OK...I'm very new to Processing and have tried to apply some old programming skills to this new language and for the life of me cannot understand why this simple program does not work. What I am trying to do is simply create a white rectangular block the turns on and off every .5 seconds. Here's the code I am using:

Code:

void setup ()
}
 size (300,250);
 background (0);
 fill (255);
}

void draw ()
{
 rect (50,50,200,150);
 delay (500);
 background (0); //Isn't this like a clear screen?
 delay (500);
}

What am I missing folks? Thanks in advance for the assist. I know I'm going to kick myself when someone reveals the answer.

you are missing the fact that processing only updates the screen at the end of the draw() method so you'll only ever see the blackness.

try (and this is untested)

Code:

boolean c = true;

// setup here

draw() {
  background (0);
  if (c) {
    // draw rectangle
    rect (50,50,200,150); 
  }
  // flip
  c = !c;
  // wait
  delay(500);
}
 

koogy wrote on Nov 20^th, 2008, 11:03pm:


This worked perfectly and was a very simple solution. Thanks so much. Now off to analyze the code and understand exactly why it works (btw...thanks for the remark statements).