学步园

IEnvelope为IPolygon//by yl 2003.05.10

function EnvToPoly(pEnv: IEnvelope): IPolygon;

var

    pPointsColl                         : IPointCollection;

    P1, P2, p3, p4                      : IPoint;

    pTopo                               : ITopologicalOperator;

begin

    pPointsColl := CoPolygon.Create as IPointCollection;

    pEnv.Get_LowerLeft(P1);

    pEnv.Get_UpperLeft(P2);

    pEnv.Get_UpperRight(p3);

    pEnv.Get_LowerRight(p4);

    pPointsColl.AddPoints(1, P1);

    pPointsColl.AddPoints(1, P2);

    pPointsColl.AddPoints(1, p3);

    pPointsColl.AddPoints(1, p4);

    pTopo := pPointsColl as ITopologicalOperator;

    pTopo.Simplify();

    result := pPointsColl as IPolygon;

end;