private (double xVel, double yVel) Avoid(Boid boid, double distance, double power)
        {
            // point away as boids get close
            var neighbors = Boids.Where(x => x.GetDistance(boid) < distance);

            (double sumClosenessX, double sumClosenessY) = (0, 0);
            foreach (var neighbor in neighbors)
            {
                double closeness = distance - boid.GetDistance(neighbor);
                sumClosenessX += (boid.X - neighbor.X) * closeness;
                sumClosenessY += (boid.Y - neighbor.Y) * closeness;
            }
            return(sumClosenessX * power, sumClosenessY *power);
        }
 private (double xVel, double yVel) Predator(Boid boid, double distance, double power)
 {
     // point away as predators get close
     (double sumClosenessX, double sumClosenessY) = (0, 0);
     for (int i = 0; i < PredatorCount; i++)
     {
         Boid   predator     = Boids[i];
         double distanceAway = boid.GetDistance(predator);
         if (distanceAway < distance)
         {
             double closeness = distance - distanceAway;
             sumClosenessX += (boid.X - predator.X) * closeness;
             sumClosenessY += (boid.Y - predator.Y) * closeness;
         }
     }
     return(sumClosenessX * power, sumClosenessY *power);
 }