
  const char vertex_source[] =
  {
    "#version 120 \n"
    "attribute highp vec4 vertex;\n"
    "attribute highp vec3 normal;\n"
    "attribute highp vec4 center;\n"
    "uniform highp mat4 mvp_matrix;\n"
    "uniform highp mat4 mv_matrix; \n"
    "varying highp vec4 fP; \n"
    "varying highp vec3 fN; \n"
    "void main(void)\n"
    "{\n"
    "   fP = mv_matrix * (vertex+vec4(center.xyz, 0.0)); \n"
    "   fN = mat3(mv_matrix)* normal; \n"
    "   gl_Position = mvp_matrix * (vertex+vec4(center.xyz, 0.0));\n"
    "}"
  };
  //Vertex source code
  const char fragment_source[] =
  {
    "#version 120 \n"
    "varying highp vec4 fP; \n"
    "varying highp vec3 fN; \n"
    "uniform highp vec4 color; \n"
    "uniform highp vec4 light_pos;  \n"
    "uniform highp vec4 light_diff; \n"
    "uniform highp vec4 light_spec; \n"
    "uniform highp vec4 light_amb;  \n"
    "uniform float spec_power ; \n"
    "void main(void) { \n"
    "   highp vec3 L = light_pos.xyz - fP.xyz; \n"
    "   highp vec3 V = -fP.xyz; \n"
    "   highp vec3 N = normalize(fN); \n"
    "   L = normalize(L); \n"
    "   V = normalize(V); \n"
    "   highp vec3 R = reflect(-L, N); \n"
    "   highp vec4 diffuse = max(dot(N,L), 0.0) * light_diff * color; \n"
    "   highp vec4 specular = pow(max(dot(R,V), 0.0), spec_power) * light_spec; \n"
    "gl_FragColor = light_amb*color + diffuse  ; \n"
    "} \n"
    "\n"
  };
  QOpenGLShader *vertex_shader = new QOpenGLShader(QOpenGLShader::Vertex);
  if(!vertex_shader->compileSourceCode(vertex_source))
  {
    std::cerr<<"Compiling vertex source FAILED"<<std::endl;
  }
  QOpenGLShader *fragment_shader= new QOpenGLShader(QOpenGLShader::Fragment);
  if(!fragment_shader->compileSourceCode(fragment_source))
  {
    std::cerr<<"Compiling fragmentsource FAILED"<<std::endl;
  }
  if(!rendering_program.addShader(vertex_shader))
  {
    std::cerr<<"adding vertex shader FAILED"<<std::endl;
  }
  if(!rendering_program.addShader(fragment_shader))
  {
    std::cerr<<"adding fragment shader FAILED"<<std::endl;
  }
  if(!rendering_program.link())
  {
    std::cerr<<"linking Program FAILED"<<std::endl;
  }
      //The edges
      //Vertex source code
      const char vertex_source_edges[] =
      {
        "#version 120 \n"
        "attribute highp vec4 vertex;\n"
        "uniform highp mat4 mvp_matrix;\n"
        "void main(void)\n"
        "{\n"
        "   gl_Position = mvp_matrix * vertex;\n"
        "}"
      };
      //Vertex source code
      const char fragment_source_edges[] =
      {
        "#version 120 \n"
        "void main(void) { \n"
        "gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0); \n"
        "} \n"
        "\n"
      };
      QOpenGLShader *vertex_shader_edges = new QOpenGLShader(QOpenGLShader::Vertex);
      if(!vertex_shader_edges->compileSourceCode(vertex_source_edges))
      {
        std::cerr<<"Compiling vertex source FAILED"<<std::endl;
      }
      QOpenGLShader *fragment_shader_edges = new QOpenGLShader(QOpenGLShader::Fragment);
      if(!fragment_shader_edges->compileSourceCode(fragment_source_edges))
      {
        std::cerr<<"Compiling fragmentsource FAILED"<<std::endl;
      }
      if(!rendering_program_edges.addShader(vertex_shader_edges))
      {
        std::cerr<<"adding vertex shader FAILED"<<std::endl;
      }
      if(!rendering_program_edges.addShader(fragment_shader_edges))
      {
        std::cerr<<"adding fragment shader FAILED"<<std::endl;
      }
      if(!rendering_program_edges.link())
      {
        std::cerr<<"linking Program FAILED"<<std::endl;
      }
}
void Viewer::initialize_buffers()
{
  rendering_program.bind();
  //The big white sphere
  vao[SPHERE_VAO].bind();
  //points of the sphere
  buffers[SPHERE_POINTS].bind();
  buffers[SPHERE_POINTS].allocate(pos_sphere.data(),
                                  static_cast<int>(pos_sphere.size()*sizeof(float)));
  vertexLocation[0] = rendering_program.attributeLocation("vertex");
  rendering_program.enableAttributeArray(vertexLocation[0]);
  rendering_program.setAttributeBuffer(vertexLocation[0],GL_FLOAT,0,3);
  buffers[SPHERE_POINTS].release();
  //normals of the sphere
  buffers[SPHERE_NORMALS].bind();
  buffers[SPHERE_NORMALS].allocate(normals.data(),
                                   static_cast<int>(normals.size()*sizeof(float)));
  normalsLocation[0] = rendering_program.attributeLocation("normal");
  rendering_program.enableAttributeArray(normalsLocation[0]);
  rendering_program.setAttributeBuffer(normalsLocation[0],GL_FLOAT,0,3);
  buffers[SPHERE_NORMALS].release();
  //center of the sphere
  buffers[SPHERE_CENTER].bind();
  buffers[SPHERE_CENTER].allocate(trivial_center.data(),
                                  static_cast<int>(trivial_center.size()*sizeof(float)));
  trivialCenterLocation = rendering_program.attributeLocation("center");
  rendering_program.enableAttributeArray(trivialCenterLocation);
  rendering_program.setAttributeBuffer(trivialCenterLocation,GL_FLOAT,0,3);
  buffers[SPHERE_CENTER].release();
  glVertexAttribDivisor(trivialCenterLocation, 1);
  glVertexAttribDivisor(normalsLocation[0], 0);
  vao[SPHERE_VAO].release();
  //The little green spheres
  vao[POINTS_VAO].bind();
  //points of the spheres
  buffers[POINTS_POINTS].bind();
  buffers[POINTS_POINTS].allocate(pos_sphere_inter.data(),
                                  static_cast<int>(pos_sphere_inter.size()*sizeof(float)));
  vertexLocation[2] = rendering_program.attributeLocation("vertex");
  rendering_program.enableAttributeArray(vertexLocation[2]);
  rendering_program.setAttributeBuffer(vertexLocation[2],GL_FLOAT,0,3);
  buffers[POINTS_POINTS].release();
  //normals of the sphere
  buffers[POINTS_NORMALS].bind();
  buffers[POINTS_NORMALS].allocate(normals_inter.data(),
                                   static_cast<int>(normals_inter.size()*sizeof(float)));
  normalsLocation[2] = rendering_program.attributeLocation("normal");
  rendering_program.enableAttributeArray(normalsLocation[2]);
  rendering_program.setAttributeBuffer(normalsLocation[2],GL_FLOAT,0,3);
  buffers[POINTS_NORMALS].release();
  //center of the sphere
  buffers[POINTS_CENTERS].bind();
  buffers[POINTS_CENTERS].allocate(pos_points.data(),
                                   static_cast<int>(pos_points.size()*sizeof(float)));
  centerLocation = rendering_program.attributeLocation("center");
  rendering_program.enableAttributeArray(centerLocation);
  rendering_program.setAttributeBuffer(centerLocation,GL_FLOAT,0,3);
  buffers[POINTS_CENTERS].release();
  glVertexAttribDivisor(centerLocation, 1);
  glVertexAttribDivisor(normalsLocation[2], 0);
  vao[POINTS_VAO].release();
  rendering_program.release();
  //The circles
  rendering_program_edges.bind();
  vao[EDGES_VAO].bind();
  buffers[EDGES_POINTS].bind();
  buffers[EDGES_POINTS].allocate(pos_lines.data(),
                                 static_cast<int>(pos_lines.size()*sizeof(float)));
  vertexLocation[1] = rendering_program_edges.attributeLocation("vertex");
  rendering_program_edges.enableAttributeArray(vertexLocation[1]);
  rendering_program_edges.setAttributeBuffer(vertexLocation[1],GL_FLOAT,0,3);
  buffers[EDGES_POINTS].release();
  vao[EDGES_VAO].release();
  rendering_program_edges.release();
}
void Viewer::compute_elements()
{
  pos_sphere_inter.clear();
  normals_inter.clear();
  pos_sphere.clear();
  normals.clear();
  trivial_center.clear();
  trivial_center.push_back(static_cast<float>(center_.x()));
  trivial_center.push_back(static_cast<float>(center_.y()));
  trivial_center.push_back(static_cast<float>(center_.z()));
  create_flat_sphere(static_cast<float>(radius_), pos_sphere, normals, 9);
  create_flat_sphere(0.001f*static_cast<float>(radius_), pos_sphere_inter, normals_inter, 36);
  pos_points.resize(0);
  pos_lines.resize(0);
  std::cout << inputs.size() << " inputs to points" << std::endl;
  // draw points as small spheres
  for(const auto& p : inputs)
  {
    pos_points.push_back(p.x());
    pos_points.push_back(p.y());
    pos_points.push_back(p.z());
  }
  std::cout << subsampled_arcs.size() << " edge arcs" << std::endl;
  // draw the primal edges
  std::size_t tot_size = 0;
  for(const auto& arc : subsampled_arcs)
    tot_size += arc.size();
  pos_lines.reserve(2 * 3 * tot_size);
  for(const auto& arc : subsampled_arcs)
  {
    for(std::size_t i=0; i<arc.size()-1; ++i)
    {
      pos_lines.push_back(arc[i].x());
      pos_lines.push_back(arc[i].y());
      pos_lines.push_back(arc[i].z());
      pos_lines.push_back(arc[i+1].x());
      pos_lines.push_back(arc[i+1].y());
      pos_lines.push_back(arc[i+1].z());
    }
  }
  setSceneRadius(radius_*1.3);
  setSceneCenter({center_.x(), center_.y(), center_.z()});
  showEntireScene();
}
void Viewer::attrib_buffers(CGAL::QGLViewer* viewer)
{
  QMatrix4x4 mvpMatrix;
  QMatrix4x4 mvMatrix;
  double mat[16];
  viewer->camera()->getModelViewProjectionMatrix(mat);
  for(int i=0; i < 16; i++)
    mvpMatrix.data()[i] = (float)mat[i];
  viewer->camera()->getModelViewMatrix(mat);
  for(int i=0; i < 16; i++)
    mvMatrix.data()[i] = (float)mat[i];
  // define material
  QVector4D        ambient(0.1f, 0.1f, 0.1f, 1.0f);
  QVector4D        diffuse( 0.9f,
                            0.9f,
                            0.9f,
                            0.0f );
  QVector4D        specular(  0.0f,
                              0.0f,
                              0.0f,
                              0.0f );
  QVector4D        position( -1.2f, 1.2f, .9797958971f, 1.0f  );
  GLfloat shininess =  1.0f;
  mvpLocation = rendering_program.uniformLocation("mvp_matrix");
  mvLocation = rendering_program.uniformLocation("mv_matrix");
  colorLocation = rendering_program.uniformLocation("color");
  lightLocation[0] = rendering_program.uniformLocation("light_pos");
  lightLocation[1] = rendering_program.uniformLocation("light_diff");
  lightLocation[2] = rendering_program.uniformLocation("light_spec");
  lightLocation[3] = rendering_program.uniformLocation("light_amb");
  lightLocation[4] = rendering_program.uniformLocation("spec_power");
  rendering_program.setUniformValue(lightLocation[0], position);
  rendering_program.setUniformValue(lightLocation[1], diffuse);
  rendering_program.setUniformValue(lightLocation[2], specular);
  rendering_program.setUniformValue(lightLocation[3], ambient);
  rendering_program.setUniformValue(lightLocation[4], shininess);
  rendering_program.setUniformValue(mvpLocation, mvpMatrix);
  rendering_program.setUniformValue(mvLocation, mvMatrix);
  rendering_program_edges.setUniformValue("mvp_matrix", mvpMatrix);
}
void Viewer::draw()
{
  glEnable(GL_DEPTH_TEST);
  QColor color;
  rendering_program.bind();
  if(draw_balls)
  {
    vao[SPHERE_VAO].bind();
    attrib_buffers(this);
    color.setRgbF(1.0f, 1.0f, 1.0f);
    rendering_program.setUniformValue(colorLocation, color);
    glDrawArraysInstanced(GL_TRIANGLES, 0, static_cast<GLsizei>(pos_sphere.size()/3), 1);
    vao[SPHERE_VAO].release();
  }
  if(draw_inputs)
  {
    vao[POINTS_VAO].bind();
    attrib_buffers(this);
    color.setRgbF(0.0f, 1.0f, 0.0f);
    rendering_program.setUniformValue(colorLocation, color);
    glDrawArraysInstanced(GL_TRIANGLES, 0,
                          static_cast<GLsizei>(pos_sphere_inter.size()/3),
                          static_cast<GLsizei>(pos_points.size()/3));
    vao[POINTS_VAO].release();
  }
  rendering_program.release();
  rendering_program_edges.bind();
  vao[EDGES_VAO].bind();
  attrib_buffers(this);
  glDrawArrays(GL_LINES, 0, static_cast<GLsizei>(pos_lines.size()/3));
  vao[EDGES_VAO].release();
  rendering_program_edges.release();
}
void Viewer::init()
{
  glDrawArraysInstanced = (PFNGLDRAWARRAYSINSTANCEDARBPROC)this->context()->getProcAddress("glDrawArraysInstancedARB");
  glVertexAttribDivisor = (PFNGLVERTEXATTRIBDIVISORARBPROC)this->context()->getProcAddress("glVertexAttribDivisorARB");
  if(!glDrawArraysInstanced || !glDrawArraysInstanced)
  {
    qDebug()<<"Missing OpenGL extensions. Demo not available.";
    return;
  }
  compile_shaders();
  compute_elements();
  initialize_buffers();
  glEnable(GL_BLEND);
  glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  glEnable(GL_POINT_SMOOTH);
  glEnable(GL_LINE_SMOOTH);
}
QString Viewer::helpString() const
{
  QString text("<h2>S i m p l e V i e w e r</h2>");
  text += "Use the mouse to move the camera around the object. ";
  text += "You can respectively revolve around, zoom and translate with the three mouse buttons. ";
  text += "Left and middle buttons pressed together rotate around the camera view direction axis<br><br>";
  text += "Pressing <b>Alt</b> and one of the function keys (<b>F1</b>..<b>F12</b>) defines a camera keyFrame. ";
  text += "Simply press the function key again to restore it. Several keyFrames define a ";
  text += "camera path. Paths are saved when you quit the application and restored at next start.<br><br>";
  text += "Press <b>F</b> to display the frame rate, <b>A</b> for the world axis, ";
  text += "<b>Alt+Return</b> for full screen mode and <b>Control+S</b> to save a snapshot. ";
  text += "See the <b>Keyboard</b> tab in this window for a complete shortcut list.<br><br>";
  text += "Double clicks automates single click actions: A left button double click aligns the closer axis with the camera (if close enough). ";
  text += "A middle button double click fits the zoom of the camera and the right button re-centers the scene.<br><br>";
  text += "A left button double click while holding right button pressed defines the camera <i>Revolve Around Point</i>. ";
  text += "See the <b>Mouse</b> tab and the documentation web pages for details.<br><br>";
  text += "Press <b>Escape</b> to exit the viewer.";
  return text;
}
void Viewer::keyPressEvent(QKeyEvent *e)
{
  if(e->key() == Qt::Key_P)
  {
    draw_inputs = !draw_inputs;
    update();
    return;
  }
  if(e->key() == Qt::Key_S)
  {
    draw_balls = !draw_balls;
    update();
    return;
  }
  QGLViewer::keyPressEvent(e);
}

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>800</width>
    <height>600</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Soupe 3D</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QGridLayout" name="gridLayout">
    <item row="0" column="0">
     <widget class="Viewer" name="viewer" native="true"/>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>800</width>
     <height>20</height>
    </rect>
   </property>
   <widget class="QMenu" name="menu_File">
    <property name="title">
     <string>&amp;File</string>
    </property>
    <addaction name="action_New"/>
    <addaction name="action_Quit"/>
   </widget>
   <addaction name="menu_File"/>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
  <action name="action_Quit">
   <property name="text">
    <string>&amp;Quit</string>
   </property>
   <property name="shortcut">
    <string>Ctrl+Q</string>
   </property>
  </action>
  <action name="action_New">
   <property name="text">
    <string>&amp;New</string>
   </property>
   <property name="shortcut">
    <string>Ctrl+O</string>
   </property>
  </action>
 </widget>
 <customwidgets>
  <customwidget>
   <class>Viewer</class>
   <extends>QWidget</extends>
   <header>Viewer.h</header>
  </customwidget>
 </customwidgets>
 <resources/>
 <connections/>
</ui>

# Created by the script cgal_create_cmake_script

project(Soupe3D)

project (Soupe3D)
set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)

find_package(CGAL REQUIRED COMPONENTS Qt5)
find_package(Qt5 REQUIRED COMPONENTS Script OpenGL Svg)

# Find includes in corresponding build directories
set(CMAKE_INCLUDE_CURRENT_DIR ON)
# Instruct CMake to run moc automatically when needed.
set(CMAKE_AUTOMOC ON)
if(NOT POLICY CMP0070 AND POLICY CMP0053)
  # Only set CMP0053 to OLD with CMake<3.10, otherwise there is a warning.
  cmake_policy(SET CMP0053 OLD)
endif()
if(POLICY CMP0071)
  cmake_policy(SET CMP0071 NEW)
endif()
# Find CGAL and CGAL Qt5
find_package(CGAL REQUIRED OPTIONAL_COMPONENTS Qt5)
# Find Qt5 itself
find_package(Qt5 QUIET COMPONENTS Script OpenGL Gui Svg)

if(CGAL_Qt5_FOUND AND Qt5_FOUND)

find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
include(CGAL_Eigen3_support)

  add_definitions(-DQT_NO_KEYWORDS)
  set(CMAKE_INCLUDE_CURRENT_DIR ON)

if(CGAL_Qt5_FOUND AND Qt5_FOUND AND TARGET CGAL::Eigen3_support)
  # Include this package's headers first

  add_executable(soupe3d soupe3d.cpp)

  include_directories(BEFORE ./ ./include)
  # ui file, created wih Qt Designer
  qt5_wrap_ui( uis Mainwindow.ui )

  add_to_cached_list(CGAL_EXECUTABLE_TARGETS soupe3d)

  #qt5_generate_moc( main.cpp Mainwindow.moc)

  target_link_libraries(soupe3d PRIVATE CGAL::CGAL CGAL::CGAL_Qt5 Qt5::Gui)

  add_executable  ( soupe3d main.cpp Viewer.cpp ${uis})

else()

  add_to_cached_list( CGAL_EXECUTABLE_TARGETS soupe3d )

  message(
    STATUS "NOTICE: This demo requires CGAL and Qt5, and will not be compiled.")

  target_link_libraries( soupe3d PRIVATE CGAL::CGAL CGAL::CGAL_Qt5 CGAL::Eigen3_support)

  include(${CGAL_MODULES_DIR}/CGAL_add_test.cmake)
  cgal_add_compilation_test( soupe3d )
else()
  message(FATAL_ERROR "Missing dependencies.")

  #:use-module (gnu packages algebra)
  

  #:use-module (guix build-system cmake))

  #:use-module (guix build-system cmake)
  #:use-module ((guix licenses) #:prefix license:))

    (inputs (list qtbase-5 qtscript qtsvg-5 cgal-5.5))

    (inputs (list qtbase-5 qtscript qtsvg-5 cgal-5.5 eigen))

    (license #f)))

    (license license:gpl3)))

                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007
 Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.
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  The licenses for most software and other practical works are designed
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  When we speak of free software, we are referring to freedom, not
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  To protect your rights, we need to prevent others from denying you
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  For example, if you distribute copies of such a program, whether
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  Developers that use the GNU GPL protect your rights with two steps:
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  For the developers' and authors' protection, the GPL clearly explains
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  The precise terms and conditions for copying, distribution and
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similar laws prohibiting or restricting circumvention of such
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  You may convey verbatim copies of the Program's source code as you
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keep intact all notices of the absence of any warranty; and give all
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and you may offer support or warranty protection for a fee.
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  A separable portion of the object code, whose source code is excluded
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  A "User Product" is either (1) a "consumer product", which means any
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  If you convey an object code work under this section in, or with, or
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  7. Additional Terms.
  "Additional permissions" are terms that supplement the terms of this
License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall
be treated as though they were included in this License, to the extent
that they are valid under applicable law.  If additional permissions
apply only to part of the Program, that part may be used separately
under those permissions, but the entire Program remains governed by
this License without regard to the additional permissions.
  When you convey a copy of a covered work, you may at your option
remove any additional permissions from that copy, or from any part of
it.  (Additional permissions may be written to require their own
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  Notwithstanding any other provision of this License, for material you
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that material) supplement the terms of this License with terms:
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    author attributions in that material or in the Appropriate Legal
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  All other non-permissive additional terms are considered "further
restrictions" within the meaning of section 10.  If the Program as you
received it, or any part of it, contains a notice stating that it is
governed by this License along with a term that is a further
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a further restriction but permits relicensing or conveying under this
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of that license document, provided that the further restriction does
not survive such relicensing or conveying.
  If you add terms to a covered work in accord with this section, you
must place, in the relevant source files, a statement of the
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  Additional terms, permissive or non-permissive, may be stated in the
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the above requirements apply either way.
  8. Termination.
  You may not propagate or modify a covered work except as expressly
provided under this License.  Any attempt otherwise to propagate or
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this License (including any patent licenses granted under the third
paragraph of section 11).
  However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the copyright
holder fails to notify you of the violation by some reasonable means
prior to 60 days after the cessation.
  Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.
  Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, you do not qualify to receive new licenses for the same
material under section 10.
  9. Acceptance Not Required for Having Copies.
  You are not required to accept this License in order to receive or
run a copy of the Program.  Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer transmission
to receive a copy likewise does not require acceptance.  However,
nothing other than this License grants you permission to propagate or
modify any covered work.  These actions infringe copyright if you do
not accept this License.  Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so.
  10. Automatic Licensing of Downstream Recipients.
  Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License.  You are not responsible
for enforcing compliance by third parties with this License.
  An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations.  If propagation of a covered
work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the
Corresponding Source of the work from the predecessor in interest, if
the predecessor has it or can get it with reasonable efforts.
  You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License.  For example, you may
not impose a license fee, royalty, or other charge for exercise of
rights granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that
any patent claim is infringed by making, using, selling, offering for
sale, or importing the Program or any portion of it.
  11. Patents.
  A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.  The
work thus licensed is called the contributor's "contributor version".
  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.
  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.
  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.
  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.
  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.
  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  You may not convey a covered
work if you are a party to an arrangement with a third party that is
in the business of distributing software, under which you make payment
to the third party based on the extent of your activity of conveying
the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory
patent license (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.
  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.
  12. No Surrender of Others' Freedom.
  If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License.  If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.
  13. Use with the GNU Affero General Public License.
  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.
  14. Revised Versions of this License.
  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.
  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.
  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.
  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.
  15. Disclaimer of Warranty.
  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
  16. Limitation of Liability.
  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.
  17. Interpretation of Sections 15 and 16.
  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.
                     END OF TERMS AND CONDITIONS
            How to Apply These Terms to Your New Programs
  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.
  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.
    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
Also add information on how to contact you by electronic and paper mail.
  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:
    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".
  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<https://www.gnu.org/licenses/>.
  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<https://www.gnu.org/licenses/why-not-lgpl.html>.

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