Hintergrund mit Spiralen
========================
ScriptBegin
var Grafik = "Script Funktionen";

var n=36;        // Teilung 24,36
    Fill0="lightBlue";
    Fill1="red";  
    
    alpha=120;    // Transparenz 0-255
    
    //---------------------------------------
    w=360/n;     // Winkel
      
    min = 0.5;   // t Minimum
    max = 5.9;    // t Maximum
    dt  = 0.05;  // dt Schritt


var a = 1; var b = 0.9;
function fx(u){ return a*Math.exp(b*u)*Math.cos(u);}
function fy(u){ return a*Math.exp(b*u)*Math.sin(u);}



function init()
{ t.call("VarsLogBand");  t.clrDraw("VarsLogBand");
  //t.setBrush(Fill0);
  t.setPage();
  t.setAntiAliasing();
  
}

function draw()
{ //t.drawKoordSystem();
  //t.drawRaster();  
  t.goTo(0,0); t.turnTo(90);
 
  t.setNoStyle();
  t.beginPolygon();
  t.drawGraf("fx","fy");
  t.endPolygon(3);

  t.defDraw("LogBand");

  t.setPolygon(-1,-1);
  t.setRotate(w); t.addPolygon("LogBand");
  t.endPolygon(0);
  t.setPen("black",0,1); t.setBrush(Fill1,1,alpha);
  t.defDraw("LogBand");
  t.setIdentity();

  t.setScale(-1,1);
  t.setPolygon("LogBand");
  t.defDraw("LogBand1");

 // t.goTo(0,0);  t.turnTo(0);
 // t.draw("LogBand1");
   
  t.goTo(0,0); 
  for (d=0.0; d<(360); d=d+2*w)
  { t.turnTo(d); 
    t.draw("LogBand");
    t.draw("LogBand1");
  }
  
}
ScriptEnd#LogBand
