Scaling a QPolygon or QPolygonF
问题 I need to scale a polygon. write the following Qt Code: QPolygonF qpf=QPolygonF(QPolygon(4,points)); QTransform trans; trans=trans.scale(1.5,1.5); QPolygonF qpf2=trans.map(qpf); path.addPolygon(qpf2); for the points: Qt Code: static const int points[8] = { 10, 80, 20, 10, 80, 30, 90, 70 }; it generates ---15,120-- ---30,15-- ---120,45-- ---135,105-- thus it moves slightly too. is there a way to scale from center? for example origin of the shape should be the same point after scaling. is there