[ARX程序]：请问如何填充一个圆环.

myocean

AcDbObjectId CKsjLayout::hatch( AcDbObjectIdArray eIds,
                                                    const char *pat , double factor,double angle)
{
        assertReadEnabled();
        AcDbHatch        *pHatch = new AcDbHatch();
        AcGeVector3d normal(0.0, 0.0, 1.0);
    pHatch->setNormal(normal);
    pHatch->setElevation(0.0);

    // Set hatch pattern to ANSI31 predefined type
    //
        pHatch->setPatternAngle(angle);
        pHatch->setPatternScale(factor);
    pHatch->setPattern(AcDbHatch::kPreDefined, pat);
        pHatch->setHatchStyle(AcDbHatch::kIgnore);
        pHatch->setAssociative(Adesk::kTrue);
        pHatch->appendLoop(AcDbHatch::kExternal, eIds);
        pHatch->evaluateHatch();
        pHatch->setLayer(m_layer);
        AcDbObjectId eId;
        eId = AddDb(pHatch);
        pHatch->close();
        return(eId);
}
应该设置里面的哪个参数呢?