/// <summary>
/// The core algorithm for bounding box tree intersection.<br/>
/// Supporting both lazy and pre-computed bounding box trees via the <see cref="IBoundingBoxTree{CurveParameter}"/> interface.
/// </summary>
/// <param name="bbt1">The first Bounding box tree object.</param>
/// <param name="tolerance">Tolerance as per default set as 1e-9.</param>
/// <returns>A collection of tuples extracted from the Yield method of the BoundingBoxTree.</returns>
internal static List <Tuple <T1, T1> > BoundingBoxTreeIntersection <T1>(IBoundingBoxTree <T1> bbt1,
double tolerance = 1e-9)
{
List <IBoundingBoxTree <T1> > aTrees = new List <IBoundingBoxTree <T1> >();
List <IBoundingBoxTree <T1> > bTrees = new List <IBoundingBoxTree <T1> >();
Tuple <IBoundingBoxTree <T1>, IBoundingBoxTree <T1> > firstSplit = bbt1.Split();
aTrees.Add(firstSplit.Item1);
bTrees.Add(firstSplit.Item2);
return(GetRoot(aTrees, bTrees, tolerance));
}
/// <summary>
/// The core algorithm to find the bounding box trees intersecting with a plane.<br/>
/// Supporting both lazy and pre-computed bounding box trees via the <see cref="IBoundingBoxTree{CurveParameter}"/> interface.
/// </summary>
/// <param name="bbt">The bounding box object.</param>
/// <param name="pl">The plane to intersect with.</param>
/// <param name="tolerance">Tolerance as per default set as 1e-9.</param>
/// <returns>A collection of extracted object from the Yield method of the BoundingBoxTree.</returns>
internal static List <T> BoundingBoxPlaneIntersection <T>(IBoundingBoxTree <T> bbt, Plane pl, double tolerance = 1e-9)
{
List <IBoundingBoxTree <T> > aTrees = new List <IBoundingBoxTree <T> > {
bbt
};
List <T> result = new List <T>();
while (aTrees.Count > 0)
{
IBoundingBoxTree <T> a = aTrees[aTrees.Count - 1];
aTrees.RemoveAt(aTrees.Count - 1);
if (a.IsEmpty())
{
continue;
}
Tuple <IBoundingBoxTree <T>, IBoundingBoxTree <T> > aSplit = a.Split();
var pt1 = a.BoundingBox().Max;
var pt2 = a.BoundingBox().Min;
_ = pl.ClosestPoint(pt1, out double h1);
_ = pl.ClosestPoint(pt2, out double h2);
if (Math.Abs(h1) < tolerance || Math.Abs(h2) < tolerance || h1 * h2 > 0.0)
{
if (a.IsIndivisible(tolerance))
{
continue;
}
aTrees.Add(aSplit.Item1);
aTrees.Add(aSplit.Item2);
}
else
{
if (a.IsIndivisible(tolerance))
{
result.Add(a.Yield());
continue;
}
aTrees.Add(aSplit.Item1);
aTrees.Add(aSplit.Item2);
}
}
return(result);
}
/// <summary>
/// The core algorithm for bounding box tree intersection.<br/>
/// Supporting both lazy and pre-computed bounding box trees via the <see cref="IBoundingBoxTree{CurveParameter}"/> interface.
/// </summary>
/// <param name="aTrees">The first Bounding box tree object.</param>
/// <param name="bTrees">The second Bounding box tree object.</param>
/// <param name="tolerance">Tolerance as per default set as 1e-9.</param>
/// <returns>A collection of tuples extracted from the Yield method of the BoundingBoxTree.</returns>
private static List <Tuple <T1, T2> > GetRoot <T1, T2>(List <IBoundingBoxTree <T1> > aTrees, List <IBoundingBoxTree <T2> > bTrees, double tolerance)
{
List <Tuple <T1, T2> > result = new List <Tuple <T1, T2> >();
while (aTrees.Count > 0)
{
IBoundingBoxTree <T1> a = aTrees[aTrees.Count - 1];
aTrees.RemoveAt(aTrees.Count - 1);
IBoundingBoxTree <T2> b = bTrees[bTrees.Count - 1];
bTrees.RemoveAt(bTrees.Count - 1);
if (a.IsEmpty() || b.IsEmpty())
{
continue;
}
if (BoundingBox.AreOverlapping(a.BoundingBox(), b.BoundingBox(), tolerance) == false)
{
continue;
}
bool aIndivisible = a.IsIndivisible(tolerance);
bool bIndivisible = b.IsIndivisible(tolerance);
Tuple <IBoundingBoxTree <T1>, IBoundingBoxTree <T1> > aSplit = a.Split();
Tuple <IBoundingBoxTree <T2>, IBoundingBoxTree <T2> > bSplit = b.Split();
if (aIndivisible && bIndivisible)
{
result.Add(new Tuple <T1, T2>(a.Yield(), b.Yield()));
continue;
}
if (aIndivisible)
{
aTrees.Add(a);
bTrees.Add(bSplit.Item2);
aTrees.Add(a);
bTrees.Add(bSplit.Item1);
continue;
}
if (bIndivisible)
{
aTrees.Add(aSplit.Item2);
bTrees.Add(b);
aTrees.Add(aSplit.Item1);
bTrees.Add(b);
continue;
}
aTrees.Add(aSplit.Item2);
bTrees.Add(bSplit.Item2);
aTrees.Add(aSplit.Item2);
bTrees.Add(bSplit.Item1);
aTrees.Add(aSplit.Item1);
bTrees.Add(bSplit.Item2);
aTrees.Add(aSplit.Item1);
bTrees.Add(bSplit.Item1);
}
return(result);
}