エンベロープから楕円を作成

Dim pPoint As IPoint
Set pPoint = New Point
Call pPoint.PutCoords(422480, 324767.31)    '中心点

Dim pEnvelope As IEnvelope
Set pEnvelope = pPoint.Envelope

pEnvelope.XMin = pPoint.X - 5       '楕円の左端
pEnvelope.XMax = pPoint.X + 2       '楕円の右端
pEnvelope.YMin = pPoint.Y - 2       '楕円の上端
pEnvelope.YMax = pPoint.Y + 4       '楕円の下端

Dim pConstructEllipticArc As IConstructEllipticArc
Set pConstructEllipticArc = New EllipticArc
Call pConstructEllipticArc.ConstructEnvelope(pEnvelope)

Dim pSegmentCollection As ISegmentCollection
Set pSegmentCollection = New Polygon
Call pSegmentCollection.AddSegment(pConstructEllipticArc)