Hello,
I tried to use % in an attempt to constrain x and y inside the window. This did not turn out very well, mostly because mod in Processing includes the sign in the remainder. That is, when my x value goes negative, the modulo operation does not return a positive remainder, thus kept it inside my window. I ended up using the modified if-else version with the use of a couple of conditionals. I thought the use of % would work well for constraing, but now I find this not to be true. Or am I wrong on this?

Here is my code (not working):
Code:

x = x % width; // I also tried translating, and scaling, and though I believe there must be a way to do it using modolus, I could not figure it out this time ...
 

... but this one works as intended ...
Code:

x = (x<minX) ? maxX : (x>maxX) ? minX : x;
 

Are there other ways, better ways, to do this?

Here is the complete working program in case anyone was wondering:
Code:

float x, y;
int maxX, maxY, minX, minY;
float rot, rotNoise;

void setup(){
  size (300,300);
  minX = 50;
  maxX = 250;
  minY = 50;
  maxY = 250;
  x = 150;
  y = 150;
  rot = random(TWO_PI);
//  noiseSeed(10);
}

void draw(){
//translate(150, 150);
  //  background(120,90,90);
  rotNoise = noise(rot);
 // println("rotNoise = "+rotNoise);
  

  x+=cos(rotNoise*TWO_PI);
  y+=sin(rotNoise*TWO_PI);
  
    y = (y<minY) ? maxY : (y>maxY) ? minY : y;
  x = (x<minX) ? maxX : (x>maxX) ? minX : x;

  line(x,y, x+2, y+2);

  rot += TWO_PI/1300;

}
 

Thanks! Your solution Code:

x = (x + width) % width; 

is doing exactly what I was after in the first place.

I am not sure I understand your comment about my ?: solution, though, as it seems to work perfect for its purpose. Ah, but now I understand what you are saying! I didn't quite get the 'on' until now ... Anyways, I'm not sure if that is a problem at all ... where else should it be? I guess if we are talking about making patterns and such, the modularity would be of importance, and thus it should be taken care of properly, but in this case, where I am only concerned with keeping a moving 'thing' inside a boundary, it is actually better, imo. Thanks for your feedback!