int u = 80;
float a = -.1;

void setup() {
  size(500,500);
  background(0);
  fill(255,20);
  stroke(255);
  smooth();
}

void draw() {
  background(0);
  Curlicue (mouseY, mouseX, a);
}


void Curlicue(int xpos, int units, float angle) {
  translate(xpos, 0);
  for (int i = units; i > 0; i--) {
  line(xpos,0,0,xpos);
  rotate(angle);
  }

}