public static IPolygon Union(List <IPolygon> polygons)
{
if (polygons.Count == 0)
{
return(null);
}
if (polygons.Count == 1)
{
return(polygons[0]);
}
/*
* if (polygons.Count > 100)
* {
* return polygons[0];
* }
*/
Clip_polygon union_polygon = new Clip_polygon();
Clip_polygon polygon1 = ClipWrapper.PolygonTo_Clip_polygon(polygons[0]);
try
{
for (int i = 1; i < polygons.Count; i++)
{
union_polygon = new Clip_polygon();
Clip_polygon polygon2 = ClipWrapper.PolygonTo_Clip_polygon(polygons[i]);
ClipPolygon(ref polygon1, ref polygon2, ClipOperation.Union, ref union_polygon);
if (i == 1)
{
ClipWrapper.Free_Clip_polygon(polygon1);
}
else
{
ClipWrapper.FreePolygon(ref polygon1);
}
ClipWrapper.Free_Clip_polygon(polygon2);
polygon1 = union_polygon;
}
IPolygon polygon = ClipWrapper.Clip_polygon_ToPolygon(union_polygon);
return(polygon);
}
finally
{
ClipWrapper.FreePolygon(ref union_polygon);
}
}
public static GeomTristrip PolygonToTristip(IPolygon polygon)
{
Clip_tristrip clip_strip = new Clip_tristrip();
Clip_polygon clip_pol = ClipWrapper.PolygonTo_Clip_polygon(polygon);
try
{
Polygon2Tristrip(ref clip_pol, ref clip_strip);
GeomTristrip tristrip = ClipWrapper.Clip_strip_ToTristrip(clip_strip);
return(tristrip);
}
finally
{
ClipWrapper.Free_Clip_polygon(clip_pol);
ClipWrapper.FreeTristrip(ref clip_strip);
}
}
public static IPolygon Clip(ClipOperation operation, IPolygon subject_polygon, IPolygon clip_polygon)
{
Clip_polygon Clip_polygon = new Clip_polygon();
Clip_polygon Clip_subject_polygon = ClipWrapper.PolygonTo_Clip_polygon(subject_polygon);
Clip_polygon Clip_clip_polygon = ClipWrapper.PolygonTo_Clip_polygon(clip_polygon);
try
{
ClipPolygon(ref Clip_subject_polygon, ref Clip_clip_polygon, operation, ref Clip_polygon);
IPolygon polygon = ClipWrapper.Clip_polygon_ToPolygon(Clip_polygon);
return(polygon);
}
finally
{
ClipWrapper.Free_Clip_polygon(Clip_subject_polygon);
ClipWrapper.Free_Clip_polygon(Clip_clip_polygon);
ClipWrapper.FreePolygon(ref Clip_polygon);
}
}
