关于自定义对象捕捉模式方面问题

xubufeich

请问:AcdbCustomOSnapInfo类中 getOsnapInfo(
AcDbEntity* pickedObject,
int gsSelectionMark,
const AcGePoint3d& pickPoint,
const AcGePoint3d& lastPoint,
const AcGeMatrix3d& viewXform,
AcArray<AcGePoint3d>& snapPoints,
AcArray<int>& geomIdsForPts,
AcArray<AcGeCurve3d*>& snapCurves,
AcArray<int>& geomIdsForLines)中,snapCurves参数为什么只能支持AcGeLine3d而不支持其他的曲线类呢?譬如:AcDbCirArc3d?