这是OpenCV的drawMatches()功能:voiddrawMatches(Matimg1,vectorkeypoints1,Matimg2,vectorkeypoints2,vectormatches,MatoutImg)//wantkeypoints1[i]=keypoints2[matches[i]]注意matches类型为vector.这是DMatch构造函数:DMatch(intqueryIdx,inttrainIdx,floatdistance)据推测,queryIdx是一组关键点的索引,trainIdx是另一组关键点的索引。问题:queryIdx是真的吗?索引到ke