# Polygon

VTKExamples/Java/GeometricObjects/Polygon

### Description

Java Program to Display a polygon having n edges, where n is the number of points in the polygon.

Other Languages

See (Cxx), (Python), (CSharp)

### Code

Polygon.java

    import vtk.vtkActor;
    import vtk.vtkCellArray;
    import vtk.vtkNamedColors;
    import vtk.vtkNativeLibrary;
    import vtk.vtkPoints;
    import vtk.vtkPolyData;
    import vtk.vtkPolyDataMapper;
    import vtk.vtkPolygon;
    import vtk.vtkRenderWindow;
    import vtk.vtkRenderWindowInteractor;
    import vtk.vtkRenderer;

    public class Polygon
    {
      // -----------------------------------------------------------------
      // Load VTK library and print which library was not properly loaded
      static
      {
        if (!vtkNativeLibrary.LoadAllNativeLibraries())
        {
          for (vtkNativeLibrary lib : vtkNativeLibrary.values())
          {
            if (!lib.IsLoaded())
            {
          System.out.println(lib.GetLibraryName() + " not loaded");
        }
          }
         }
         vtkNativeLibrary.DisableOutputWindow(null);
       }
       // -----------------------------------------------------------------

      public static void main(String s[])
      {

        vtkNamedColors colors = new vtkNamedColors();

        //For Actor Color
        double actorColor[] = new double[4];
        //Renderer Background Color
        double Bgcolor[] = new double[4];

        colors.GetColor("Red", actorColor);
        colors.GetColor("White", Bgcolor);

        vtkPoints Points = new vtkPoints();
        Points.InsertNextPoint(0.0,0.0,0.0);
        Points.InsertNextPoint(1.0,0.0,0.0);
        Points.InsertNextPoint(1.0,1.0,0.0);
        Points.InsertNextPoint(0.0,1.0,0.0);

        vtkPolygon Polygon = new vtkPolygon();
        Polygon.GetPointIds().SetNumberOfIds(4);
        Polygon.GetPointIds().SetId(0, 0);
        Polygon.GetPointIds().SetId(1, 1);
        Polygon.GetPointIds().SetId(2, 2);
        Polygon.GetPointIds().SetId(3, 3);

        vtkCellArray Polygons = new vtkCellArray();
        Polygons.InsertNextCell(Polygon);

        vtkPolyData PolygonPolyData = new vtkPolyData();
        PolygonPolyData.SetPoints(Points);
        PolygonPolyData.SetPolys(Polygons);

        //Create a Mapper and Actor
        vtkPolyDataMapper Mapper = new vtkPolyDataMapper();
        Mapper.SetInputData(PolygonPolyData);

        vtkActor Actor = new vtkActor();
        Actor.SetMapper(Mapper);
        Actor.GetProperty().SetColor(actorColor);
        Actor.GetProperty().SetLineWidth(5);

        //Create the renderer, render window and interactor.
        vtkRenderer ren = new vtkRenderer();
        vtkRenderWindow renWin = new vtkRenderWindow();
        renWin.AddRenderer(ren);
        vtkRenderWindowInteractor iren = new vtkRenderWindowInteractor();
        iren.SetRenderWindow(renWin);

        // Visualise the arrow
        ren.AddActor(Actor);
        ren.SetBackground(Bgcolor);

        renWin.SetSize(300, 300);
        renWin.Render();

        iren.Initialize();
        iren.Start();

      }
    }