Just curious if anyone out there knows a good way to constrain the "flock" model of boids to a user-defined rectangular area, such that they change vector when they hit the edge. Any help would be greatly appreciated.

I would say if he is working with vectors he probably got a velocity vector. so all he needs to do is to multiply it by -1... But thats more or less what you just said.

so it could look something like this :


void bounceOfEdge(){
   if (pos.x > width || pos.x < 0){ // if x pos is greater than right hand edge OR less than left hand edge
     vel.set(vel.x*-1,vel.y,0); // bounce off the edge by turning vel. negative
   }
   if (pos.y > height || pos.y < 0) { // if y pos is greater than bottom edge OR less than top edge
     vel.set(vel.x,vel.y*-1,0);
   }