/* 
   
   Structure 2 
   
   A grid of points in the top half of the surface. 
   Each point moves downward and returns to the top when it falls off the 
   bottom edge. Beginning in the upper-left, each row and column moves 
   faster than the previous one. The speeds combine so that the point in the 
   upper-left is the slowest and the point in the lower-right is the 
   fastest. Copy and flip the grid across a central vertical axis and 
   display simultaneously. 
 
   Implemented by Casey Reas <http://groupc.net> 
   16 April 2004 
   Processing v.68 <http://processing.org> 
 
*/ 
 
Pixel[] pix; 
 
void setup() 
{ 
  size(800, 600); 
  pix = new Pixel[width/10 * height/20]; 
  framerate(30); 
  
  for(int i=0; i<width/10; i++) { 
    for(int j=0; j<height/20; j++) { 
      pix[i*(height/20)+j] = new Pixel(i*10, j*10, i/100.0*j/100 * 8.0, true); 
    } 
  } 
} 
 
void loop() 
{ 
  background(0); 
  for(int i=height/10; i<(height/20 * width/10); i++) { 
    pix[i].update(); 
    pix[i].display(); 
  } 
} 
 
class Pixel 
{ 
  float x; 
  float y; 
  float speed; 
  float count; 
  float angle; 
  boolean curve; 
 
  Pixel(float x, float y, float speed, boolean curve) { 
    this.x = x; 
    this.y = y; 
    this.speed = speed; 
    this.curve = curve; 
  } 
  
  void update() { 
    y+=speed; 
    if(y > height) { 
      y = 0; 
    } 
  } 
  
  void display() { 
    stroke(255); 
      point(x, y+5); 
      point(width-x, y+5); 
  } 
 
}