ncollide3d/partitioning/visitor.rs
1/// The status of the spatial partitioning structure traversal.
2pub enum VisitStatus {
3 /// The traversal should continue on the children of the currently visited nodes.
4 Continue,
5 /// The traversal should not be executed on the children of the currently visited nodes.
6 Stop,
7 /// The traversal should exit immediately.
8 ExitEarly,
9}
10
11/// Trait implemented by visitor called during the traversal of a spatial partitioning data structure.
12pub trait Visitor<T, BV> {
13 /// Execute an operation on the content of a node of the spatial partitioning structure.
14 ///
15 /// Returns whether the traversal should continue on the node's children, if it should not continue
16 /// on those children, or if the whole traversal should be exited early.
17 fn visit(&mut self, bv: &BV, data: Option<&T>) -> VisitStatus;
18}
19
20/// Trait implemented by visitor called during a simultaneous spatial partitioning data structure tarversal.
21pub trait SimultaneousVisitor<T, BV> {
22 /// Execute an operation on the content of two nodes, one from each structure.
23 ///
24 /// Returns whether the traversal should continue on the nodes children, if it should not continue
25 /// on those children, or if the whole traversal should be exited early.
26 fn visit(
27 &mut self,
28 left_bv: &BV,
29 left_data: Option<&T>,
30 right_bv: &BV,
31 right_data: Option<&T>,
32 ) -> VisitStatus;
33}
34
35/// The next action to be taken by a BVH traversal algorithm after having visited a node with some data.
36pub enum BestFirstVisitStatus<N, Res> {
37 /// The traversal continues recursively, associating the given cost to the visited node and some associated result.
38 Continue {
39 /// The cost associated to this node.
40 cost: N,
41 /// The result, if any, associated to this cost.
42 result: Option<Res>,
43 },
44 /// The traversal does not continue recursively on the visited node's children.
45 Stop,
46 /// The traversal aborts.
47 ///
48 /// If a data is provided, then it is returned as the result of the traversal.
49 /// If no result is provided, then the last best result found becomes the result of the traversal.
50 ExitEarly(Option<Res>),
51}
52
53/// Trait implemented by cost functions used by the best-first search on a `BVT`.
54pub trait BestFirstVisitor<N, T, BV> {
55 /// The result of a best-first traversal.
56 type Result;
57
58 /// Compute the next action to be taken by the best-first-search after visiting a node containing the given bounding volume.
59 fn visit(
60 &mut self,
61 best_cost_so_far: N,
62 bv: &BV,
63 value: Option<&T>,
64 ) -> BestFirstVisitStatus<N, Self::Result>;
65}