--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/yapf/yapf_base.hpp Sat May 27 16:12:16 2006 +0000
@@ -0,0 +1,329 @@
+/* $Id$ */
+
+#ifndef YAPF_BASE_HPP
+#define YAPF_BASE_HPP
+
+EXTERN_C_BEGIN
+#include "../debug.h"
+EXTERN_C_END
+
+#include "fixedsizearray.hpp"
+#include "blob.hpp"
+#include "nodelist.hpp"
+
+extern int _total_pf_time_us;
+
+/** CYapfBaseT - A-star type path finder base class.
+ Derive your own pathfinder from it. You must provide the following template argument:
+ Types - used as collection of local types used in pathfinder
+
+ Requirements for the Types struct:
+ ----------------------------------
+ The following types must be defined in the 'Types' argument:
+ - Types::Tpf - your pathfinder derived from CYapfBaseT
+ - Types::NodeList - open/closed node list (look at CNodeList_HashTableT)
+ NodeList needs to have defined local type Titem - defines the pathfinder node type.
+ Node needs to define local type Key - the node key in the collection ()
+
+ For node list you can use template class CNodeList_HashTableT, for which
+ you need to declare only your node type. Look at test_yapf.h for an example.
+
+
+ Requrements to your pathfinder class derived from CYapfBaseT:
+ -------------------------------------------------------------
+ Your pathfinder derived class needs to implement following methods:
+ FORCEINLINE void PfSetStartupNodes()
+ FORCEINLINE void PfFollowNode(Node& org)
+ FORCEINLINE bool PfCalcCost(Node& n)
+ FORCEINLINE bool PfCalcEstimate(Node& n)
+ FORCEINLINE bool PfDetectDestination(Node& n)
+
+ For more details about those methods, look at the end of CYapfBaseT
+ declaration. There are some examples. For another example look at
+ test_yapf.h (part or unittest project).
+*/
+template <class Types>
+class CYapfBaseT {
+public:
+ typedef typename Types::Tpf Tpf;
+ typedef typename Types::NodeList NodeList; ///< our node list
+ typedef typename NodeList::Titem Node; ///< this will be our node type
+ typedef typename Node::Key Key; ///< key to hash tables
+
+
+ NodeList m_nodes; ///< node list multi-container
+protected:
+ Node* m_pBestDestNode; ///< pointer to the destination node found at last round
+ Node* m_pBestIntermediateNode;
+ const YapfSettings *m_settings;
+ int m_max_search_nodes;
+ Vehicle* m_veh;
+
+ int m_stats_cost_calcs;
+ int m_stats_cache_hits;
+
+public:
+ CPerformanceTimer m_perf_cost;
+ CPerformanceTimer m_perf_slope_cost;
+ CPerformanceTimer m_perf_ts_cost;
+ CPerformanceTimer m_perf_other_cost;
+
+public:
+ int m_num_steps; ///< this is there for debugging purposes (hope it doesn't hurt)
+
+public:
+ // default constructor
+ FORCEINLINE CYapfBaseT()
+ : m_pBestDestNode(NULL)
+ , m_pBestIntermediateNode(NULL)
+#if defined(UNITTEST)
+ , m_settings(NULL)
+ , m_max_search_nodes(100000)
+#else
+ , m_settings(&_patches.yapf)
+ , m_max_search_nodes(PfGetSettings().max_search_nodes)
+#endif
+ , m_veh(NULL)
+ , m_stats_cost_calcs(0)
+ , m_stats_cache_hits(0)
+ , m_num_steps(0)
+ {
+ }
+
+ ~CYapfBaseT() {}
+
+protected:
+ FORCEINLINE Tpf& Yapf() {return *static_cast<Tpf*>(this);}
+
+public:
+ FORCEINLINE const YapfSettings& PfGetSettings() const
+ {
+ return *m_settings;
+ }
+
+ /** Main pathfinder routine:
+ - set startup node(s)
+ - main loop that stops if:
+ - the destination was found
+ - or the open list is empty (no route to destination).
+ - or the maximum amount of loops reached - m_max_search_nodes (default = 10000)
+ @return true if the path was found */
+ inline bool FindPath(Vehicle* v)
+ {
+ m_veh = v;
+
+ CPerformanceTimer perf;
+ perf.Start();
+ Yapf().PfSetStartupNodes();
+
+ while (true) {
+ m_num_steps++;
+ Node& n = m_nodes.GetBestOpenNode();
+ if (&n == NULL)
+ break;
+
+ // if the best open node was worse than the best path found, we can finish
+ if (m_pBestDestNode != NULL && m_pBestDestNode->GetCost() < n.GetCostEstimate())
+ break;
+
+ Yapf().PfFollowNode(n);
+ if (m_max_search_nodes == 0 || m_nodes.ClosedCount() < m_max_search_nodes) {
+ m_nodes.PopOpenNode(n.GetKey());
+ m_nodes.InsertClosedNode(n);
+ } else {
+ m_pBestDestNode = m_pBestIntermediateNode;
+ break;
+ }
+ }
+ bool bDestFound = (m_pBestDestNode != NULL);
+
+ int16 veh_idx = (m_veh != NULL) ? m_veh->unitnumber : 0;
+
+// if (veh_idx != 433) return bDestFound;
+
+ perf.Stop();
+ int t = perf.Get(1000000);
+ _total_pf_time_us += t;
+ char ttc = Yapf().TransportTypeChar();
+ float cache_hit_ratio = (float)m_stats_cache_hits / (float)(m_stats_cache_hits + m_stats_cost_calcs) * 100.0f;
+ int cost = bDestFound ? m_pBestDestNode->m_cost : -1;
+ int dist = bDestFound ? m_pBestDestNode->m_estimate - m_pBestDestNode->m_cost : -1;
+#ifdef UNITTEST
+ printf("%c%c%4d-%6d us -%5d rounds -%4d open -%5d closed - CHR %4.1f%% - c/d(%d, %d) - c%d(sc%d, ts%d, o%d) -- \n", bDestFound ? '-' : '!', ttc, veh_idx, t, m_num_steps, m_nodes.OpenCount(), m_nodes.ClosedCount(), cache_hit_ratio, cost, dist, m_perf_cost.Get(1000000), m_perf_slope_cost.Get(1000000), m_perf_ts_cost.Get(1000000), m_perf_other_cost.Get(1000000));
+#else
+ DEBUG(yapf, 1)("[YAPF][YAPF%c]%c%4d- %d us - %d rounds - %d open - %d closed - CHR %4.1f%% - c%d(sc%d, ts%d, o%d) -- ", ttc, bDestFound ? '-' : '!', veh_idx, t, m_num_steps, m_nodes.OpenCount(), m_nodes.ClosedCount(), cache_hit_ratio, cost, dist, m_perf_cost.Get(1000000), m_perf_slope_cost.Get(1000000), m_perf_ts_cost.Get(1000000), m_perf_other_cost.Get(1000000));
+#endif
+ return bDestFound;
+ }
+
+ /** If path was found return the best node that has reached the destination. Otherwise
+ return the best visited node (which was nearest to the destination).
+ */
+ FORCEINLINE Node& GetBestNode()
+ {
+ return (m_pBestDestNode != NULL) ? *m_pBestDestNode : *m_pBestIntermediateNode;
+ }
+
+ /** Calls NodeList::CreateNewNode() - allocates new node that can be filled and used
+ as argument for AddStartupNode() or AddNewNode()
+ */
+ FORCEINLINE Node& CreateNewNode()
+ {
+ Node& node = *m_nodes.CreateNewNode();
+ return node;
+ }
+
+ /** Add new node (created by CreateNewNode and filled with data) into open list */
+ FORCEINLINE void AddStartupNode(Node& n)
+ {
+ Yapf().PfNodeCacheFetch(n);
+ m_nodes.InsertOpenNode(n);
+ }
+
+ /** add multiple nodes - direct children of the given node */
+ FORCEINLINE void AddMultipleNodes(Node* parent, TileIndex tile, TrackdirBits td_bits)
+ {
+ for (TrackdirBits rtds = td_bits; rtds != TRACKDIR_BIT_NONE; rtds = (TrackdirBits)KillFirstBit2x64(rtds)) {
+ Trackdir td = (Trackdir)FindFirstBit2x64(rtds);
+ Node& n = Yapf().CreateNewNode();
+ n.Set(parent, tile, td);
+ Yapf().AddNewNode(n);
+ }
+ }
+
+ /** AddNewNode() - called by Tderived::PfFollowNode() for each child node.
+ Nodes are evaluated here and added into open list */
+ void AddNewNode(Node& n)
+ {
+ // evaluate the node
+ bool bCached = Yapf().PfNodeCacheFetch(n);
+ if (!bCached) {
+ m_stats_cost_calcs++;
+ } else {
+ m_stats_cache_hits++;
+ }
+
+ bool bValid = Yapf().PfCalcCost(n);
+
+ if (bCached) {
+ Yapf().PfNodeCacheFlush(n);
+ }
+
+ if (bValid) bValid = Yapf().PfCalcEstimate(n);
+
+ // have the cost or estimate callbacks marked this node as invalid?
+ if (!bValid) return;
+
+ // detect the destination
+ bool bDestination = Yapf().PfDetectDestination(n);
+ if (bDestination) {
+ if (m_pBestDestNode == NULL || n < *m_pBestDestNode) {
+ m_pBestDestNode = &n;
+ }
+ m_nodes.FoundBestNode(n);
+ return;
+ }
+
+ if (m_max_search_nodes > 0 && (m_pBestIntermediateNode == NULL || (m_pBestIntermediateNode->GetCostEstimate() - m_pBestIntermediateNode->GetCost()) > (n.GetCostEstimate() - n.GetCost()))) {
+ m_pBestIntermediateNode = &n;
+ }
+
+ // check new node against open list
+ Node& openNode = m_nodes.FindOpenNode(n.GetKey());
+ if (&openNode != NULL) {
+ // another node exists with the same key in the open list
+ // is it better than new one?
+ if (n.GetCostEstimate() < openNode.GetCostEstimate()) {
+ // update the old node by value from new one
+ m_nodes.PopOpenNode(n.GetKey());
+ openNode = n;
+ // add the updated old node back to open list
+ m_nodes.InsertOpenNode(openNode);
+ }
+ return;
+ }
+
+ // check new node against closed list
+ Node& closedNode = m_nodes.FindClosedNode(n.GetKey());
+ if (&closedNode != NULL) {
+ // another node exists with the same key in the closed list
+ // is it better than new one?
+ int node_est = n.GetCostEstimate();
+ int closed_est = closedNode.GetCostEstimate();
+ if (node_est < closed_est) {
+ // If this assert occurs, you have probably problem in
+ // your Tderived::PfCalcCost() or Tderived::PfCalcEstimate().
+ // The problem could be:
+ // - PfCalcEstimate() gives too large numbers
+ // - PfCalcCost() gives too small numbers
+ // - You have used negative cost penalty in some cases (cost bonus)
+ assert(0);
+
+ return;
+ }
+ return;
+ }
+ // the new node is really new
+ // add it to the open list
+ m_nodes.InsertOpenNode(n);
+ }
+
+ Vehicle* GetVehicle() const {return m_veh;}
+
+ // methods that should be implemented at derived class Types::Tpf (derived from CYapfBaseT)
+
+#if 0
+ /** Example: PfSetStartupNodes() - set source (origin) nodes */
+ FORCEINLINE void PfSetStartupNodes()
+ {
+ // example:
+ Node& n1 = *base::m_nodes.CreateNewNode();
+ .
+ . // setup node members here
+ .
+ base::m_nodes.InsertOpenNode(n1);
+ }
+
+ /** Example: PfFollowNode() - set following (child) nodes of the given node */
+ FORCEINLINE void PfFollowNode(Node& org)
+ {
+ for (each follower of node org) {
+ Node& n = *base::m_nodes.CreateNewNode();
+ .
+ . // setup node members here
+ .
+ n.m_parent = &org; // set node's parent to allow back tracking
+ AddNewNode(n);
+ }
+ }
+
+ /** Example: PfCalcCost() - set path cost from origin to the given node */
+ FORCEINLINE bool PfCalcCost(Node& n)
+ {
+ // evaluate last step cost
+ int cost = ...;
+ // set the node cost as sum of parent's cost and last step cost
+ n.m_cost = n.m_parent->m_cost + cost;
+ return true; // true if node is valid follower (i.e. no obstacle was found)
+ }
+
+ /** Example: PfCalcEstimate() - set path cost estimate from origin to the target through given node */
+ FORCEINLINE bool PfCalcEstimate(Node& n)
+ {
+ // evaluate the distance to our destination
+ int distance = ...;
+ // set estimate as sum of cost from origin + distance to the target
+ n.m_estimate = n.m_cost + distance;
+ return true; // true if node is valid (i.e. not too far away :)
+ }
+
+ /** Example: PfDetectDestination() - return true if the given node is our destination */
+ FORCEINLINE bool PfDetectDestination(Node& n)
+ {
+ bool bDest = (n.m_key.m_x == m_x2) && (n.m_key.m_y == m_y2);
+ return bDest;
+ }
+#endif
+};
+
+#endif /* YAPF_BASE_HPP */