LED Panel with 64x32 Leds controlled by Arduino board

After sneaking and testing, got this:

function ellipse(int xm, int ym, int a, int b)
{
   var dx = 0;
   var dy = b;
   var a2 = a*a
   var b2 = b*b;
   var err = b2-(2*b-1)*a2
   var e2; /* Fehler im 1. Schritt */

   do {
       g.setPixel(xm+dx, ym+dy); 
       g.setPixel(xm-dx, ym+dy); 
       g.setPixel(xm-dx, ym-dy); 
       g.setPixel(xm+dx, ym-dy); 

       e2 = 2*err;
       if (e2 <  (2*dx+1)*b2) { dx++; err += (2*dx+1)*b2; }
       if (e2 > -(2*dy-1)*a2) { dy--; err -= (2*dy-1)*a2; }
   } while (dy >= 0);

   while (dx++ < a) { 
       g.setPixel(xm+dx, ym); 
       g.setPixel(xm-dx, ym);
   }
}

@Gordon, would it be worth the effort (original source )?

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