// A simple ball that grows and shrinks
// Freeware (but please keep the reference to Tiny3D)
//
// Code inspired from:
//   Tiny3D -- simple example of an "authoring tool" in Java
//   using the VRML External Interface.
//   Kenneth B. Russell (kbrussel@media.mit.edu)

import java.applet.*;
import java.awt.*;
import java.util.*;
import vrml.external.field.*;
import vrml.external.exception.*;
import vrml.external.Node;
import vrml.external.Browser;

/**
* @author AUTHORNAME Daniel.Schneider@tecfa.unige.ch
* @version VERSIONDATA 0.1
**/

public class BallGrow extends Applet {
  
  // Browser we're using
  Browser browser;
  // Root of the scene graph (to which we add our clumps)
  Node root;
  // The set_scale field we want to work on
  EventInSFVec3f set_scale;
  // The set_translation field we want to work on
  EventInSFVec3f set_translation;

  //
  // Java Widgets
  //
  // One instance variable per slider,
  //    to tell what controls have been used
  java.awt.Scrollbar scalex;
  java.awt.Scrollbar scaley;
  java.awt.Scrollbar scalez;
  java.awt.Scrollbar transx;
  java.awt.Scrollbar transy;
  java.awt.Scrollbar transz;
  // the reset Button
  Button resetButton;
  // output
  TextArea output = null;
  // here we also could add parameters to deal with scrollbar values
  // Params to reset the ball
  float[] initScale = new float[3];
  float[] initTrans = new float[3];

  public void init () {

    //
    // Build the user interface
    //
    setBackground(new Color(0xd9d9d9));
    
    // OK this layout is very simple, but all I could figure out
    // in reasonable time :)

    // Default "as it comes" layout
    //
    add(new java.awt.Label("FeedBack Information:"));
    output = new TextArea(5, 40);
    add(output);
    add(resetButton = new Button("RESET"));

    // Initialize scale scrollbars and their labels
    // We use a sinple grid layout, i.e. all elements get the same size.
    // Not sure that I use the Scrollbar arguments in the right way (sorry)
    //
    Panel scalePanel = new Panel ();
    scalePanel.setLayout (new GridLayout (3,2));

    scalePanel.add(new java.awt.Label("X-Scale:             "));
    scalePanel.add(scalex =
		   new java.awt.Scrollbar(0, 10, 10, 1, 100));
    scalePanel.add(new java.awt.Label("Y-Scale:             "));
    scalePanel.add(scaley =
		   new java.awt.Scrollbar(0, 10, 10, 1, 100));
    scalePanel.add(new java.awt.Label("Z-Scale:             "));
    scalePanel.add(scalez =
		   new java.awt.Scrollbar(0, 10, 10, 1, 100));


    // Initialize translation scrollbars and their labels
    //
    Panel transPanel = new Panel ();
    transPanel.setLayout (new GridLayout (3,2));

    transPanel.add(new java.awt.Label("X-Translation:      "));
    transPanel.add(transx =
		   new java.awt.Scrollbar(0, 10, 10, -100, 100));
    transPanel.add(new java.awt.Label("Y-Translation:      "));
    transPanel.add(transy =
		   new java.awt.Scrollbar(0, 10, 10, -100, 100));
    transPanel.add(new java.awt.Label("Z-Translation:      "));
    transPanel.add(transz =
		   new java.awt.Scrollbar(0, 10, 10, -100, 100));

    // let's add the two panels to the applet (mother panel)
    add (scalePanel);
    add (transPanel);

    //
    // We use these parameters to reset the ball
    //
    initTrans[0] = 0.0f; initTrans[1] = 0.0f; initTrans[2] = 0.0f;
    initScale[0] = 1.0f; initScale[1] = 1.0f; initScale[2] = 1.0f;

    //
    // VRML Interface
    //
    
    // Get the browser
    browser = Browser.getBrowser(this);
  
    // Get handle to ROOT of the scene graph (which is a transform node)
    
    try {
      // get the handle for the root object and give some feedback
      root = browser.getNode("ROOT");
      output.appendText("Got root :)  \n");

      // Get the reference to the set_scale event
      set_scale = (EventInSFVec3f) root.getEventIn("scale");
      output.appendText("Got set_scale :)  \n");

      // Get the reference to the set_translation event
      set_translation = (EventInSFVec3f) root.getEventIn("translation");
      output.appendText("Got set_translation :)  \n");
    }
    catch (InvalidNodeException e) {
      output.appendText("PROBLEMS!: " + e + "\n");
    }
    catch (InvalidEventInException e) {
      output.appendText("PROBLEMS!: " + e + "\n");
    }


  }

  //
  // Callback of Java Widgets (i.e. user input to the Java applet)
  //

    public boolean handleEvent (Event event) {


      if (event.target instanceof Scrollbar) {

	//
	// First we look after the scrollbars
	// 
	
	Scrollbar bar = (Scrollbar) event.target;
	
	if ((bar == scalex) ||
	    (bar == scaley) ||
	    (bar == scalez))
	  {
	    float[] val = new float[3];
	    // Center about origin
	    val[0] = ((float) scalex.getValue()) / 10.0f;
	    val[1] = ((float) scaley.getValue()) / 10.0f;
	    val[2] = ((float) scalez.getValue()) / 10.0f;
	    
	    // write it out to the scene
	    output.appendText("Set Scale Value:" + " x=" + val[0] + " y=" + val[1] + " z=" + val[2] + "\n");
	    set_scale.setValue(val);
	  }
	else {
	  if ((bar == transx) ||
	      (bar == transy) ||
	      (bar == transz))
	    {
	      float[] val = new float[3];
	      // Center about origin
	      val[0] = ((float) transx.getValue()) / 10.0f;
	      val[1] = ((float) transy.getValue()) / 10.0f;
	      val[2] = ((float) transz.getValue()) / 10.0f;
	      
	      // write it out to the scene
	      output.appendText("Set Trans Value:" + " x=" + val[0] + " y=" + val[1] + " z=" + val[2] + "\n");
	      set_translation.setValue(val);
	    }}

	return true;
      }
      else {
	//
	// The User want's to reset the scene
	//
	if (event.target instanceof Button) {
	  Button b = (Button) event.target;
	  // if (b.getLabel() == "RESET") ... i like the following better
	  if (b == resetButton)
	    {
	      set_scale.setValue(initScale);
	      set_translation.setValue(initTrans);
	    }
	  return true;
	}
      }
      // hmm not sure what this does 
      return super.handleEvent(event);
    }
    
}