gistfile1.txt

int size = 30;
boolean change = true;

void setup() {
   size(500, 500);
   frameRate(60);
   textAlign(CENTER);
} 

void draw() {
   background(0);
   if (size > 30 && change) {
       textSize(size);
       size--;
   } else if (size <= 80) {
       textSize(size);
       size++; 
       change = false; 
   } else {
       change = true; 
   }
 
   text("Hello world", 250, 250); 
}