// Re-draw 
// by REAS <http://reas.com> 

// The statements in the setup() function 
// execute once when the program begins 
void setup() 
{ 
  size(200, 200);  // Size should be the first statement 
  stroke(255);     // Set line drawing color to white 
  framerate(30); 
  noLoop(); 
} 
 
float y = 100; 
 
// The statements in draw() are executed until the 
// program is stopped. Each statement is executed in 
// sequence and after the last line is read, the first 
// line is executed again. 
void draw() 
{ 
  background(0);   // Set the background to black 
  y = y - 1; 
  if (y < 0) { y = height; } 
  line(0, y, width, y);  
} 
 
void mousePressed() 
{ 
  redraw(); 
}