private static List <SubsectorEdge> CreateSubsectorEdges(ConvexTraversal convexTraversal, Rotation rotation)
{
List <ConvexTraversalPoint> traversal = convexTraversal.Traversal;
Debug.Assert(traversal.Count >= 3, "Traversal must yield at least a triangle in size");
List <SubsectorEdge> subsectorEdges = new List <SubsectorEdge>();
ConvexTraversalPoint firstTraversal = traversal.First();
Vec2D startPoint = firstTraversal.Vertex;
foreach (ConvexTraversalPoint traversalPoint in traversal)
{
BspSegment segment = traversalPoint.Segment;
Vec2D endingPoint = segment.Opposite(traversalPoint.Endpoint).Struct();
bool traversedFrontSide = CheckIfTraversedFrontSide(traversalPoint, rotation);
SubsectorEdge edge = new SubsectorEdge(startPoint, endingPoint, segment.Line.Value, traversedFrontSide);
subsectorEdges.Add(edge);
Debug.Assert(startPoint != endingPoint, "Traversal produced the wrong endpoint indices");
startPoint = endingPoint;
}
Debug.Assert(subsectorEdges.Count == traversal.Count, "Added too many subsector edges in traversal");
return(subsectorEdges);
}
private static bool CheckIfTraversedFrontSide(ConvexTraversalPoint traversalPoint, Rotation rotation)
{
switch (rotation)
{
case Rotation.Left:
return(traversalPoint.Endpoint == Endpoint.End);
case Rotation.Right:
return(traversalPoint.Endpoint == Endpoint.Start);
default:
Debug.Assert(false, "Should never be handling a non-rotational traversal");
return(true);
}
}