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Index › Programming Questions & Help › Syntax Questions › quick qn about for loop..
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quick qn about for loop.. (Read 731 times)
tavern
quick qn about for loop..
Aug 30th, 2009, 4:42am  
hi.. i want to draw some circles using a class.. but i cant seem to draw them with a time delay between each one using the for loop..
the code below starts with one circle then nothing happens for a while and the rest of the circles appear altogether suddenly..
how do i control the time delay so that they will appear one by one slowly?

Code:

CIRCLES circles = new CIRCLES(); 

void setup()
{
  size(500,500);
  background(0);
}

void draw()
{
  circles.drawcircles();
}

class CIRCLES
{
  void drawcircles()
  {
    int x = width/10;
    for(int i=0;i<=x;i++)
    {
       ellipse( x*i,height/2, 50,50);
       delay(50);
    }
  }
}
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PhiLho 
Re: quick qn about for loop..
Reply #1 - Aug 30th, 2009, 6:31am  
Classical problem with delay(): draw() will show something on screen only after all the code inside (including loops and delays...) is finished. At it will display all the resulting drawings at once!

Classical workaround: check time (or frame count), after a given time (current time - start time > given time), increment a counter and display the nth circle (and those before, if you use background()).
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