# Vertex

VTKExamples/Java/GeometricObjects/Vertex

Java Program to Display a Vertex. The vertex is a primary zero-dimensional cell. It is defined by a single point.

Author: Bharatesh Chakravarthi Affiliation: VE Lab, Chung Ang University, Seoul, South Korea.

### Code

Vertex.java

    import java.awt.BorderLayout;
    import java.awt.event.ActionEvent;
    import java.awt.event.ActionListener;

    import javax.swing.JButton;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.SwingUtilities;

    import vtk.vtkActor;
    import vtk.vtkNativeLibrary;
    import vtk.vtkPanel;
    import vtk.vtkPoints;
    import vtk.vtkVertex;
    import vtk.vtkCellArray;
    import vtk.vtkPolyData;
    import vtk.vtkPolyDataMapper;
    import vtk.vtkNamedColors;

    public class Vertex extends JPanel implements ActionListener {
          private static final long serialVersionUID = 1L;
          private vtkPanel renWin;
          private JButton exitButton;

          // -----------------------------------------------------------------
          // 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 Vertex() {
            super(new BorderLayout());

          vtkNamedColors Color = new vtkNamedColors();

          //For Actor Color
          double ActorColor[] = new double[4];
          //Renderer Background Color
          double BgColor[] = new double[4];

          //Change Color Name to Use your own Color for Change Actor Color
          Color.GetColor("OrangeRed",ActorColor);
          //Change Color Name to Use your own Color for Renderer Background
          Color.GetColor("DarkSlateGray",BgColor);

          //Create a 3D Point
          vtkPoints Points = new vtkPoints();
          Points.InsertNextPoint(0.0,0.0,0.0);

          //Create A Vertex Which in turn represents a 3D point
          vtkVertex Vertex = new vtkVertex();
          Vertex.GetPointIds().SetId(0, 0);

          //Create a Cell Array -  a raw integer list that explicitly represents cell connectivity
          vtkCellArray Vertices = new vtkCellArray();
          Vertices.InsertNextCell(Vertex);

          //Create a PolyData  which represents a geometric structure
          //consisting of vertices, lines, polygons, and/or triangle strips
          vtkPolyData PolyData = new vtkPolyData();
          PolyData.SetPoints(Points);
          PolyData.SetVerts(Vertices);

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

          vtkActor Actor = new vtkActor();
          Actor.SetMapper(Mapper);
          Actor.GetProperty().SetPointSize(15);
          Actor.GetProperty().SetColor(ActorColor);

          renWin = new vtkPanel();
          renWin.GetRenderer().AddActor(Actor);
          renWin.resetCamera();
          renWin.GetRenderer().SetBackground(BgColor);
          renWin.resetCamera();
          renWin.resetCameraClippingRange();
          renWin.GetRenderer().GetActiveCamera().Azimuth(30);
          renWin.GetRenderer().GetActiveCamera().Elevation(30);

          // Add Java UI components
          exitButton = new JButton("Exit");
          exitButton.addActionListener(this);

          add(renWin, BorderLayout.CENTER);
          add(exitButton, BorderLayout.SOUTH);
          }

          /** An ActionListener that listens to the button. */
          public void actionPerformed(ActionEvent e) {
            if (e.getSource().equals(exitButton)) {
              System.exit(0);
            }
          }

          public static void main(String s[]) {
            SwingUtilities.invokeLater(new Runnable() {
              public void run() {
                JFrame frame = new JFrame("Vertex");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.getContentPane().setLayout(new BorderLayout());
                frame.getContentPane().add(new Vertex(), BorderLayout.CENTER);
                frame.setSize(400, 400);
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
              }
            });
          }
        }