void setup() {
  size(400,400);
  smooth();
  frameRate(15);
  background(0);
}

void draw()
{
  fadeAway();                // move the execution to the function
  drawRandomL();        // move the execution to the function
}

// Paint a transparent black rectangle over window
void fadeAway()
{
  fill(0,20);
  rect(0,0,width,height);
}

// draw random L shape
void drawRandomL()
{
  fill(random(128,255),random(128,255),random(128,255));
  drawL(random(width),random(height),random(50,150));
}

// Draw a L shape at the given position and of a given size
void drawL(float x, float y, float s)
{
  beginShape();
  vertex(x,y);
  vertex(x,y+s);
  vertex(x+s,y+s);
  vertex(x+s,y+s/2);
  vertex(x+s/2,y+s/2);
  vertex(x+s/2,y);
  endShape(CLOSE);
}

// START NO NOTES
// code used to capture screenshots
void keyReleased() {
  if(key == '`' && !online) save("sketch.png");
}