bbox.x0 = min (_points[0].x, _points[1].x);
bbox.y0 = min (_points[0].y, _points[1].y);
bbox.x1 = max (_points[0].x, _points[1].x);
bbox.x0 = min (_points[0].x, _points[1].x);
bbox.y0 = min (_points[0].y, _points[1].y);
bbox.x1 = max (_points[0].x, _points[1].x);