docs: public boolean checkFlip( SquareGrid grid ) {
  		if( grid.columns == 1 || grid.rows == 1 )
  			return false;
  
  		Point2D_F64 a = grid.get(0,0).center;
  		Point2D_F64 b = grid.get(0,grid.columns-1).center;
  		Point2D_F64 c = grid.get(grid.rows-1,0).center;
  
  		double x0 = b.x-a.x;
  		double y0 = b.y-a.y;
  
  		double x1 = c.x-a.x;
  		double y1 = c.y-a.y;
  
  		double z = x0 * y1 - y0 * x1;
  
  		return z < 0;
  	}