[讨论]：大家讨论一下从AcDbLine派生时需要重载哪些函数?

qianxihun

可以派生出来的,但好象有些函数不能用,比如TRIM  EXTEND等,请大家讨论一下还有哪些函数需要重载?
以下是代码:
#include "aced.h"
#include "adslib.h"
#include "dbsymtb.h"
#include "acgi.h"
#include "dbapserv.h"
#include "dbents.h"

class myline: public AcDbLine
{
public:
    ACRX_DECLARE_MEMBERS(myline);
     myline();
    ~myline();
};

ACRX_DXF_DEFINE_MEMBERS(myline,AcDbEntity,
AcDb::kDHL_CURRENT, AcDb::kMReleaseCurrent, 0x5,\
    myline,myline);

myline::myline()
{
}
myline::~myline()
{
}

void
addmyline()
{
        ads_point pt1,pt2;
        if ((ads_getpoint(NULL,"\nStart point:",pt1))!=RTNORM)
       return;
    if ((ads_getpoint(pt1,"\nEnd point:",pt2))!=RTNORM)
           return;

    AcGePoint3d  pt11,pt21;
        pt11.set(pt1[X],pt1[Y],pt1[Z]);
        pt21.set(pt2[X],pt2[Y],pt2[Z]);

    myline *pNewObj = new myline;
        pNewObj->setStartPoint(pt11);
        pNewObj->setEndPoint(pt21);

    AcDbBlockTable *pBlockTable;
    acdbHostApplicationServices()->workingDatabase()
        ->getSymbolTable(pBlockTable, AcDb::kForRead);

    AcDbBlockTableRecord *pBlock;
    pBlockTable->getAt(ACDB_MODEL_SPACE, pBlock,
        AcDb::kForWrite);

    AcDbObjectId objId;
    pBlock->appendAcDbEntity(objId, pNewObj);

    pBlockTable->close();
    pBlock->close();
    pNewObj->close();
}


void
initapp()
{
    myline::rxInit();
    acrxBuildClassHierarchy();

    acedRegCmds->addCommand("qx",
                            "qq",
                            "qq",
                            ACRX_CMD_TRANSPARENT,
                            addmyline);
}


extern "C" AcRx::AppRetCode
acrxEntryPoint(AcRx::AppMsgCode msg, void* appId)
{
    switch (msg) {
    case AcRx::kInitAppMsg:
                acrxDynamicLinker->unlockApplication(appId);
                acrxDynamicLinker->registerAppMDIAware(appId);
        initapp();
        break;
    case AcRx::kUnloadAppMsg:
        acedRegCmds->removeGroup("qx");
        deleteAcRxClass(myline::desc());
    }
    return AcRx::kRetOK;
}