/// <summary>
/// Exhaustive search to update neighbor pointers
/// </summary>
/// <param name="t"></param>
public void MarkNeighbor(Triangle t)
{
if (t.Contains(Points[1], Points[2]))
{
_neighbours[0] = t;
t.MarkNeighbor(Points[1], Points[2], this);
}
else if (t.Contains(Points[0], Points[2]))
{
_neighbours[1] = t;
t.MarkNeighbor(Points[0], Points[2], this);
}
else if (t.Contains(Points[0], Points[1]))
{
_neighbours[2] = t;
t.MarkNeighbor(Points[0], Points[1], this);
}
}
private void EdgeEvent(SweepContext tcx, TriPoint ep, TriPoint eq, Triangle triangle, TriPoint point)
{
if (IsEdgeSideOfTriangle(triangle, ep, eq))
{
return;
}
TriPoint p1 = triangle.PointCCW(point);
Winding o1 = TriUtil.Orient2d(eq, p1, ep);
if (o1 == Winding.Collinear)
{
if (triangle.Contains(eq, p1))
{
triangle.MarkConstrainedEdge(eq, p1);
// We are modifying the constraint maybe it would be better to
// not change the given constraint and just keep a variable for the new constraint
tcx.EdgeEvent.ConstrainedEdge.Q = p1;
triangle = triangle.NeighborAcross(point);
EdgeEvent(tcx, ep, p1, triangle, p1);
}
else
{
throw new NotSupportedException("EdgeEvent - collinear points not supported");
}
return;
}
TriPoint p2 = triangle.PointCW(point);
Winding o2 = TriUtil.Orient2d(eq, p2, ep);
if (o2 == Winding.Collinear)
{
if (triangle.Contains(eq, p2))
{
triangle.MarkConstrainedEdge(eq, p2);
// We are modifying the constraint maybe it would be better to
// not change the given constraint and just keep a variable for the new constraint
tcx.EdgeEvent.ConstrainedEdge.Q = p2;
triangle = triangle.NeighborAcross(point);
EdgeEvent(tcx, ep, p2, triangle, p2);
}
else
{
throw new NotSupportedException("EdgeEvent - collinear points not supported");
}
return;
}
if (o1 == o2)
{
// Need to decide if we are rotating CW or CCW to get to a triangle
// that will cross edge
if (o1 == Winding.CW)
{
triangle = triangle.NeighborCCW(point);
}
else
{
triangle = triangle.NeighborCW(point);
}
EdgeEvent(tcx, ep, eq, triangle, point);
}
else
{
// This triangle crosses constraint so lets flippin start!
FlipEdgeEvent(tcx, ep, eq, triangle, point);
}
}