图块] AcDbBlockReference::explode 失败

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cDbBlockReference::explode fails

问题：

Why does AcDbBlockReference::explode produce incorrect results if there are
AcDbText or AcDbAttribute definition entities in the block that is exploded?

解答：

This isa known problem that is desribed in DevNote #TS36113.
AcDbBlockReference::explode internally calls AcDbText::getTransformedCopy that
produces incorrect results. The code below uses the code in DevNote #TS36113 to
explode an AcDbBlockReference correctly.

普通浏览复制代码
Acad::ErrorStatus safeExplode(const AcDbBlockReference* pRef,AcDbVoidPtrArray&entitySet)
{  
AcDbBlockTableRecord* pBTR;
Acad::ErrorStatus es;  
if ((es = acdbOpenAcDbObject((AcDbObject*&)pBTR, pRef->blockTableRecord(), AcDb::kForRead)) == Acad::eOk)
{   
  AcDbBlockTableRecordIterator* pIterator;
  if (pBTR->newIterator(pIterator) == Acad::eOk)
  {  
   AcGeMatrix3d xform = pRef->blockTransform();   
   AcGePoint3d pt3dBlkOrigin = pBTR->origin();  
   if (pt3dBlkOrigin != AcGePoint3d::kOrigin)
   {     
    AcGeVector3d xformOrigin = xform.translation();
    AcGeVector3d vectorOrigin(pt3dBlkOrigin.x,pt3dBlkOrigin.y,0.0);  
    vectorOrigin.transformBy(xform);
    xformOrigin -= vectorOrigin;   
    xform.setTranslation(xformOrigin);   
   }   
   pIterator->start();   
   while (!pIterator->done())
   {     
    AcDbEntity* pEntity;
    if (pIterator->getEntity(pEntity, AcDb::kForRead) == Acad::eOk)
    {
      // If pEntity does not implement getTransformedCopy()  
      // or explode() methods, we should simply ignore
      // that entity and continue to step into next entity
      // instead of exit prematurely. Most operations such
      // as BHATCH depends on complete iteration through  
      // the entire block entities.      
      AcDbEntity* pNewEntity;
      AcDbText* pText =NULL;   
      if (pText=AcDbText::cast(pEntity))  
       es = AdskUtil::safeGetTransformedCopy(pText,xform, pNewEntity);      
      else
      es = pEntity->getTransformedCopy(xform, pNewEntity);
      if (es==Acad::eOk)
      {
      entitySet.append(pNewEntity);
      }
      else if (Acad::eExplodeBeforeTransform == es)
      {
      AcDbVoidPtrArray explSet;  
      if (Acad::eOk == pEntity->explode(explSet))
      {
       for (int i = 0; i < explSet.length(); i++)
       {         
        AcDbEntity* pObj = (AcDbEntity*)explSet<i>;
        if (Acad::eOk == pObj->getTransformedCopy( xform, pNewEntity))
        {     
         entitySet.append(pNewEntity);   
        }        
        delete pObj;     
       }  
      }  
     }
     else if (Acad::eCopyFailed == es)
     {            
      AcDbVoidPtrArray explSet;   
      if (Acad::eOk == pEntity->explode(explSet))
      {            
       for (int i = 0; i < explSet.length(); i++)     
       {           
        AcDbEntity* pObj = (AcDbEntity*)explSet<i>;
        if (Acad::eOk == pObj->transformBy(xform))
        {         
         entitySet.append(pObj);
        }         
       }   
      }     
     }     
     pEntity->close();
    }  
    pIterator->step();
   }   
   delete pIterator;
  }  
  pBTR->close();
}
return es;
}