Qt中求两线段交点

QPointF MapEditor::getIntersectPos(QPointF posA, QPointF posB, QPointF posC, QPointF posD)//返回AB与CD交点，无交点返回（0,0）
{
QLineF line1(posA, posB);
QLineF line2(posC, posD);
QPointF interPos(0,0);
QLineF::IntersectType type = line1.intersect(line2, &interPos);
if (type != QLineF::BoundedIntersection)
interPos = QPointF(0, 0);
return interPos;
}