private IntersectionResults BuildFinalResults(Polygon2 intersectedPolygon) {
Contract.Requires(intersectedPolygon != null);
Contract.Ensures(Contract.Result<IntersectionResults>() != null);
Contract.Ensures(intersectedPolygon.Count >= Contract.OldValue(intersectedPolygon).Count);
if (intersectedPolygon.Count == 0) {
var untouchedA = FindUntouchedRingsA();
var untouchedB = FindUntouchedRingsB();
intersectedPolygon.AddRange(QualifyRings(untouchedA, untouchedB, true));
intersectedPolygon.AddRange(QualifyRings(untouchedB, untouchedA, false));
}
else {
var intersectedResultTree = new RingBoundaryTree(intersectedPolygon);
intersectedPolygon.AddRange(
FilterQualifiedRingsToBoundaryTree(
QualifyRings(FindUntouchedRingsA(), B, true),
intersectedResultTree
)
);
intersectedPolygon.AddRange(
FilterQualifiedRingsToBoundaryTree(
QualifyRings(FindUntouchedRingsB(), A, false),
intersectedResultTree
)
);
}
return new IntersectionResults {
Polygon = intersectedPolygon
};
}
private static List<Ring2> QualifyRings(
Polygon2 untouchedRings,
Polygon2 polygon,
bool qualifyEqual
) {
Contract.Requires(untouchedRings != null);
Contract.Requires(polygon != null);
Contract.Ensures(Contract.Result<List<Ring2>>() != null);
Contract.Ensures(Contract.ForAll(Contract.Result<List<Ring2>>(), x => null != x));
var result = new List<Ring2>();
var ringTree = new RingBoundaryTree(polygon);
foreach (var ring in untouchedRings) {
Contract.Assume(ring != null);
// TODO: speed this up through some kind of magic, like RingBoundaryTree or something
// TODO: var eq = new SpatialEqualityComparerThing(ringA); var stuff = otherRings.Where(r = > eq.SpatiallyEqual(r));
if (polygon.Any(r => ring.SpatiallyEqual(r))) {
if (qualifyEqual)
result.Add(ring.Clone());
}
else if (ringTree.NonIntersectingContains(ring))
result.Add(ring.Clone());
}
Contract.Assume(Contract.ForAll(result, x => null != x));
return result;
}
private static IEnumerable<Ring2> FilterQualifiedRingsToBoundaryTree(List<Ring2> rings, RingBoundaryTree boundaryTree) {
Contract.Requires(rings != null);
Contract.Requires(boundaryTree != null);
Contract.Ensures(Contract.Result<IEnumerable<Ring2>>() != null);
Contract.Ensures(Contract.ForAll(Contract.Result<IEnumerable<Ring2>>(), x => x != null));
return rings.Where(ring => ring.Hole.GetValueOrDefault() == boundaryTree.NonIntersectingContains(ring));
}
