How to pause/play a sketch with the same button?

s_diaconu

Hi guys, I'm trying to implement a pause/play for a sketch with the same key, for example if I press p the sketch should stop and if I press p again, the sketch should start again. So far I used the noLoop()/loop() to do this but with two different keys (p for pause, r for start). It does work if I use keyPressed() and keyReleased() but this means to hold down the key but this doesn't answer my question. Also in the pause mode I used redraw() for a single step while noLoop() and works good. Here is some code I tried so far with two different keys:

public void keyPressed(){

if ( key == 'p' )
    noLoop();
if ( key == 'r' )
    loop();
if ( key == 's' )
    redraw();

}

And this is the code with the same key:

public void keyPressed(){

if ( key == 'p' )
    noLoop();
if ( key == 'p' )
    loop();
if ( key == 's' )
    redraw();

}

In this case when I press key it doesn't have any effect. And the last one I tried is this:

public void keyPressed(){

if ( key == 'p' )
    noLoop();
else
    loop();
if ( key == 's' )
    redraw();

}

In this case when I press 'p' it stops the sketch but is doesn't play again. Because of the 'else' it plays again when I press any key including 's' which suppose to be just for a single step. Any help is more than welcome. Thanks!

GoToLoop

/** 
 * Looping Pause (v1.1)
 * GoToLoop (2017/Jul/19)
 *
 * Forum.Processing.org/two/discussion/23531/
 * how-to-pause-play-a-sketch-with-the-same-button#Item_1
 */

void setup() {
  size(800, 600);
  frameRate(4);
}

void draw() {
  background((color) random(#000000));
}

void keyPressed() {
  final int k = keyCode;
  looping ^= k == 'P';
  redraw = k == 'S';
}

Chrisir

Is looping a keyword or do we have to evaluate it?

kfrajer

This is what I would do in your case.

Kf

if ( key == 'p' )
    looping = !looping;

if ( key == 's' && looping==false )
    redraw();

Chrisir

if(looping){

if(key=='p'){

looping=false;

noLoop();

}

else {

// looping is false

if(key=='p'){

looping =true;

loop ();

}//if

}//else

s_diaconu

Thanks guys. All your answers work good.