tess::PathScratch Class Reference

#include <tess/path/path.h>

Classes
struct	OpenNode

Public Member Functions
void	reserve_nodes (std::size_t node_count)
void	clear () noexcept
auto	capacity_nodes () const noexcept -> std::size_t

Friends
template<typename World, typename Tag>
auto	astar_path (const World &world, PathRequest request, PathScratch &scratch, MissingChunkPolicy policy=MissingChunkPolicy::ReportIndeterminate) -> PathResult
template<typename World, typename Tag, typename Provider>
auto	astar_path (const World &world, PathRequest request, PathScratch &scratch, MissingChunkPolicy policy, const Provider &provider) -> PathResult
	Finds a minimum-step path composed with a special-transition provider.
template<typename World, typename Class>
auto	weighted_astar_path (const World &world, PathRequest request, PathScratch &scratch, MissingChunkPolicy policy=MissingChunkPolicy::ReportIndeterminate) -> PathResult
template<typename World, typename Class, typename Provider>
auto	weighted_astar_path (const World &world, PathRequest request, PathScratch &scratch, MissingChunkPolicy policy, const Provider &provider) -> PathResult
	Finds a weighted path composed with a special-transition provider.
template<typename World, typename Class, typename Provider>
auto	weighted_astar_path (const World &world, PathRequest request, PathScratch &scratch, MissingChunkPolicy policy, const Provider &provider, PathTieBreak tie_break) -> PathResult
	Finds a provider-aware weighted path with seeded equal-cost tie-breaking.
template<typename World, typename Class>
auto	weighted_astar_path (const World &world, PathRequest request, PathScratch &scratch, PathTieBreak tie_break, MissingChunkPolicy policy=MissingChunkPolicy::ReportIndeterminate) -> PathResult
	Finds an optimal weighted path with seeded equal-cost tie-breaking.
template<typename World, typename Tag>
auto	cached_astar_path (const World &world, PathRequest request, PathScratch &scratch, UnitRouteCache &cache, MissingChunkPolicy policy=MissingChunkPolicy::ReportIndeterminate) -> PathResult
	Finds a cached empty-provider route or computes and stores one.
template<typename World, typename Tag, typename Provider>
auto	cached_astar_path (const World &world, PathRequest request, PathScratch &scratch, UnitRouteCache &cache, const Provider &provider, MissingChunkPolicy policy=MissingChunkPolicy::ReportIndeterminate) -> PathResult
	Runs unit A* with exact and same-goal suffix reuse from caller-owned cache.

Detailed Description

Owns reusable A* frontier, node state, and returned path storage.

Instances are caller-owned and require external synchronization. Reserving for the search space avoids allocation once warm.

Friends And Related Symbol Documentation

astar_path

template<typename World, typename Tag>

auto astar_path ( const World & world, PathRequest request, PathScratch & scratch, MissingChunkPolicy policy = MissingChunkPolicy::ReportIndeterminate ) -> PathResult

friend

Finds a minimum-step path using a truthy passability field.

The returned path borrows scratch until its next mutation. Invalid endpoints and exhausted searches are distinguished in PathStatus.

cached_astar_path

template<typename World, typename Tag>

auto cached_astar_path ( const World & world, PathRequest request, PathScratch & scratch, UnitRouteCache & cache, MissingChunkPolicy policy = MissingChunkPolicy::ReportIndeterminate ) -> PathResult

friend

Finds a cached empty-provider route or computes and stores one.

Contract: cached_astar_path never refreshes cache against the world by itself (the refresh scans world versions: O(chunk_count) on dense worlds, O(resident_count) on sparse ones – paid once per edit batch rather than per lookup). Direct adopters must therefore run cache.refresh_if_world_changed(world) at two points:

1. Once immediately after binding the cache to a world, BEFORE the first lookup. The first refresh only captures the baseline fingerprint in exact mode – with no baseline it cannot detect a change – so entries stored before that baseline survive an edit made before the first refresh, and a later hit can serve the pre-edit route.
2. After every world edit batch – including correctly version-marked edits (field write plus mark_content_changed) – before the next lookup. Otherwise a hit may return the pre-edit route (for example, straight through a tile the edit just closed).

PathRequestRuntime performs the refresh once per batch in prepare_process under the DEFAULT cache policy; a runtime caller that sets PathRuntimeCachePolicy::invalidate_unit_route_cache_on_world_change to false opts out of that and carries this obligation directly. The definition in route_cache.h carries the full staleness contract, including the exact-mode alternatives.

weighted_astar_path

template<typename World, typename Class>

auto weighted_astar_path ( const World & world, PathRequest request, PathScratch & scratch, MissingChunkPolicy policy = MissingChunkPolicy::ReportIndeterminate ) -> PathResult

friend

Finds a minimum-cost path for a compile-time movement class.

The returned path borrows scratch until its next mutation.

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The documentation for this class was generated from the following file:

• include/tess/path/path.h