Cubetube - Its hip to be cube

Update Demo
Cube cube = Cube();
int y[4], x[4], z[4], Dcolor;



void setup()
{
  cube.begin();
  cube.background(black);
  Dcolor = 0;
  for(int i; i<5; i++)
  {
   x[i] = 0;
   y[i] = 0;
   z[i] = 0;
  }

}
        
void loop()
{

  
  x[4] = random(0,8);
  y[4] = random(0,8);
  z[4] = random(0,8);


  cube.line(x[1],y[1],z[1],x[0],y[0],z[0],Color(0,0,0));
  cube.line(x[2],y[2],z[2],x[1],y[1],z[1],cube.colorMap(Dcolor-2,0,19));
  cube.line(x[3],y[3],z[3],x[2],y[2],z[2],cube.colorMap(Dcolor-1,0,19));
  cube.line(x[4],y[4],z[4],x[3],y[3],z[3],cube.colorMap(Dcolor,0,19));

  Dcolor = (Dcolor+1)%20;
  cube.show();
  delay(100);
  
  
  for(int i=0; i<4; i++)
  {
    x[i] = x[i+1];
    y[i] = y[i+1];
    z[i] = z[i+1];
  }
    

}