判断一个点是否在面域上（包括在面域的边上），都投影到XY平面上_acdbray setunitdir

bool isPointOnRegion(AcGePoint3d pt,AcDbObjectId regionId)
{
 Acad::ErrorStatus es;

 AcDbRegion* pRegion ;
 es = acdbOpenObject( pRegion, regionId, AcDb::kForRead );
 if( es ) return false;

 //创建射线，根据射线与面域边线相交的点数为奇数就说明点在面域上的理论
 AcDbRay* pRay = new AcDbRay ;
 pRay->setBasePoint( pt );
 pRay->setUnitDir( AcGeVector3d(1, 0, 0));

   AcGePlane  projPlane = AcGePlane(AcGePoint3d(0,0,0), AcGeVector3d(0,0,1));
 AcGePoint3dArray ptArray;
 es = pRegion->intersectWith( pRay, AcDb::kOnBothOperands,projPlane, ptArray,0,0 );//AcDb::kExtendArg
  pRegion->close();
  delete pRay;
  if(es )
 {
  return false;
 }

 int iNum = ptArray.length();

 if( (iNum%2 ) == 0 ) return false;
  

 return true;
}