var doWind = false;
   function wind(amount) {
    xWind += amount/2;
    if(xWind >5.5) xWind = 5.5;
    if(xWind <-5.5) xWind = -5.5;
    if(doWind) setTimeout("wind(" + amount + ")",10);
   }
  
   var paused = false;
   function pause() { paused = !paused }
  
   var pi = 3.14159265358979;  //pi to 15sf
   function degToRad(x) { return ( x/(360/(2*pi)) ); }
   function radToDeg(x) { return ( x*(360/(2*pi)) ); }