#VRML V2.0 utf8   3D Lissajous bands, Evgeny Demidov   1 May 2000

NavigationInfo{ type "EXAMINE" }
Background{ skyColor 0 0 0.75 }
DEF BandClock TimeSensor{ cycleInterval 60 loop TRUE }   #Time of cicle
DEF Animation OrientationInterpolator {
   key [ 0, .33, .66, 1 ]
   keyValue [ 0 1 0 0, 0 1 0 2.1, 0 1 0 4.2, 0 1 0 0 ] }
DEF XForm Transform{ scale 2 2 2
  children[
    Shape{
      appearance Appearance{ material Material{ diffuseColor 1 1 1 } }
      geometry DEF scrIFS IndexedFaceSet{
         coord DEF scrCoord Coordinate{}
         creaseAngle 2 } }
    Shape{
      appearance Appearance{ material Material{ diffuseColor 1 0 0 } }
      geometry DEF scrIFSside2 IndexedFaceSet{
         coord USE scrCoord
         creaseAngle 2 } }
  ]
}

DEF SCR Script{
  eventIn SFTime go
  field SFNode scrIFS USE scrIFS
  field SFNode scrIFSside2 USE scrIFSside2
  field SFNode scrCoord  USE scrCoord
  directOutput TRUE
url ["javascript:

function initialize() { 
  j=3, k=2+0.3, l=1-0.03, m=1;        //  parameters
  n=100, r=1, d=0.3, step=6.283 / (n-1), t=0;
  p = new MFVec3f();    p.length = 2*n;
  for (var i= 0; i< n; i++) {
    fi=i*step;
    x=r*Math.cos(fi*j);
    y=r*Math.sin(fi*k);    dy=d*Math.sin(fi*m);
    z=r*Math.cos(fi*l);    dz=d*Math.cos(fi*m);
    p[t].x = x;   p[t].y = y+dy;   p[t++].z = z+dz;
    p[t].x = x;   p[t].y = y-dy;   p[t++].z = z-dz; }
  var c = new MFInt32( );  c.length = 8*(n-1);
  t=0;
  for (var i= 0; i< 2*(n-1); i+=2) {
    c[t++] = i;    c[t++] = i+1;  c[t++] = i+2;  c[t++] = -1;
    c[t++] = i+1;  c[t++] = i+3;  c[t++] = i+2;  c[t++] = -1;}
  scrCoord.set_point = p;
  scrIFS.set_coordIndex = c;
  t=0;
  for (var i= 0; i< 2*(n-1); i+=2) {
    c[t++] = i+1;  c[t++] = i;    c[t++] = i+2;  c[t++] = -1;
    c[t++] = i+3;  c[t++] = i+1;  c[t++] = i+2;  c[t++] = -1;}
  scrIFSside2.set_coordIndex = c;
}
function go(){
  for (var i=0; i<2*n-2; i++)  p[i] = p[i+2];
  fi += step;
  x=r*Math.cos(fi*j);
  y=r*Math.sin(fi*k);    dy=d*Math.sin(fi*m);
  z=r*Math.cos(fi*l);    dz=d*Math.cos(fi*m);
  p[n+n-2] = new SFVec3f(x, y+dy, z+dz);
  p[n+n-1] = new SFVec3f(x, y-dy, z-dz);
  scrCoord.set_point = p;
}
"]
}
ROUTE BandClock.time TO SCR.go
ROUTE BandClock.fraction_changed TO Animation.set_fraction
ROUTE Animation.value_changed TO XForm.rotation