void setup() {
  size(400, 400);
  smooth();
  background(255);
}

void draw() {
  stroke(0, 30);
  fill(0, 255, 0, 20);
  drawPosCircles(mouseX, mouseY, 50);
  fill(255, 0, 0, 20);
  drawPosCircles(mouseX, 100, 70);
}

void drawPosCircles(float x, float y, float s) {
  ellipse(x, y, s, s);
  ellipse(x, y, s - 10 , s - 10);
  ellipse(x, y, s - 20, s-20);
}