private static List<EdgeAggregator> CheckAndGenerateParallelImplyAlternateInterior(Intersection inter1, Intersection inter2, Parallel parallel)
{
List<EdgeAggregator> newGrounded = new List<EdgeAggregator>();
// The two intersections should not be at the same vertex
if (inter1.intersect.Equals(inter2.intersect)) return newGrounded;
// Determine the transversal
Segment transversal = inter1.AcquireTransversal(inter2);
if (transversal == null) return newGrounded;
//
// Ensure the non-traversal segments align with the parallel segments
//
Segment parallel1 = inter1.OtherSegment(transversal);
Segment parallel2 = inter2.OtherSegment(transversal);
// The non-transversals should not be the same (coinciding)
if (parallel1.IsCollinearWith(parallel2)) return newGrounded;
Segment coincidingParallel1 = parallel.CoincidesWith(parallel1);
Segment coincidingParallel2 = parallel.CoincidesWith(parallel2);
// The pair of non-transversals needs to align exactly with the parallel pair of segments
if (coincidingParallel1 == null || coincidingParallel2 == null) return newGrounded;
// Both intersections should not be referring to an intersection point on the same parallel segment
if (parallel.segment1.PointLiesOn(inter1.intersect) && parallel.segment1.PointLiesOn(inter2.intersect)) return newGrounded;
if (parallel.segment2.PointLiesOn(inter1.intersect) && parallel.segment2.PointLiesOn(inter2.intersect)) return newGrounded;
// The resultant candidate parallel segments shouldn't share any vertices
if (coincidingParallel1.SharedVertex(coincidingParallel2) != null) return newGrounded;
if (inter1.StandsOnEndpoint() && inter2.StandsOnEndpoint())
{
//
// Creates a basic S-Shape with standsOnEndpoints
//
// offThis ______
// |
// offThat ______|
//
// Return <offThis, offThat>
KeyValuePair<Point, Point> cShapePoints = inter1.CreatesBasicCShape(inter2);
if (cShapePoints.Key != null && cShapePoints.Value != null) return newGrounded;
//
// Creates a basic S-Shape with standsOnEndpoints
//
// ______ offThat _______
// | \
// offThis ______| _____\
//
// Return <offThis, offThat>
KeyValuePair<Point, Point> sShapePoints = inter1.CreatesBasicSShape(inter2);
if (sShapePoints.Key != null && sShapePoints.Value != null)
{
return GenerateSimpleS(parallel, inter1, sShapePoints.Key, inter2, sShapePoints.Value);
}
return newGrounded;
}
// _______/________
// /
// /
// ______/_______
// /
if (inter1.Crossing() && inter2.Crossing()) return GenerateDualCrossings(parallel, inter1, inter2);
// No alt int in this case:
// Creates an F-Shape
// top
// _____ offEnd <--- Stands on Endpt
// |
// |_____ offStands <--- Stands on
// |
// |
// bottom
KeyValuePair<Point, Point> fShapePoints = inter1.CreatesFShape(inter2);
if (fShapePoints.Key != null && fShapePoints.Value != null) return newGrounded;
// Alt. Int if an H-Shape
//
// | |
// |_____|
// | |
// | |
//
if (inter1.CreatesHShape(inter2)) return GenerateH(parallel, inter1, inter2);
// Creates an S-Shape
//
// |______
// |
// ______|
// |
//
// Order of non-collinear points is order of intersections: <this, that>
KeyValuePair<Point, Point> standardSShapePoints = inter1.CreatesStandardSShape(inter2);
if (standardSShapePoints.Key != null && standardSShapePoints.Value != null)
{
return GenerateSimpleS(parallel, inter1, standardSShapePoints.Key, inter2, standardSShapePoints.Value);
}
// Corresponding if a flying-Shape
//
// | |
// |_____|___ offCross
// | |
// | |
//
Point offCross = inter1.CreatesFlyingShapeWithCrossing(inter2);
if (offCross != null)
{
return GenerateFlying(parallel, inter1, inter2, offCross);
}
//
// Creates a shape like an extended t
// offCross offCross
// | |
// _____|____ ______|______
// | |
// |_____ offStands offStands _____|
//
// Returns <offStands, offCross>
KeyValuePair<Point, Point> tShapePoints = inter1.CreatesCrossedTShape(inter2);
if (tShapePoints.Key != null && tShapePoints.Value != null)
{
return GenerateCrossedT(parallel, inter1, inter2, tShapePoints.Key, tShapePoints.Value);
}
//
// Creates a Topped F-Shape
// top
// offLeft __________ offEnd <--- Stands on
// |
// |_____ off <--- Stands on
// |
// |
// bottom
//
// Returns: <bottom, off>
KeyValuePair<Intersection, Point> toppedFShapePoints = inter1.CreatesToppedFShape(inter2);
if (toppedFShapePoints.Key != null && toppedFShapePoints.Value != null)
{
return GenerateToppedFShape(parallel, inter1, inter2, toppedFShapePoints.Key, toppedFShapePoints.Value);
}
return newGrounded;
}