Hey guys,

I'm working on this sound reacted graphic code. When the shape fades out, you can see a cross line underneath the circles, that's because of the rectangle. And when i delete the rectangle it doesn't fade out. I didn't understand how to fix it...

PS: you might need a mic and music to see what's wrong.

Thank you.
...........................


import ddf.minim.*;

import processing.opengl.*;

PVector field;      
float x0 , y0 , z0;    
float h, a, b, c, n;  
float depth = 50;

float dir = -10;
float alpha = -500;

Minim minim;
AudioInput snd;
float snd_level;

 
void setup() {
   size(1024,500, P3D, OPENGL); 
 
  background(0);
  colorMode(HSB, 250);
  noFill();
  smooth();
   minim = new Minim(this);
  snd = minim.getLineIn(Minim.STEREO, 512);

  field = new PVector(width/2, height * 0.5);
 
  x0 = (random(50) - 25) / 2+snd_level*3;
  y0 = 1+snd_level*3;
  z0 = random(50) / 2+snd_level*3;
 
  h = 0.01;
  a = 10.0;
  b = 28.0;
  c = 8.0 / 3.0;
  n = 0;
}
 
void draw() {

 snd_level =snd.mix.level()*3;

    fill(200,50);
    float x1 = x0+h * a+snd_level*1 * (y0  - x0);
    float y1 = y0+ h * (x0  * (b+snd_level*1 - z0) - y0);
    float z1 = z0+ h * (x0* y0+  - c * z0);
  
    
  float cameraZ = -height/1;
  float cameraX = -width+snd_level*30/1;
 
  translate(width/50, height/50, -depth);
  rotateZ(PI*49.999);
  
stroke(0, 50);
  ellipse(y0*10 + field.x, x0*10 + field.y, 50*z0*5 / 100, 50*z0*5 / 100);

    alpha += dir;
    fill( 0, alpha );
    rect( 0, 0, width, height );
   
    if( alpha < 0 || alpha > 255 ) dir *= -1;

    // solution becomes next seed
   
    x0 = x1;
    y0 = y1;
    z0 = z1;
    //println((y0*10 + field.x) + " " + (x0*10 + field.y) + " " + z0*2);

}