/// <summary>
/// Search in the BVH tree using a flexible "locator" object, which should return the
/// "distance" of a BVH Node object. Returns a list of results in increasing distance
/// up to a relative bound and absolute maximum.
/// </summary>
/// <param name="distance_max">The maximum distance to look for.</param>
/// <param name="relative_bound">Stop returning more items after 'relative_bound' times
/// the first item's distance.</param>
/// <param name="locator">A delegate, like Locate() but passed also the current 'distance_max'.</param>
/// <returns>A list of instances of the concrete BVHNodeBase subclass.</returns>
public List <BVHNodeBase> LocateList(float distance_max, float relative_bound, DistanceToNodeEx locator)
{
var output_list = new List <BVHNodeBase>();
if (!(root is BVHNode))
{
if (root != null)
{
float distance = locator(root, distance_max);
if (distance < distance_max)
{
output_list.Add(root);
}
}
return(output_list);
}
var heapq = new HeapQ <LocNext>();
BVHNodeBase base_node = root;
float distance_1 = 0;
while (distance_1 < distance_max)
{
if (base_node is BVHNode)
{
var node = (BVHNode)base_node;
float d_left = locator(node.left, distance_max);
if (d_left < distance_max)
{
if (!(node.left is BVHNode))
{
distance_max = Mathf.Min(distance_max, d_left * relative_bound);
}
heapq.Push(new LocNext(d_left, node.left));
}
float d_right = locator(node.right, distance_max);
if (d_right < distance_max)
{
if (!(node.right is BVHNode))
{
distance_max = Mathf.Min(distance_max, d_right * relative_bound);
}
heapq.Push(new LocNext(d_right, node.right));
}
}
else
{
output_list.Add(base_node);
}
if (heapq.Empty)
{
break;
}
LocNext next = heapq.Pop();
distance_1 = next.distance;
base_node = next.node;
}
return(output_list);
}
/// <summary>
/// Search in the BVH tree using a flexible "locator" delegate, which should return the
/// "distance" of a BVH Node object.
/// </summary>
/// <param name="distance">The maximum distance to look for.</param>
/// <param name="locator">A delegate. A typical implementation has got two cases: if
/// given an instance of a concrete class that the caller knows about, it should return
/// the distance to that; otherwise, it should return the distance to the bounding box.
/// The present algorithm assumes that when a bounding box grows, the distance returned
/// by "locator" decreases or stays constant.</param>
/// <returns>A instance of the concrete BVHNodeBase subclass.</returns>
public BVHNodeBase Locate(float distance_max, DistanceToNode locator)
{
if (!(root is BVHNode))
{
if (root != null)
{
float distance = locator(root, distance_max);
if (distance < distance_max)
{
return(root);
}
}
return(null);
}
var heapq = new HeapQ <LocNext>();
BVHNodeBase base_node = root;
while (true)
{
if (base_node is BVHNode)
{
var node = (BVHNode)base_node;
float d_left = locator(node.left, distance_max);
if (d_left < distance_max)
{
if (!(node.left is BVHNode))
{
distance_max = d_left;
}
heapq.Push(new LocNext(d_left, node.left));
}
float d_right = locator(node.right, distance_max);
if (d_right < distance_max)
{
if (!(node.right is BVHNode))
{
distance_max = d_right;
}
heapq.Push(new LocNext(d_right, node.right));
}
}
else
{
return(base_node);
}
if (heapq.Empty)
{
break;
}
LocNext next = heapq.Pop();
base_node = next.node;
}
return(null);
}
