// sine wave static
int a=20;

void setup(){
  size(320,240);
  noFill();
}

void draw(){
  a = mouseX;
  background(255);
  for(int x=0-a; x<width+a; x+=5){
    pushMatrix();
    translate(x,0);
    for(int y=0; y<height; y++){
      float s = sin(radians(y));
      point(s*a,y);
    }
    popMatrix();
  }
}