Part One: The Scene Graph

Part Two: The VRML Source Code (transtst.wrl)

Here is the entire VRML 2.0 source code. Type (or paste) this code into a file called "transtst.wrl".

#VRML V2.0 utf8

#  transtst.wrl : example of a simple animation of a cone. When
#  it is clicked it starts/stops rotating.
#  Written By : John DeCuir
#               Sony pictures Imageworks

#here is the cone 
DEF CONE_TRANS Transform {
  translation 0 3 0
  children [
    DEF TOUCH_SENSOR TouchSensor {} # Mouse click control
    DEF CONE Shape {
      appearance Appearance {
        material Material {
          emissiveColor 0.5 0 0        }
      }
      geometry Cone { height 2 bottomRadius 1 }
    }
  ]
}

#script for the animation
DEF CONE_SCRIPT Script {
  url "transtst.class"
  scriptType "javabc"
  field SFNode the_cone_trans USE CONE_TRANS
  eventIn SFBool clicked
  eventIn SFTime move
  eventOut SFBool setTimerEnabled
}

#The all-important time event generator
DEF HOURGLASS TimeSensor {
  loop TRUE
  enabled FALSE
  cycleInterval 0.2
  stopTime -1
}

#Route for the mouse click
ROUTE TOUCH_SENSOR.isActive TO CONE_SCRIPT.clicked
#Route for the timer to call "move" each time an event occurs
ROUTE HOURGLASS.time TO CONE_SCRIPT.move
#Route to enable or disable the timer
ROUTE CONE_SCRIPT.setTimerEnabled TO HOURGLASS.set_enabled

Part Three: The Java Source Code (transtst.java)

Here is the Java source code. Type this into a file called "transtst.java".

/*
   transtst.java : example of a simple animation of a cone. When
   it is clicked it starts/stops rotating.
   Written By : John DeCuir
                Sony pictures Imageworks
*/ 
import vrml.*;
import vs.*;

public class transtst extends Script {
  SFNode coneTransN = (SFNode)getField("the_cone_trans");
  Transform coneTrans = (Transform)coneTransN.getValue();
  float newTrans[] = new float[4];
  float transPt[] = new float[3];
  // setTimerEnabled changes "enabled" field of the TimeSensor 
  // since we have a set up a route to do this
  SFBool setTimerEnabled = (SFBool) getEventOut("setTimerEnabled");
  boolean timerOn;

  public transtst() {
    timerOn = false;
    // set up rotation axis and angle 
    newTrans[0] = 1;
    newTrans[1] = 0;
    newTrans[2] = 0;
    newTrans[3] = 10;    // degrees
    // set up centre of rotation
    transPt[0] = 0;
    transPt[1] = 2;
    transPt[2] = 0;
  }
  
  // clicked() is called when the mouse is clicked
  public void clicked(ConstSFBool ev, ConstSFTime time) {
    if (ev.getValue() == true) {
      return;
    } else {
      if (timerOn == false) {
        setTimerEnabled.setValue(true); 
        timerOn = true;
      } else {
        setTimerEnabled.setValue(false);
        timerOn = false;
      }
    }
  }

  // move() is called at each time event. It calls a Java
  // function which rotates the cone 
  public void move(ConstSFTime ev, ConstSFTime time) {
    coneTrans.rotateAroundLineDegree(newTrans,
                             transPt, coneTrans.modeRelative);  
  }    
}