[VBA函数]：如何判断两条直线是否有重合段？

ppengxm

如题，如何判断两条直线是否有重合段？

chxmhsd

判断两直线的交点数是否大于1；
注意AcDb::Intersect intType的选项

virtual Acad::ErrorStatus
intersectWith(
    const AcDbEntity* pEnt,
    AcDb::Intersect intType,
    AcGePoint3dArray& points,
    int thisGsMarker = 0,

    int otherGsMarker= 0) const;

pEnt        Input entity with which "this" entity is to intersect
intType        Input type of intersection requested
points        Output with the points of intersection appended
thisGsMarker        Input GS marker of subentity of "this" entity that's involved in the intersection operation. Use the 0 default if not applicable.
otherGsMarker        Input GS marker of subentity of the entity pointed to by pEnt that's involved in the intersection operation. Use the 0 default if not applicable.

Function usage
It finds the intersections of the entity pointed to by pEnt and all the edges of the bounding box of this entity.
The intType is used to determine how to deal with extending the two entities in order to calculate intersections. The possible AcDb::Intersect values are:

Value        Meaning
AcDb::kOnBothOperands        Do not extend either entity. This results in only calculating intersections where the two entitys' geometry actually intersect
AcDb::kExtendThis        Extend this entity (if necessary) when calculating intersections, but do not extend the pEnt entity.
AcDb::kExtendArg        Extend the pEnt entity (if necessary) when calculating intersections, but do not extend this entity.
AcDb::kExtendBoth        Extend both the pEnt entity and this entity (if necessary) when calculating intersections

wuweifan

Adesk::Boolean

isColinearTo(

const AcGeLinearEnt2d& line,

const AcGeTol& tol = AcGeContext::gTol) const;

上面函数就是计算两实体是否重合

fengyou

用AcGeLinearEnt2d::overlap Function 除能判断是否有重合段外，还能返回重合段实体。