# SpotLight

VTKExamples/Java/Lighting/SpotLight

This example places two vtkLight's with PositionalOn().

This example was inspired by Oliver Natt's question (and python script) on the VTK Users mailing list.

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

### Code

SpotLight.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.vtkLight;
    import vtk.vtkNativeLibrary;
    import vtk.vtkPanel;
    import vtk.vtkPolyDataMapper;
    import vtk.vtkPlaneSource;
    import vtk.vtkNamedColors;

    public class SpotLight 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 SpotLight() {
            super(new BorderLayout());

           vtkNamedColors Color = new vtkNamedColors();
           //For greenLight
           double greenLightColor[] = new double[4];
           //For PinkLight
           double pinkLightColor[] = new double[4];
           //Renderer Background Color
           double BgColor[] = new double[4];
           //Renderer Background1 Color
           double BgColor2[] = new double[4];

           //Change Color Name to Use your own Color
           Color.GetColor("Lawn_green",greenLightColor);
           //Change Color Name to Use your own Color
           Color.GetColor("DeepPink",pinkLightColor);
           //Change Color Name to Use your own Color for Renderer Background
           Color.GetColor("RoyalBlue",BgColor);
         //Change Color Name to Use your own Color for Renderer Background1
           Color.GetColor("SkyBlue",BgColor2);

          vtkPlaneSource PlaneSource = new vtkPlaneSource();
          PlaneSource.SetOrigin(-5.0, 0.0, 5.0);
          PlaneSource.SetPoint1(5.0, 0.0, 5.0);
          PlaneSource.SetPoint2(-5.0, 0.0, -5.0);
          PlaneSource.SetResolution(100, 100);

          vtkPolyDataMapper Mapper = new vtkPolyDataMapper();
          Mapper.SetInputConnection(PlaneSource.GetOutputPort());

          vtkActor Actor = new vtkActor();
          Actor.SetMapper(Mapper);

          vtkLight greenLight = new vtkLight();
          greenLight.PositionalOn();
          greenLight.SetPosition(-4.0, 4.0, -1.0);
          greenLight.SetColor(greenLightColor);
          greenLight.SetIntensity(0.5);

          vtkLight pinkLight = new vtkLight();
          pinkLight.PositionalOn();
          pinkLight.SetPosition(4.0, 5.0,1.0);
          pinkLight.SetColor(pinkLightColor);
          pinkLight.SetIntensity(0.6);

          renWin = new vtkPanel();
          renWin.GetRenderer().AddActor(Actor);
          renWin.GetRenderer().SetBackground(BgColor);
          renWin.GetRenderer().SetBackground2(BgColor2);
          renWin.GetRenderer().AddLight(greenLight);
          renWin.GetRenderer().AddLight(pinkLight);
          renWin.setSize(640,480);
          renWin.resetCamera();
          renWin.GetRenderer().GetActiveCamera().Azimuth(40);
          renWin.GetRenderer().GetActiveCamera().Elevation(30);
          renWin.resetCameraClippingRange();

          // 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("Spot Light");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.getContentPane().setLayout(new BorderLayout());
                frame.getContentPane().add(new SpotLight(), BorderLayout.CENTER);
                frame.setSize(400, 400);
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
              }
            });
          }
        }