// Written by: Chris Weigle
// Date: November 15, 2003

import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.*;

/* SphereLight - illuminate a hemisphere on a plane. Light vector tracks the
 * mouse. View vector is fixed at z+. All calculations use the same light
 * vector (infinite light source) and the same view vector (infinite viewer).
 * It's faster, but still looks okay.
 */

public class SphereLightApplet extends JApplet
 {
    public void init()
    {
      final SphereLightPanel sp = new SphereLightPanel();
      final JColorChooser chooser = new JColorChooser();

      chooser.setPreviewPanel(new JPanel());
      chooser.getSelectionModel().addChangeListener(new ChangeListener()
      {
        public void stateChanged(ChangeEvent event)
        {
          chooser.getColor().getRGBColorComponents(sp.color);
          sp.illumination();
          sp.repaint();
        }
      });

      JPanel panel = new JPanel();
      panel.setLayout(new GridLayout(4, 2));

      JLabel label = new JLabel("Ambient Term (ka):");
      JFloatSlider slider = new JFloatSlider(0.f, 1.f, sp.ka, .2f);
      getContentPane().add(slider, BorderLayout.NORTH);
      slider.addChangeListener(new ChangeListener()
      {
        public void stateChanged(ChangeEvent event)
        {
          JFloatSlider slider = (JFloatSlider)event.getSource();
          if (!slider.getValueIsAdjusting())
          {
            sp.ka = slider.getFloatValue();
            sp.illumination();
            sp.repaint();
          }
        }
      });
      panel.add(label);
      panel.add(slider);

      label = new JLabel("Diffuse Term (kd):");
      slider = new JFloatSlider(0.f, 1.f, sp.kd, .2f);
      getContentPane().add(slider, BorderLayout.NORTH);
      slider.addChangeListener(new ChangeListener()
      {
        public void stateChanged(ChangeEvent event)
        {
          JFloatSlider slider = (JFloatSlider)event.getSource();
          if (!slider.getValueIsAdjusting())
          {
            sp.kd = slider.getFloatValue();
            sp.illumination();
            sp.repaint();
          }
        }
      });
      panel.add(label);
      panel.add(slider);

      label = new JLabel("Specular Term (ks):");
      slider = new JFloatSlider(0.f, 1.f, sp.ks, .2f);
      getContentPane().add(slider, BorderLayout.NORTH);
      slider.addChangeListener(new ChangeListener()
      {
        public void stateChanged(ChangeEvent event)
        {
          JFloatSlider slider = (JFloatSlider)event.getSource();
          if (!slider.getValueIsAdjusting())
          {
            sp.ks = slider.getFloatValue();
            sp.illumination();
            sp.repaint();
          }
        }
      });
      panel.add(label);
      panel.add(slider);

      label = new JLabel("Specular Exponent (ksp):");
      slider = new JFloatSlider(0.f, 50.f, sp.ksp, 10.f);
      getContentPane().add(slider, BorderLayout.NORTH);
      slider.addChangeListener(new ChangeListener()
      {
        public void stateChanged(ChangeEvent event)
        {
          JFloatSlider slider = (JFloatSlider)event.getSource();
          if (!slider.getValueIsAdjusting())
          {
            sp.ksp = slider.getFloatValue();
            sp.illumination();
            sp.repaint();
          }
        }
      });
      panel.add(label);
      panel.add(slider);

      getContentPane().setLayout(new FlowLayout());

      JTabbedPane tabs = new JTabbedPane();
      tabs.addTab("Colors", chooser);
      tabs.addTab("Parameters", panel);
      getContentPane().add(sp);
      getContentPane().add(tabs);
    }

    class JFloatSlider extends JSlider
    {
      private final int SCALE = 100;
      public JFloatSlider(float min, float max, float init, float tick)
      {
        this.setPaintLabels(true);
        this.setPaintTicks(true);

        setMinimum((int)(min*SCALE));
        setMaximum((int)(max*SCALE));
        this.setValue((int)(init*SCALE));

        Hashtable ht = new Hashtable();
        for (float i = min; i <= max; i+=tick)
        {
          JLabel l = new JLabel(""+i);
          ht.put(new Integer((int)Math.rint(i*SCALE)), l);
        }
        this.setLabelTable(ht);

        this.setMinorTickSpacing((int)(tick * SCALE / 4));
      }
      public float getFloatValue() { return (float)getValue()/(float)SCALE; }
    }
}