prime spiral spin

int A[]; // prime number container
int count=1;// no of primes allocated
int i;// loop variable declared global to preserve memory
int x;//co ordinate
int y;//co ordinate
int c = 1;// starting point
int step=1;// the upper limit that describes how far must (x,y) traverse to make the outer edge of the spiral
int direction = -1; // simple variable that reverses the direction after every horizontal and vertical spiral edge draw.  (x++,y) X //step, (x,y++) X step. then (x--,y) X step, (x,y--) X step step++ and repeat.
int s = 0;// remove for v1.2, keep for v 1.1
int imgno=1;//  offset
int p; // spiral overflow variable

void setup()
{
  size(600, 600);
  orientation(LANDSCAPE);
  background(255);
  A = new int[4000000];
  A[0]=2;
  x=width/2;
  y=height/2;

  /*while ( (s++)<c)
   {
   prime(s);
   //println(s);
   }*/
}

void draw()
{
  background(255);
  p=1;
  c=imgno;
  //s=0;
  x=width/2;
  y=height/2;
  step = 1;
  println("point1");
  if (prime(c))
    point(x, y);


  while (p<=360200)
  {
    direction*=-1;

    for (int d=0;d<step;d++)
    {
      x=x+direction;
      c=c+1;
      p++;
      if (prime(c))
        point(x, y);
      println("point = "+x+","+y);
    }
    for (int d=0;d<step;d++)
    {
      y=y+direction;
      c=c+1;
      p++;
      if (prime(c))
        point(x, y);
      println("point = "+x+","+y);
    }
    println("step= "+step);
    step++;
  }
  imgno++;
  //save("prime"+imgno+".jpeg");
  delay(20);
}

boolean prime(int n)
{
  if (n==1)
    return false;
  else if (n==2)
    return true;
  else
  {
    for (int i=0;((i<count)&&(A[i]<=sqrt(n)));i++)
    {
      println("A["+i+"]"+"="+A[i]+"    n= "+n);
      if (n%A[i]==0)
        return false;
    }
  }
  A[count] = n;
  count++;
  return true;
}