import processing.pdf.*;

int numX = 20;
int numY = 10;
int unit = 40;
float offset = unit/8;
boolean record = false;

void setup()
{
  size(numX*unit,numY*unit);
  noFill();
  //noStroke();
  stroke(0);
  //fill(0);
  smooth();
}

void draw()
{
    if (record) {
    beginRecord(PDF, "frame-####.pdf"); 
  }
  background(255);
  for(int i=0; i<numX; i++) {
    for(int j=0; j<numY; j++) {
      float x = unit/2+(i*unit);
      float y = unit/2+(j*unit);
      float dis = distance(x,mouseX,y,mouseY);
      float dia1 = map(dis,0,width,1,unit+(offset*2));
      float dia2 = (dia1 > unit) ? dia1+offset : unit+offset;
      ellipse(x,y,dia1,dia1); 
      ellipse(x,y,dia2,dia2); 
    } 
  }
  if (record) {
    endRecord();
	record = false;
  }
}

float distance(float x1, float x2, float y1, float y2) {
  float dist = sqrt(sq(x1-x2)+sq(y1-y2));
  return dist;
}

void mousePressed() {
  record = true;
}