diff --git a/src/aystar.cpp b/src/aystar.cpp deleted file mode 100644 --- a/src/aystar.cpp +++ /dev/null @@ -1,306 +0,0 @@ -/* $Id$ */ - -/* - * This file is part of OpenTTD. - * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. - * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. - * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see . - */ - -/** @file aystar.cpp Implementation of A*. */ - -/* - * This file has the core function for AyStar - * AyStar is a fast pathfinding routine and is used for things like - * AI_pathfinding and Train_pathfinding. - * For more information about AyStar (A* Algorithm), you can look at - * http://en.wikipedia.org/wiki/A-star_search_algorithm - */ - -/* - * 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 "aystar.h" -#include "core/alloc_func.hpp" - -int _aystar_stats_open_size; -int _aystar_stats_closed_size; - -/* This looks in the Hash if a node exists in ClosedList - * If so, it returns the PathNode, else NULL */ -static PathNode *AyStarMain_ClosedList_IsInList(AyStar *aystar, const AyStarNode *node) -{ - return (PathNode*)Hash_Get(&aystar->ClosedListHash, node->tile, node->direction); -} - -/* This adds a node to the ClosedList - * It makes a copy of the data */ -static void AyStarMain_ClosedList_Add(AyStar *aystar, const PathNode *node) -{ - /* Add a node to the ClosedList */ - PathNode *new_node = MallocT(1); - *new_node = *node; - Hash_Set(&aystar->ClosedListHash, node->node.tile, node->node.direction, new_node); -} - -/* Checks if a node is in the OpenList - * If so, it returns the OpenListNode, else NULL */ -static OpenListNode *AyStarMain_OpenList_IsInList(AyStar *aystar, const AyStarNode *node) -{ - return (OpenListNode*)Hash_Get(&aystar->OpenListHash, node->tile, node->direction); -} - -/* Gets the best node from OpenList - * returns the best node, or NULL of none is found - * Also it deletes the node from the OpenList */ -static OpenListNode *AyStarMain_OpenList_Pop(AyStar *aystar) -{ - /* Return the item the Queue returns.. the best next OpenList item. */ - OpenListNode *res = (OpenListNode*)aystar->OpenListQueue.pop(&aystar->OpenListQueue); - if (res != NULL) { - Hash_Delete(&aystar->OpenListHash, res->path.node.tile, res->path.node.direction); - } - - return res; -} - -/* Adds a node to the OpenList - * It makes a copy of node, and puts the pointer of parent in the struct */ -static void AyStarMain_OpenList_Add(AyStar *aystar, PathNode *parent, const AyStarNode *node, int f, int g) -{ - /* Add a new Node to the OpenList */ - OpenListNode *new_node = MallocT(1); - new_node->g = g; - new_node->path.parent = parent; - new_node->path.node = *node; - Hash_Set(&aystar->OpenListHash, node->tile, node->direction, new_node); - - /* Add it to the queue */ - aystar->OpenListQueue.push(&aystar->OpenListQueue, new_node, f); -} - -/* - * Checks one tile and calculate his f-value - * return values: - * AYSTAR_DONE : indicates we are done - */ -static int AyStarMain_CheckTile(AyStar *aystar, AyStarNode *current, OpenListNode *parent) -{ - int new_f, new_g, new_h; - PathNode *closedlist_parent; - OpenListNode *check; - - /* Check the new node against the ClosedList */ - if (AyStarMain_ClosedList_IsInList(aystar, current) != NULL) return AYSTAR_DONE; - - /* Calculate the G-value for this node */ - new_g = aystar->CalculateG(aystar, current, parent); - /* If the value was INVALID_NODE, we don't do anything with this node */ - if (new_g == AYSTAR_INVALID_NODE) return AYSTAR_DONE; - - /* 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 (aystar->max_path_cost != 0 && (uint)new_g > aystar->max_path_cost) return AYSTAR_DONE; - - /* Calculate the h-value */ - new_h = aystar->CalculateH(aystar, 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; - - /* Get the pointer to the parent in the ClosedList (the currentone is to a copy of the one in the OpenList) */ - closedlist_parent = AyStarMain_ClosedList_IsInList(aystar, &parent->path.node); - - /* Check if this item is already in the OpenList */ - check = AyStarMain_OpenList_IsInList(aystar, current); - if (check != NULL) { - uint i; - /* Yes, check if this g value is lower.. */ - if (new_g > check->g) return AYSTAR_DONE; - aystar->OpenListQueue.del(&aystar->OpenListQueue, check, 0); - /* It is lower, so change it to this item */ - check->g = new_g; - check->path.parent = closedlist_parent; - /* Copy user data, will probably have changed */ - for (i = 0; i < lengthof(current->user_data); i++) { - check->path.node.user_data[i] = current->user_data[i]; - } - /* Readd him in the OpenListQueue */ - aystar->OpenListQueue.push(&aystar->OpenListQueue, check, new_f); - } else { - /* A new node, add him to the OpenList */ - AyStarMain_OpenList_Add(aystar, closedlist_parent, current, new_f, new_g); - } - - return AYSTAR_DONE; -} - -/* - * This function is the core of AyStar. It handles one item and checks - * his neighbour items. If they are valid, they are added to be checked too. - * return values: - * AYSTAR_EMPTY_OPENLIST : indicates all items are tested, and no path - * has been found. - * AYSTAR_LIMIT_REACHED : Indicates that the max_nodes limit has been - * reached. - * AYSTAR_FOUND_END_NODE : indicates we found the end. Path_found now is true, and in path is the path found. - * AYSTAR_STILL_BUSY : indicates we have done this tile, did not found the path yet, and have items left to try. - */ -static int AyStarMain_Loop(AyStar *aystar) -{ - int i, r; - - /* Get the best node from OpenList */ - OpenListNode *current = AyStarMain_OpenList_Pop(aystar); - /* If empty, drop an error */ - if (current == NULL) return AYSTAR_EMPTY_OPENLIST; - - /* Check for end node and if found, return that code */ - if (aystar->EndNodeCheck(aystar, current) == AYSTAR_FOUND_END_NODE) { - if (aystar->FoundEndNode != NULL) - aystar->FoundEndNode(aystar, current); - free(current); - return AYSTAR_FOUND_END_NODE; - } - - /* Add the node to the ClosedList */ - AyStarMain_ClosedList_Add(aystar, ¤t->path); - - /* Load the neighbours */ - aystar->GetNeighbours(aystar, current); - - /* Go through all neighbours */ - for (i = 0; i < aystar->num_neighbours; i++) { - /* Check and add them to the OpenList if needed */ - r = aystar->checktile(aystar, &aystar->neighbours[i], current); - } - - /* Free the node */ - free(current); - - if (aystar->max_search_nodes != 0 && Hash_Size(&aystar->ClosedListHash) >= aystar->max_search_nodes) { - /* We've expanded enough nodes */ - return AYSTAR_LIMIT_REACHED; - } else { - /* Return that we are still busy */ - return AYSTAR_STILL_BUSY; - } -} - -/* - * This function frees the memory it allocated - */ -static void AyStarMain_Free(AyStar *aystar) -{ - aystar->OpenListQueue.free(&aystar->OpenListQueue, false); - /* 2nd argument above is false, below is true, to free the values only - * once */ - delete_Hash(&aystar->OpenListHash, true); - delete_Hash(&aystar->ClosedListHash, true); -#ifdef AYSTAR_DEBUG - printf("[AyStar] Memory free'd\n"); -#endif -} - -/* - * This function make the memory go back to zero - * This function should be called when you are using the same instance again. - */ -void AyStarMain_Clear(AyStar *aystar) -{ - /* Clean the Queue, but not the elements within. That will be done by - * the hash. */ - aystar->OpenListQueue.clear(&aystar->OpenListQueue, false); - /* Clean the hashes */ - clear_Hash(&aystar->OpenListHash, true); - clear_Hash(&aystar->ClosedListHash, true); - -#ifdef AYSTAR_DEBUG - printf("[AyStar] Cleared AyStar\n"); -#endif -} - -/* - * This is the function you call to run AyStar. - * return values: - * AYSTAR_FOUND_END_NODE : indicates we found an end node. - * AYSTAR_NO_PATH : indicates that there was no path found. - * AYSTAR_STILL_BUSY : indicates we have done some checked, that we did not found the path yet, and that we still have items left to try. - * When the algorithm is done (when the return value is not AYSTAR_STILL_BUSY) - * aystar->clear() is called. Note that when you stop the algorithm halfway, - * you should still call clear() yourself! - */ -int AyStarMain_Main(AyStar *aystar) -{ - int r, i = 0; - /* Loop through the OpenList - * Quit if result is no AYSTAR_STILL_BUSY or is more than loops_per_tick */ - while ((r = aystar->loop(aystar)) == AYSTAR_STILL_BUSY && (aystar->loops_per_tick == 0 || ++i < aystar->loops_per_tick)) { } -#ifdef AYSTAR_DEBUG - switch (r) { - case AYSTAR_FOUND_END_NODE: printf("[AyStar] Found path!\n"); break; - case AYSTAR_EMPTY_OPENLIST: printf("[AyStar] OpenList run dry, no path found\n"); break; - case AYSTAR_LIMIT_REACHED: printf("[AyStar] Exceeded search_nodes, no path found\n"); break; - default: break; - } -#endif - if (r != AYSTAR_STILL_BUSY) { - /* We're done, clean up */ - _aystar_stats_open_size = aystar->OpenListHash.size; - _aystar_stats_closed_size = aystar->ClosedListHash.size; - aystar->clear(aystar); - } - - switch (r) { - case AYSTAR_FOUND_END_NODE: return AYSTAR_FOUND_END_NODE; - case AYSTAR_EMPTY_OPENLIST: - case AYSTAR_LIMIT_REACHED: return AYSTAR_NO_PATH; - default: return AYSTAR_STILL_BUSY; - } -} - -/* - * Adds a node from where to start an algorithm. Multiple nodes can be added - * if wanted. You should make sure that clear() is called before adding nodes - * if the AyStar has been used before (though the normal main loop calls - * clear() automatically when the algorithm finishes - * g is the cost for starting with this node. - */ -static void AyStarMain_AddStartNode(AyStar *aystar, AyStarNode *start_node, uint g) -{ -#ifdef AYSTAR_DEBUG - printf("[AyStar] Starting A* Algorithm from node (%d, %d, %d)\n", - TileX(start_node->tile), TileY(start_node->tile), start_node->direction); -#endif - AyStarMain_OpenList_Add(aystar, NULL, start_node, 0, g); -} - -void init_AyStar(AyStar *aystar, Hash_HashProc hash, uint num_buckets) -{ - /* Allocated the Hash for the OpenList and ClosedList */ - init_Hash(&aystar->OpenListHash, hash, num_buckets); - init_Hash(&aystar->ClosedListHash, hash, num_buckets); - - /* Set up our sorting queue - * BinaryHeap allocates a block of 1024 nodes - * When thatone gets full it reserves an otherone, till this number - * That is why it can stay this high */ - init_BinaryHeap(&aystar->OpenListQueue, 102400); - - aystar->addstart = AyStarMain_AddStartNode; - aystar->main = AyStarMain_Main; - aystar->loop = AyStarMain_Loop; - aystar->free = AyStarMain_Free; - aystar->clear = AyStarMain_Clear; - aystar->checktile = AyStarMain_CheckTile; -}