How to freeze a draw loop?

Processing Beginners
1

I have a draw loop that makes a new graphic each time. I want to be able to pause the loop by clicking the mouse when I see a graphic that I like. But everything I’ve tried fails to stop on the current frame. It’s always the next frame, or a later one, no matter how slow the frame rate. For example,

if (mousePressed == true) { delay(20000); }

pauses things for 20 seconds, but it seems to take a frame or two until things stop.

I haven’t found any info that addresses this sort of thing…I’m doing something wrong. Suggestions?

2 
// Discourse.Processing.org/t/how-to-freeze-a-draw-loop/2741/2
// GoToLoop (2018-Aug-18)

static final int DELAY = 5 * 1000; // 5 seconds
static final float FPS = .5; // 2 seconds

void setup() {
  size(300, 150);
  frameRate(FPS);
}

void draw() {
  getSurface().setTitle("Frame: " + frameCount);
  background((color) random(#000000));
}

void mousePressed() {
  pauseFrame();
}

void pauseFrame() {
  delay(DELAY);
}
3

You can use loop() and noLoop(). You can find hem in the reference. Another way, which is not documented in the reference, is to do this:

void mousePressed(){
   looping =  !looping;  //EDIT******
}

This toggles between loop and noLoop, exactly as I suggested in the first line. however, this way is more straight forward. Not sure if it will stop right at the frame that you want. Just give it a try and see if it works for you.

Kf

1 Like
4

This works! Thank you!

5

I get an error: Syntax error on token"!=", invalid AssignmentOperator

But the other suggestion works. Thanks!

1 Like
6

Should be instead: looping = !looping; or looping ^= true; :nerd_face:

7

This seems to stop it on the next frame, not the current one. :face_with_raised_eyebrow:

8

My mistake… I will correct my post.

We will need to see some code to see if it is possible to store your current state, or use another approach different to looping.

Kf