void setup() {
  size(256,256,P3D);
  background(200);
  framerate(60);
}
class Point {
  float x,y,z;
}

Point points[] = new Point[80];
int cp = 0;

void draw() {
  background(200);  
  cp++;
  if (cp>=points.length)
    cp = 0;
  if (points[cp]==null)
    points[cp] = new Point();
  points[cp].x = mouseX;
  points[cp].y = mouseY;
  points[cp].z = 0;
  
  //lights();
  noStroke();
  beginShape(QUAD_STRIP);
  for (int i=0; i<points.length; i++) {
    fill((points.length-i)*256/points.length);
    Point p = points[(cp-i+points.length)%points.length];
    if (p==null) break;
    //curveVertex(p.x,p.y,p.z);
    vertex(p.x,p.y,p.z);
    vertex(p.x,p.y,p.z-50);
    p.z+=4f;
    //p.x=(p.x-width/2)*1.05f+width/2;
    //p.y=(p.y-height/2)*1.05f+height/2;
  }
  endShape();
  
}