mirror
/
OpenTTD
mirror of https://github.com/OpenTTD/OpenTTD
1
0
Fork 0
Code Issues

Codechange: migrate aystar to use YAPF's nodelist infrastructure

pull/12739/head
Rubidium 2024-05-12 14:04:35 +02:00 committed by rubidium42
parent 48539992e8
commit 0e75dfd49f
5 changed files with 64 additions and 229 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

49
src/landscape.cpp
View File

@ -1201,48 +1201,48 @@ struct River_UserData {
};
/* AyStar callback for checking whether we reached our destination. */
static int32_t River_EndNodeCheck(const AyStar *aystar, const OpenListNode *current)
static int32_t River_EndNodeCheck(const AyStar *aystar, const PathNode *current)
{
return current->path.node.tile == *(TileIndex*)aystar->user_target ? AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
return current->GetTile() == *(TileIndex*)aystar->user_target ? AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
}
/* AyStar callback for getting the cost of the current node. */
static int32_t River_CalculateG(AyStar *, AyStarNode *, OpenListNode *)
static int32_t River_CalculateG(AyStar *, AyStarNode *, PathNode *)
{
return 1 + RandomRange(_settings_game.game_creation.river_route_random);
}
/* AyStar callback for getting the estimated cost to the destination. */
static int32_t River_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *)
static int32_t River_CalculateH(AyStar *aystar, AyStarNode *current, PathNode *)
{
return DistanceManhattan(*(TileIndex*)aystar->user_target, current->tile);
return DistanceManhattan(*(TileIndex*)aystar->user_target, current->m_tile);
}
/* AyStar callback for getting the neighbouring nodes of the given node. */
static void River_GetNeighbours(AyStar *aystar, OpenListNode *current)
static void River_GetNeighbours(AyStar *aystar, PathNode *current)
{
TileIndex tile = current->path.node.tile;
TileIndex tile = current->GetTile();
aystar->num_neighbours = 0;
for (DiagDirection d = DIAGDIR_BEGIN; d < DIAGDIR_END; d++) {
TileIndex t2 = tile + TileOffsByDiagDir(d);
if (IsValidTile(t2) && FlowsDown(tile, t2)) {
aystar->neighbours[aystar->num_neighbours].tile = t2;
aystar->neighbours[aystar->num_neighbours].direction = INVALID_TRACKDIR;
aystar->neighbours[aystar->num_neighbours].m_tile = t2;
aystar->neighbours[aystar->num_neighbours].m_td = INVALID_TRACKDIR;
aystar->num_neighbours++;
}
}
}
/* AyStar callback when an route has been found. */
static void River_FoundEndNode(AyStar *aystar, OpenListNode *current)
static void River_FoundEndNode(AyStar *aystar, PathNode *current)
{
River_UserData *data = (River_UserData *)aystar->user_data;
/* First, build the river without worrying about its width. */
uint cur_pos = 0;
for (PathNode *path = &current->path; path != nullptr; path = path->parent, cur_pos++) {
TileIndex tile = path->node.tile;
for (PathNode *path = current->m_parent; path != nullptr; path = path->m_parent, cur_pos++) {
TileIndex tile = path->GetTile();
if (!IsWaterTile(tile)) {
MakeRiverAndModifyDesertZoneAround(tile);
}
@ -1257,30 +1257,18 @@ static void River_FoundEndNode(AyStar *aystar, OpenListNode *current)
uint radius;
cur_pos = 0;
for (PathNode *path = &current->path; path != nullptr; path = path->parent, cur_pos++) {
TileIndex tile = path->node.tile;
for (PathNode *path = current->m_parent; path != nullptr; path = path->m_parent, cur_pos++) {
TileIndex tile = path->GetTile();
/* Check if we should widen river depending on how far we are away from the source. */
current_river_length = DistanceManhattan(data->spring, tile);
radius = std::min(3u, (current_river_length / (long_river_length / 3u)) + 1u);
if (radius > 1) CircularTileSearch(&tile, radius, RiverMakeWider, (void *)&path->node.tile);
if (radius > 1) CircularTileSearch(&tile, radius, RiverMakeWider, (void *)&path->m_key.m_tile);
}
}
}
static const uint RIVER_HASH_SIZE = 8; ///< The number of bits the hash for river finding should have.
/**
* Simple hash function for river tiles to be used by AyStar.
* @param tile The tile to hash.
* @return The hash for the tile.
*/
static uint River_Hash(TileIndex tile, Trackdir)
{
return GB(TileHash(TileX(tile), TileY(tile)), 0, RIVER_HASH_SIZE);
}
/**
* Actually build the river between the begin and end tiles using AyStar.
* @param begin The begin of the river.
@ -1301,14 +1289,11 @@ static void BuildRiver(TileIndex begin, TileIndex end, TileIndex spring, bool ma
finder.user_target = &end;
finder.user_data = &user_data;
finder.Init(River_Hash, 1 << RIVER_HASH_SIZE);
AyStarNode start;
start.tile = begin;
start.direction = INVALID_TRACKDIR;
start.m_tile = begin;
start.m_td = INVALID_TRACKDIR;
finder.AddStartNode(&start, 0);
finder.Main();
finder.Free();
}
/**

179
src/pathfinder/aystar.cpp
View File

@ -13,69 +13,11 @@
* <A HREF='http://en.wikipedia.org/wiki/A-star_search_algorithm'>http://en.wikipedia.org/wiki/A-star_search_algorithm</A>.
*/
/*
* Friendly reminder:
* Call (AyStar).free() when you are done with Aystar. It reserves a lot of memory
* And when not free'd, it can cause system-crashes.
* Also remember that when you stop an algorithm before it is finished, your
* should call clear() yourself!
*/
#include "../../stdafx.h"
#include "../../core/alloc_func.hpp"
#include "aystar.h"
#include "../../safeguards.h"
/**
* This looks in the hash whether a node exists in the closed list.
* @param node Node to search.
* @return The #PathNode if it is available, else \c nullptr
*/
PathNode *AyStar::ClosedListIsInList(const AyStarNode *node)
{
return (PathNode*)this->closedlist_hash.Get(node->tile, node->direction);
}
/**
* This adds a node to the closed list.
* It makes a copy of the data.
* @param node Node to add to the closed list.
*/
void AyStar::ClosedListAdd(const PathNode *node)
{
/* Add a node to the ClosedList */
PathNode *new_node = MallocT<PathNode>(1);
*new_node = *node;
this->closedlist_hash.Set(node->node.tile, node->node.direction, new_node);
}
/**
* Check whether a node is in the open list.
* @param node Node to search.
* @return If the node is available, it is returned, else \c nullptr is returned.
*/
OpenListNode *AyStar::OpenListIsInList(const AyStarNode *node)
{
return (OpenListNode*)this->openlist_hash.Get(node->tile, node->direction);
}
/**
* Gets the best node from the open list.
* It deletes the returned node from the open list.
* @returns the best node available, or \c nullptr of none is found.
*/
OpenListNode *AyStar::OpenListPop()
{
/* Return the item the Queue returns.. the best next OpenList item. */
OpenListNode *res = (OpenListNode*)this->openlist_queue.Pop();
if (res != nullptr) {
this->openlist_hash.DeleteValue(res->path.node.tile, res->path.node.direction);
}
return res;
}
/**
* Adds a node to the open list.
* It makes a copy of node, and puts the pointer of parent in the struct.
@ -83,61 +25,55 @@ OpenListNode *AyStar::OpenListPop()
void AyStar::OpenListAdd(PathNode *parent, const AyStarNode *node, int f, int g)
{
/* Add a new Node to the OpenList */
OpenListNode *new_node = MallocT<OpenListNode>(1);
new_node->g = g;
new_node->path.parent = parent;
new_node->path.node = *node;
this->openlist_hash.Set(node->tile, node->direction, new_node);
/* Add it to the queue */
this->openlist_queue.Push(new_node, f);
PathNode *new_node = this->nodes.CreateNewNode();
new_node->Set(parent, node->m_tile, node->m_td, true);
new_node->m_estimate = f;
new_node->m_cost = g;
this->nodes.InsertOpenNode(*new_node);
}
/**
* Checks one tile and calculate its f-value
*/
void AyStar::CheckTile(AyStarNode *current, OpenListNode *parent)
void AyStar::CheckTile(AyStarNode *current, PathNode *parent)
{
int new_f, new_g, new_h;
PathNode *closedlist_parent;
OpenListNode *check;
/* Check the new node against the ClosedList */
if (this->ClosedListIsInList(current) != nullptr) return;
if (this->nodes.FindClosedNode(*current) != nullptr) return;
/* Calculate the G-value for this node */
new_g = this->CalculateG(this, current, parent);
int new_g = this->CalculateG(this, current, parent);
/* If the value was INVALID_NODE, we don't do anything with this node */
if (new_g == AYSTAR_INVALID_NODE) return;
/* There should not be given any other error-code.. */
assert(new_g >= 0);
/* Add the parent g-value to the new g-value */
new_g += parent->g;
if (this->max_path_cost != 0 && (uint)new_g > this->max_path_cost) return;
new_g += parent->m_cost;
if (this->max_path_cost != 0 && new_g > this->max_path_cost) return;
/* Calculate the h-value */
new_h = this->CalculateH(this, current, parent);
int new_h = this->CalculateH(this, current, parent);
/* There should not be given any error-code.. */
assert(new_h >= 0);
/* The f-value if g + h */
new_f = new_g + new_h;
int new_f = new_g + new_h;
/* Get the pointer to the parent in the ClosedList (the current one is to a copy of the one in the OpenList) */
closedlist_parent = this->ClosedListIsInList(&parent->path.node);
PathNode *closedlist_parent = this->nodes.FindClosedNode(parent->m_key);
/* Check if this item is already in the OpenList */
check = this->OpenListIsInList(current);
PathNode *check = this->nodes.FindOpenNode(*current);
if (check != nullptr) {
/* Yes, check if this g value is lower.. */
if (new_g > check->g) return;
this->openlist_queue.Delete(check, 0);
if (new_g > check->m_cost) return;
this->nodes.PopOpenNode(check->m_key);
/* It is lower, so change it to this item */
check->g = new_g;
check->path.parent = closedlist_parent;
check->m_estimate = new_f;
check->m_cost = new_g;
check->m_parent = closedlist_parent;
/* Re-add it in the openlist_queue. */
this->openlist_queue.Push(check, new_f);
this->nodes.InsertOpenNode(*check);
} else {
/* A new node, add it to the OpenList */
this->OpenListAdd(closedlist_parent, current, new_f, new_g);
@ -155,38 +91,32 @@ void AyStar::CheckTile(AyStarNode *current, OpenListNode *parent)
*/
int AyStar::Loop()
{
int i;
/* Get the best node from OpenList */
OpenListNode *current = this->OpenListPop();
PathNode *current = this->nodes.PopBestOpenNode();
/* If empty, drop an error */
if (current == nullptr) return AYSTAR_EMPTY_OPENLIST;
/* Check for end node and if found, return that code */
if (this->EndNodeCheck(this, current) == AYSTAR_FOUND_END_NODE && (&current->path)->parent != nullptr) {
if (this->EndNodeCheck(this, current) == AYSTAR_FOUND_END_NODE && current->m_parent != nullptr) {
if (this->FoundEndNode != nullptr) {
this->FoundEndNode(this, current);
}
free(current);
return AYSTAR_FOUND_END_NODE;
}
/* Add the node to the ClosedList */
this->ClosedListAdd(&current->path);
this->nodes.InsertClosedNode(*current);
/* Load the neighbours */
this->GetNeighbours(this, current);
/* Go through all neighbours */
for (i = 0; i < this->num_neighbours; i++) {
for (int i = 0; i < this->num_neighbours; i++) {
/* Check and add them to the OpenList if needed */
this->CheckTile(&this->neighbours[i], current);
}
/* Free the node */
free(current);
if (this->max_search_nodes != 0 && this->closedlist_hash.GetSize() >= this->max_search_nodes) {
if (this->max_search_nodes != 0 && this->nodes.ClosedCount() >= this->max_search_nodes) {
/* We've expanded enough nodes */
return AYSTAR_LIMIT_REACHED;
} else {
@ -195,39 +125,6 @@ int AyStar::Loop()
}
}
/**
* This function frees the memory it allocated
*/
void AyStar::Free()
{
this->openlist_queue.Free(false);
/* 2nd argument above is false, below is true, to free the values only
* once */
this->openlist_hash.Delete(true);
this->closedlist_hash.Delete(true);
#ifdef AYSTAR_DEBUG
Debug(misc, 0, "[AyStar] Memory free'd");
#endif
}
/**
* This function make the memory go back to zero.
* This function should be called when you are using the same instance again.
*/
void AyStar::Clear()
{
/* Clean the Queue, but not the elements within. That will be done by
* the hash. */
this->openlist_queue.Clear(false);
/* Clean the hashes */
this->openlist_hash.Clear(true);
this->closedlist_hash.Clear(true);
#ifdef AYSTAR_DEBUG
Debug(misc, 0, "[AyStar] Cleared AyStar");
#endif
}
/**
* This is the function you call to run AyStar.
* @return Possible values:
@ -251,10 +148,6 @@ int AyStar::Main()
default: break;
}
#endif
if (r != AYSTAR_STILL_BUSY) {
/* We're done, clean up */
this->Clear();
}
switch (r) {
case AYSTAR_FOUND_END_NODE: return AYSTAR_FOUND_END_NODE;
@ -272,7 +165,7 @@ int AyStar::Main()
* @param start_node Node to start with.
* @param g the cost for starting with this node.
*/
void AyStar::AddStartNode(AyStarNode *start_node, uint g)
void AyStar::AddStartNode(AyStarNode *start_node, int g)
{
#ifdef AYSTAR_DEBUG
Debug(misc, 0, "[AyStar] Starting A* Algorithm from node ({}, {}, {})\n",
@ -280,23 +173,3 @@ void AyStar::AddStartNode(AyStarNode *start_node, uint g)
#endif
this->OpenListAdd(nullptr, start_node, 0, g);
}
/**
* Initialize an #AyStar. You should fill all appropriate fields before
* calling #Init (see the declaration of #AyStar for which fields are internal).
*/
void AyStar::Init(Hash_HashProc hash, uint num_buckets)
{
/* Allocated the Hash for the OpenList and ClosedList */
this->openlist_hash.Init(hash, num_buckets);
this->closedlist_hash.Init(hash, num_buckets);
/* Set up our sorting queue
* BinaryHeap allocates a block of 1024 nodes
* When that one gets full it reserves another one, till this number
* That is why it can stay this high */
this->openlist_queue.Init(102400);
/* Set a reasonable default limit */
this->max_search_nodes = AYSTAR_DEF_MAX_SEARCH_NODES;
}

63
src/pathfinder/aystar.h
View File

@ -16,9 +16,14 @@
#ifndef AYSTAR_H
#define AYSTAR_H
#include "queue.h"
#include "../../tile_type.h"
#include "../../track_type.h"
#include "../track_func.h"
#include "../misc/hashtable.hpp"
#include "../misc/binaryheap.hpp"
#include "../misc/dbg_helpers.h"
#include "yapf/nodelist.hpp"
#include "yapf/yapf_node.hpp"
static const int AYSTAR_DEF_MAX_SEARCH_NODES = 10000; ///< Reference limit for #AyStar::max_search_nodes
@ -34,26 +39,9 @@ enum AystarStatus {
static const int AYSTAR_INVALID_NODE = -1; ///< Item is not valid (for example, not walkable).
/** Node in the search. */
struct AyStarNode {
TileIndex tile;
Trackdir direction;
};
using AyStarNode = CYapfNodeKeyTrackDir;
/** A path of nodes. */
struct PathNode {
AyStarNode node;
PathNode *parent; ///< The parent of this item.
};
/**
* Internal node.
* @note We do not save the h-value, because it is only needed to calculate the f-value.
* h-value should \em always be the distance left to the end-tile.
*/
struct OpenListNode {
int g;
PathNode path;
struct PathNode : CYapfNodeT<AyStarNode, PathNode> {
};
bool CheckIgnoreFirstTile(const PathNode *node);
@ -74,7 +62,7 @@ struct AyStar;
* - #AYSTAR_FOUND_END_NODE : indicates this is the end tile
* - #AYSTAR_DONE : indicates this is not the end tile (or direction was wrong)
*/
typedef int32_t AyStar_EndNodeCheck(const AyStar *aystar, const OpenListNode *current);
typedef int32_t AyStar_EndNodeCheck(const AyStar *aystar, const PathNode *current);
/**
* Calculate the G-value for the %AyStar algorithm.
@ -82,27 +70,27 @@ typedef int32_t AyStar_EndNodeCheck(const AyStar *aystar, const OpenListNode *cu
* - #AYSTAR_INVALID_NODE : indicates an item is not valid (e.g.: unwalkable)
* - Any value >= 0 : the g-value for this tile
*/
typedef int32_t AyStar_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
typedef int32_t AyStar_CalculateG(AyStar *aystar, AyStarNode *current, PathNode *parent);
/**
* Calculate the H-value for the %AyStar algorithm.
* Mostly, this must return the distance (Manhattan way) between the current point and the end point.
* @return The h-value for this tile (any value >= 0)
*/
typedef int32_t AyStar_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
typedef int32_t AyStar_CalculateH(AyStar *aystar, AyStarNode *current, PathNode *parent);
/**
* This function requests the tiles around the current tile and put them in #neighbours.
* #neighbours is never reset, so if you are not using directions, just leave it alone.
* @warning Never add more #neighbours than memory allocated for it.
*/
typedef void AyStar_GetNeighbours(AyStar *aystar, OpenListNode *current);
typedef void AyStar_GetNeighbours(AyStar *aystar, PathNode *current);
/**
* If the End Node is found, this function is called.
* It can do, for example, calculate the route and put that in an array.
*/
typedef void AyStar_FoundEndNode(AyStar *aystar, OpenListNode *current);
typedef void AyStar_FoundEndNode(AyStar *aystar, PathNode *current);
/**
* %AyStar search algorithm struct.
@ -134,36 +122,25 @@ struct AyStar {
void *user_data;
uint8_t loops_per_tick; ///< How many loops are there called before Main() gives control back to the caller. 0 = until done.
uint max_path_cost; ///< If the g-value goes over this number, it stops searching, 0 = infinite.
uint max_search_nodes; ///< The maximum number of nodes that will be expanded, 0 = infinite.
int max_path_cost; ///< If the g-value goes over this number, it stops searching, 0 = infinite.
int max_search_nodes = AYSTAR_DEF_MAX_SEARCH_NODES; ///< The maximum number of nodes that will be expanded, 0 = infinite.
/* These should be filled with the neighbours of a tile by
* GetNeighbours */
AyStarNode neighbours[12];
uint8_t num_neighbours;
void Init(Hash_HashProc hash, uint num_buckets);
/* These will contain the methods for manipulating the AyStar. Only
* Main() should be called externally */
void AddStartNode(AyStarNode *start_node, uint g);
void AddStartNode(AyStarNode *start_node, int g);
int Main();
int Loop();
void Free();
void Clear();
void CheckTile(AyStarNode *current, OpenListNode *parent);
void CheckTile(AyStarNode *current, PathNode *parent);
protected:
Hash closedlist_hash; ///< The actual closed list.
BinaryHeap openlist_queue; ///< The open queue.
Hash openlist_hash; ///< An extra hash to speed up the process of looking up an element in the open list.
CNodeList_HashTableT<PathNode, 8, 10> nodes;
void OpenListAdd(PathNode *parent, const AyStarNode *node, int f, int g);
OpenListNode *OpenListIsInList(const AyStarNode *node);
OpenListNode *OpenListPop();
void ClosedListAdd(const PathNode *node);
PathNode *ClosedListIsInList(const AyStarNode *node);
};
#endif /* AYSTAR_H */

1
src/pathfinder/pathfinder_type.h
View File

@ -11,7 +11,6 @@
#define PATHFINDER_TYPE_H
#include "../tile_type.h"
#include "aystar.h"
/** Length (penalty) of one tile with YAPF */
static const int YAPF_TILE_LENGTH = 100;

1
src/settings_table.cpp
View File

@ -17,6 +17,7 @@
#include "network/network_func.h"
#include "network/core/config.h"
#include "pathfinder/pathfinder_type.h"
#include "pathfinder/aystar.h"
#include "linkgraph/linkgraphschedule.h"
#include "genworld.h"
#include "train.h"