code: private void addPoints(int minX, int minY, int maxX, int maxY, Collidable collidable)
      {
          addPoint(new Point(minX, minY), collidable);
  
          if (minX != maxX && minY == maxY)
          {
              addPoint(new Point(maxX, minY), collidable);
          }
          else if (minX == maxX && minY != maxY)
          {
              addPoint(new Point(minX, maxY), collidable);
          }
          else if (minX != maxX)
          {
              addPoint(new Point(minX, maxY), collidable);
              addPoint(new Point(maxX, minY), collidable);
              addPoint(new Point(maxX, maxY), collidable);
          }
      }
docs: Add point and adjacent points depending of the collidable max collision size.
  
  @param minX The min horizontal location.
  @param minY The min vertical location.
  @param maxX The min horizontal location.
  @param maxY The min vertical location.
  @param collidable The collidable reference.