AcdbHatch setPatternScale no effect

[Anonymous]

the following code can modify the patterscale of an existing hatch, but the hatch dosen't change its outlook. why?

  AcDbObjectId idHatch;
    if (!Acad_Selection::SelEnt(idHatch,_T("Hatch")))
    {
        return;
    }

    AcDbObjectPointer<AcDbHatch> pHatch(idHatch,AcDb::kForWrite);
    if (Acad::eOk != pHatch.openStatus())
    {
        return;
    }
    static int nTemp = 1;
    Acad::ErrorStatus es = pHatch->setPatternScale(pHatch->patternScale()*(nTemp%2 == 0?2:0.5));
    es = pHatch->evaluateHatch();
    ++nTemp;

[Alexander.Rivilis]

---

    es = pHatch->evaluateHatch();

---

What es value?

[Anonymous]

it is weird that both return eOK. 

[Alexander.Rivilis · Accepted solution]

static void HatchScaleHalf(void)
{
    ads_name en; ads_point p;
    if (acedEntSel(_T("\nSelect Hatch: "),en,p) == RTNORM) {
        AcDbObjectId eid; acdbGetObjectId(eid,en);
        AcDbObjectPointer<AcDbHatch> pHatch(eid,AcDb::kForWrite);
        Acad::ErrorStatus es = pHatch.openStatus();
        if (es == Acad::eOk) {
            pHatch->setPatternScale(pHatch->patternScale()*0.5);
            pHatch->setPattern(pHatch->patternType(),pHatch->patternName());
            pHatch->evaluateHatch();
        } else if (es == Acad::eNotThatKindOfClass) {
            acutPrintf(_T("\nIt is not hatch!"));
        }
    }
}

[Anonymous]

well, it woks any way, but still confuses me.  still thanks much.