Hi,

I've written a short piece of code which checks when a mouse button is pressed and is supposed to animate an ellipse growing from the mouseX and mouseY positions.

To do this I've used a recursive function that should draw an ellipse every 100 milliseconds.  Unforunately I'm getting stack overflows and I'm not sure why.  Can anyone suggest where I'm going wrong?  The code is printed below:

void setup() {
 background(0);
 fill(255);
 stroke(255);
}

void draw(){
}

void mousePressed(){
 generateCircle(mouseX,mouseY,millis(),50,0,5);
}

void generateCircle(int x, int y, int clickedTime, int maxSize, int startSize, int intervalSize){
 // check if the ellipse has reached its maximum size
 if(startSize < maxSize){
   // check if 100 milliseconds have passed, if they haven't
   // then throw the same vars back into the function
   if(millis() < clickedTime + 100){
     generateCircle(x, y, clickedTime, maxSize, startSize, intervalSize);
   }
   // if 100 ms have passed then draw an ellipse
   // of given size and then recall the function
   else{
     ellipse(x, y, startSize + intervalSize, startSize + intervalSize);
     int newSize = startSize + intervalSize;
     generateCircle(x, y, millis(), maxSize, newSize, intervalSize);
   }
 }
}

Thanks!

Thats excellent fjen, thankyou.

I understand the basic premise of what you've done with the code, which is to say, created an Ellipse class which has a function to draw the ellipse on the screen.  I understand why this achieves my goal better than my original idea.

I have a couple of questions, though.

First, do you know where I can find out more about the Vector array you create at the beginning of the code?  I cannot find it in the reference documentation.

Secondly, why is it that you are able to have two draw() functions in the code?  The processing reference is quite explicit that draw() can only exist once per sketch.

Thanks again.

Thanks fjen,
this is just what I needed!!!