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Index › Programming Questions & Help › Syntax Questions › wait() function

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wait() function? (Read 4195 times)

rabidmachine9

wait() function?
May 30^th, 2009, 2:51pm

hello everybody!
do you know if there is a function that would freeze the program from running but will display the screen?
I have already used delay() but what it probably does is freezing the screen and not the program from runing.
I am actualy trying to visualize a sorting algorithm and I want the changes to be visible after each iteration....

thanks in advance!

Scott Murray Full Member Offline Posts: 117 San Francisco	Re: wait() function? Reply #1 - May 30^th, 2009, 4:07pm So, do you want to make sure everything stops? The easiest way is to set frameRate() to something really slow, like 1 or 2 frames per second. Another way is to just set up a while() loop that watches the time in millis(). Then, let the while() loop finish once millis() == whatever number.

PhiLho YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: wait() function? Reply #2 - May 31^st, 2009, 12:49am See Re: pause within draw() , but you makes it conditional instead of depending on user input. Well, perhaps you need to ask the user to do something (press a key, click...) to restart the cycle, because you might have trouble to make it restart after a while...

rabidmachine9

Re: wait() function?
Reply #3 - May 31^st, 2009, 5:10am

Thanks for all the replies guys!
I tried what you suggest and I don't think it's exactly what I want...
this is the code...
it will look a bit fancier in its final form but the idea is that you first create some rectangles(in this case 50) with random width and tou display them on the screen and then the program starts to sort them by width length and I would like the picture and the code to freeze in every sorting step so everybody can visualize the procedure...

_{int numRects = 50;
// Declare the array
RectElem[] rectArray ;

void setup(){
background(242, 204, 47);
size(500,500);
noLoop();

rectArray = new RectElem[numRects]; //create the array
for(int index = 0;index < numRects;index++){
rectArray[index] = new RectElem(); //initialize the array
}
}

void draw(){

int count = 0;

for(int index = 0;index < numRects;index++){//draw some rectangles

fill(100,100,100);
//if ( rectArray[index] != null)
rectArray[index].rectWidth = random(500);
//if ( rectArray[index] != null)
rectArray[index].yPos = count;
//if ( rectArray[index] != null)
rectArray[index].create();
count += 10;

}

shortArrayBubble(rectArray, numRects);

}

void shortArrayBubble(RectElem array[], int elems){//sort the rectangles by size
float temp;
boolean swap = true;

while(swap)
{
swap = false;
for (int count = 0; count < (elems - 1); count++){

if (array[count].rectWidth > array[count + 1].rectWidth){
temp = array[count].rectWidth;
array[count].kill();
array[count].rectWidth = array[count + 1].rectWidth;
array[count].create();
array[count +1].kill();
array[count + 1].rectWidth = temp;
array[count + 1].create();

swap = true;

}
}
}
}

class RectElem{ //simple class for creating and killing rectangles
//int xPos;
int yPos;
// float rectHeight;
float rectWidth;

void create(){
noStroke();
fill(100,100,100);
rect(0,yPos,rectWidth,10);
}

void kill(){
noStroke();
fill(242, 204, 47);
rect(0,yPos,rectWidth,10);
}

}}

Scott Murray

Re: wait() function?
Reply #4 - May 31^st, 2009, 1:50pm

Looks like you are sorting them all at once, inside shortArrayBubble(). But the way Processing works, everything inside draw() is completed first, and then at the end of draw(), a new "frame" is drawn to the screen.

So, you need to rewrite shortArrayBubble() to something like incrementalSort(), that would just choose one rect (for example), and put it in the right place, then move to the next one, then the next one, etc. So instead of calling shortArrayBubble() once, and then you're done, call incrementalSort() once per loop through draw().

Once that's working, use frameRate() to set a speed that you like, say 2 fps.

rabidmachine9 YaBB Newbies Offline Posts: 9	Re: wait() function? Reply #5 - May 31^st, 2009, 2:03pm So, if I get it right, I would have to sort just one in every time the draw() function is called and and put a low frame rate? thanks a lot I will try that

Scott Murray Full Member Offline Posts: 117 San Francisco	Re: wait() function? Reply #6 - May 31^st, 2009, 4:15pm Yes, that's a much more succinct way of putting it. Good luck!

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