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CYapfBaseT< Types > Class Template Reference

CYapfBaseT - A-star type path finder base class. More...

#include <yapf_base.hpp>

Inheritance diagram for CYapfBaseT< Types >:
CYapfT< CYapfRail_TypesT< CYapfAnyDepotRail1, CFollowTrackRail, CRailNodeListTrackDir, CYapfDestinationAnyDepotRailT, CYapfFollowAnyDepotRailT > > CYapfT< CYapfRail_TypesT< CYapfAnyDepotRail2, CFollowTrackRailNo90, CRailNodeListTrackDir, CYapfDestinationAnyDepotRailT, CYapfFollowAnyDepotRailT > > CYapfT< CYapfRail_TypesT< CYapfAnySafeTileRail1, CFollowTrackFreeRail, CRailNodeListTrackDir, CYapfDestinationAnySafeTileRailT, CYapfFollowAnySafeTileRailT > > CYapfT< CYapfRail_TypesT< CYapfAnySafeTileRail2, CFollowTrackFreeRailNo90, CRailNodeListTrackDir, CYapfDestinationAnySafeTileRailT, CYapfFollowAnySafeTileRailT > > CYapfT< CYapfRail_TypesT< CYapfRail1, CFollowTrackRail, CRailNodeListTrackDir, CYapfDestinationTileOrStationRailT, CYapfFollowRailT > > CYapfT< CYapfRail_TypesT< CYapfRail2, CFollowTrackRailNo90, CRailNodeListTrackDir, CYapfDestinationTileOrStationRailT, CYapfFollowRailT > > CYapfT< CYapfRoad_TypesT< CYapfRoad1, CRoadNodeListTrackDir, CYapfDestinationTileRoadT > > CYapfT< CYapfRoad_TypesT< CYapfRoad2, CRoadNodeListExitDir, CYapfDestinationTileRoadT > > CYapfT< CYapfRoad_TypesT< CYapfRoadAnyDepot1, CRoadNodeListTrackDir, CYapfDestinationAnyDepotRoadT > > CYapfT< CYapfRoad_TypesT< CYapfRoadAnyDepot2, CRoadNodeListExitDir, CYapfDestinationAnyDepotRoadT > > CYapfT< CYapfShip_TypesT< CYapfShip1, CFollowTrackWater, CShipNodeListTrackDir > > CYapfT< CYapfShip_TypesT< CYapfShip2, CFollowTrackWater, CShipNodeListExitDir > > CYapfT< CYapfShip_TypesT< CYapfShip3, CFollowTrackWaterNo90, CShipNodeListTrackDir > >

Public Types

typedef Types::Tpf Tpf
 the pathfinder class (derived from THIS class)
typedef Types::TrackFollower TrackFollower
typedef Types::NodeList NodeList
 our node list
typedef Types::VehicleType VehicleType
 the type of vehicle
typedef NodeList::Titem Node
 this will be our node type
typedef Node::Key Key
 key to hash tables

Public Member Functions

 CYapfBaseT ()
 default constructor
 ~CYapfBaseT ()
 default destructor
const YAPFSettingsPfGetSettings () const
 return current settings (can be custom - company based - but later)
bool FindPath (const VehicleType *v)
 Main pathfinder routine:
NodeGetBestNode ()
 If path was found return the best node that has reached the destination.
NodeCreateNewNode ()
 Calls NodeList::CreateNewNode() - allocates new node that can be filled and used as argument for AddStartupNode() or AddNewNode()
void AddStartupNode (Node &n)
 Add new node (created by CreateNewNode and filled with data) into open list.
void AddMultipleNodes (Node *parent, const TrackFollower &tf)
 add multiple nodes - direct children of the given node
void PruneIntermediateNodeBranch ()
 In some cases an intermediate node branch should be pruned.
void AddNewNode (Node &n, const TrackFollower &tf)
 AddNewNode() - called by Tderived::PfFollowNode() for each child node.
const VehicleTypeGetVehicle () const
void DumpBase (DumpTarget &dmp) const

Data Fields

NodeList m_nodes
 node list multi-container
CPerformanceTimer m_perf_cost
 stats - total CPU time of this run
CPerformanceTimer m_perf_slope_cost
 stats - slope calculation CPU time
CPerformanceTimer m_perf_ts_cost
 stats - GetTrackStatus() CPU time
CPerformanceTimer m_perf_other_cost
 stats - other CPU time
int m_num_steps
 this is there for debugging purposes (hope it doesn't hurt)

Protected Member Functions

TpfYapf ()
 to access inherited path finder

Protected Attributes

Nodem_pBestDestNode
 pointer to the destination node found at last round
Nodem_pBestIntermediateNode
 here should be node closest to the destination if path not found
const YAPFSettingsm_settings
 current settings (_settings_game.yapf)
int m_max_search_nodes
 maximum number of nodes we are allowed to visit before we give up
const VehicleTypem_veh
 vehicle that we are trying to drive
int m_stats_cost_calcs
 stats - how many node's costs were calculated
int m_stats_cache_hits
 stats - how many node's costs were reused from cache

Detailed Description

template<class Types>
class CYapfBaseT< Types >

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:

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.

Requirements to your pathfinder class derived from CYapfBaseT:

Your pathfinder derived class needs to implement following methods: inline void PfSetStartupNodes() inline void PfFollowNode(Node &org) inline bool PfCalcCost(Node &n) inline bool PfCalcEstimate(Node &n) inline 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).

Definition at line 51 of file yapf_base.hpp.

Member Function Documentation

template<class Types >
void CYapfBaseT< Types >::AddNewNode ( Node n,
const TrackFollower &  tf 
)
inline
template<class Types >
bool CYapfBaseT< Types >::FindPath ( const VehicleType v)
inline

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)
      Returns
      true if the path was found

Definition at line 121 of file yapf_base.hpp.

References DEBUG, CYapfBaseT< Types >::m_max_search_nodes, CYapfBaseT< Types >::m_nodes, CYapfBaseT< Types >::m_num_steps, CYapfBaseT< Types >::m_pBestDestNode, CYapfBaseT< Types >::m_perf_cost, CYapfBaseT< Types >::m_perf_other_cost, CYapfBaseT< Types >::m_perf_slope_cost, CYapfBaseT< Types >::m_perf_ts_cost, CYapfBaseT< Types >::m_stats_cache_hits, CYapfBaseT< Types >::m_stats_cost_calcs, CYapfBaseT< Types >::m_veh, and CYapfBaseT< Types >::Yapf().

template<class Types >
Node* CYapfBaseT< Types >::GetBestNode ( )
inline

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).

Definition at line 185 of file yapf_base.hpp.

References CYapfBaseT< Types >::m_pBestDestNode, and CYapfBaseT< Types >::m_pBestIntermediateNode.

template<class Types >
void CYapfBaseT< Types >::PruneIntermediateNodeBranch ( )
inline

In some cases an intermediate node branch should be pruned.

The most prominent case is when a red EOL signal is encountered, but there was a segment change (e.g. a rail type change) before that. If the branch would not be pruned, the rail type change location would remain the best intermediate node, and thus the vehicle would still go towards the red EOL signal.

Definition at line 234 of file yapf_base.hpp.

References CYapfBaseT< Types >::m_pBestIntermediateNode, and CYapfBaseT< Types >::Yapf().


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