TestAI Class Reference

This is a test version of the AI, which can be used to create new AIs, and compare them with the current AI. More...

#include <test_ai.hpp>

Inheritance diagram for TestAI:

Classes
class	CrashTypes

Public Member Functions
	TestAI (AbstractKart *kart)
virtual void	update (int ticks)
	Updates the ai base controller each time step.
virtual void	reset ()
virtual const irr::core::stringw &	getNamePostfix () const
Public Member Functions inherited from AIBaseLapController
	AIBaseLapController (AbstractKart *kart)
	This is the base class for all AIs.
virtual void	reset ()
Public Member Functions inherited from AIBaseController
	AIBaseController (AbstractKart *kart)
virtual void	reset () OVERRIDE
virtual bool	disableSlipstreamBonus () const OVERRIDE
	Certain AI levels will not receive a slipstream bonus in order to be not as hard.
virtual void	crashed (const Material *m) OVERRIDE
	This is called when the kart crashed with the terrain.
virtual void	crashed (const AbstractKart *k) OVERRIDE
virtual void	handleZipper (bool play_sound) OVERRIDE
virtual void	finishedRace (float time) OVERRIDE
	Called whan this controller's kart finishes the last lap.
virtual void	collectedItem (const ItemState &item, float previous_energy=0) OVERRIDE
virtual void	setPosition (int p) OVERRIDE
virtual bool	isPlayerController () const OVERRIDE
	This function checks if this player is not an AI, i.e.
virtual bool	isLocalPlayerController () const OVERRIDE
	This function checks if this is a local player.
virtual bool	action (PlayerAction action, int value, bool dry_run=false) OVERRIDE
	Default: ignore actions.
virtual void	skidBonusTriggered () OVERRIDE
virtual bool	saveState (BareNetworkString *buffer) const OVERRIDE
virtual void	rewindTo (BareNetworkString *buffer) OVERRIDE
void	setNetworkAI (bool val)
virtual void	update (int ticks) OVERRIDE
Public Member Functions inherited from Controller
	Controller (AbstractKart *kart)
	Constructor, saves the kart pointer and a pointer to the KartControl of the kart.
virtual void	reset ()=0
virtual void	update (int ticks)=0
virtual void	handleZipper (bool play_sound)=0
virtual void	collectedItem (const ItemState &item, float previous_energy=0)=0
virtual void	crashed (const AbstractKart *k)=0
virtual void	crashed (const Material *m)=0
virtual void	setPosition (int p)=0
virtual bool	isLocalPlayerController () const =0
	This function checks if this is a local player.
virtual bool	isPlayerController () const =0
	This function checks if this player is not an AI, i.e.
virtual bool	disableSlipstreamBonus () const =0
virtual bool	saveState (BareNetworkString *buffer) const =0
virtual void	rewindTo (BareNetworkString *buffer)=0
virtual void	rumble (float strength_low, float strength_high, uint16_t duration)
virtual void	setControllerName (const std::string &name)
	Sets the controller name for this controller.
const std::string &	getControllerName () const
	Returns the name of this controller.
virtual bool	action (PlayerAction action, int value, bool dry_run=false)=0
	Default: ignore actions.
virtual void	newLap (int lap)=0
	Callback whenever a new lap is triggered.
virtual void	skidBonusTriggered ()=0
virtual void	finishedRace (float time)=0
	Called whan this controller's kart finishes the last lap.
virtual KartControl *	getControls ()
	Get a pointer on the kart controls.
void	setControls (KartControl *kc)
virtual bool	canGetAchievements () const
	Only local players can get achievements.
virtual core::stringw	getName (bool include_handicap_string=true) const
	Display name of the controller.
AbstractKart *	getKart () const
	Returns the kart controlled by this controller.

Protected Member Functions
virtual unsigned int	getNextSector (unsigned int index)
	Returns the next sector of the given sector index.
Protected Member Functions inherited from AIBaseLapController
virtual void	update (int ticks)
	Updates the ai base controller each time step.
virtual unsigned int	getNextSector (unsigned int index)
	Returns the next sector of the given sector index.
virtual void	newLap (int lap)
	Triggers a recomputation of the path to use, so that the AI does not always use the same way.
float	steerToAngle (const unsigned int sector, const float angle)
	This function steers towards a given angle.
void	computePath ()
	Computes a path for the AI to follow.
virtual void	raceFinished ()
	Nothing special to do when the race is finished.
Protected Member Functions inherited from AIBaseController
void	setControllerName (const std::string &name) OVERRIDE
	In debug mode when the user specified –ai-debug on the command line set the name of the controller as on-screen text, so that the different AI controllers can be distinguished.
float	steerToPoint (const Vec3 &point)
	Computes the steering angle to reach a certain point.
float	normalizeAngle (float angle)
	Normalises an angle to be between -pi and _ pi.
bool	isStuck () const
	This can be called to detect if the kart is stuck (i.e.
void	determineTurnRadius (const Vec3 &end, Vec3 *center, float *radius) const
	Determine the center point and radius of a circle given two points on the circle and the tangent at the first point.
virtual void	setSteering (float angle, float dt)
	Converts the steering angle to a lr steering in the range of -1 to 1.
virtual bool	canSkid (float steer_fraction)=0
	Return true if AI can skid now.

Private Types
enum	{ SKID_PROBAB_NOT_YET , SKID_PROBAB_NO_SKID , SKID_PROBAB_SKID }
	This implements a simple finite state machine: it starts in NOT_YET. More...
enum	{ PSA_DEFAULT , PSA_FIXED , PSA_NEW }
	Determines the algorithm to use to select the point-to-aim-for There are three different Point Selection Algorithms: More...

Private Member Functions
void	handleRaceStart ()
void	handleAcceleration (int ticks)
void	handleSteering (float dt)
void	handleItems (const float dt)
void	handleRescue (const float dt)
void	handleBraking ()
void	handleNitroAndZipper ()
void	computeNearestKarts ()
void	handleItemCollectionAndAvoidance (Vec3 *aim_point, int last_node)
bool	handleSelectedItem (Vec3 kart_aim_direction, Vec3 *aim_point)
bool	steerToAvoid (const std::vector< const ItemState * > &items_to_avoid, const core::line3df &line_to_target, Vec3 *aim_point)
bool	hitBadItemWhenAimAt (const ItemState *item, const std::vector< const ItemState * > &items_to_avoid)
void	evaluateItems (const ItemState *item, Vec3 kart_aim_direction, std::vector< const ItemState * > *items_to_avoid, std::vector< const ItemState * > *items_to_collect)
void	checkCrashes (const Vec3 &pos)
void	findNonCrashingPointFixed (Vec3 *result, int *last_node)
void	findNonCrashingPointNew (Vec3 *result, int *last_node)
void	findNonCrashingPoint (Vec3 *result, int *last_node)
void	determineTrackDirection ()
virtual bool	canSkid (float steer_fraction)
	Return true if AI can skid now.
virtual void	setSteering (float angle, float dt)
	Converts the steering angle to a lr steering in the range of -1 to 1.
void	handleCurve ()

Private Attributes
class TestAI::CrashTypes	m_crashes
RaceManager::AISuperPower	m_superpower
AbstractKart *	m_kart_ahead
	Pointer to the closest kart ahead of this kart.
float	m_distance_ahead
	Distance to the kart ahead.
AbstractKart *	m_kart_behind
	Pointer to the closest kart behind this kart.
float	m_distance_behind
	Distance to the kard behind.
int	m_start_delay
	The actual start delay used in ticks.
float	m_time_since_last_shot
	Time an item has been collected and not used.
float	m_time_since_stuck
int	m_start_kart_crash_direction
	Direction of crash: -1 = left, 1 = right, 0 = no crash.
DriveNode::DirectionType	m_current_track_direction
	The direction of the track where the kart is on atm.
float	m_current_curve_radius
	The radius of the curve the kart is currently driving.
Vec3	m_curve_center
	Stores the center of the curve (if the kart is in a curve, otherwise undefined).
unsigned int	m_last_direction_node
	The index of the last node with the same direction as the current node the kart is on.
const ItemState *	m_item_to_collect
	If set an item that the AI should aim for.
bool	m_avoid_item_close
	True if items to avoid are close by.
float	m_distance_to_player
	Distance to the player, used for rubber-banding.
RandomGenerator	m_random_skid
	A random number generator to decide if the AI should skid or not.
enum TestAI:: { ... }	m_skid_probability_state
	This implements a simple finite state machine: it starts in NOT_YET.
const ItemState *	m_last_item_random
	The last item selected for collection, for which a probability was determined.
bool	m_really_collect_item
	True if m_last_item_random was randomly selected to be collected.
RandomGenerator	m_random_collect_item
	A random number generator for collecting items.
enum TestAI:: { ... }	m_point_selection_algorithm
	Determines the algorithm to use to select the point-to-aim-for There are three different Point Selection Algorithms:

Additional Inherited Members
Static Public Member Functions inherited from AIBaseController
static void	enableDebug ()
static void	setTestAI (int n)
static int	getTestAI ()
Protected Attributes inherited from AIBaseLapController
int	m_track_node
	The current node the kart is on.
LinearWorld *	m_world
	Keep a pointer to world.
std::vector< int >	m_successor_index
	Which of the successors of a node was selected by the AI.
std::vector< int >	m_next_node_index
	For each node in the graph this list contains the chosen next node.
std::vector< std::vector< int > >	m_all_look_aheads
	For each graph node this list contains a list of the next X graph nodes.
Protected Attributes inherited from AIBaseController
bool	m_enabled_network_ai
float	m_kart_length
	Length of the kart, storing it here saves many function calls.
float	m_kart_width
	Cache width of kart.
Track *	m_track
	Keep a pointer to the track to reduce calls.
const AIProperties *	m_ai_properties
	A pointer to the AI properties for this kart.
Protected Attributes inherited from Controller
AbstractKart *	m_kart
	Pointer to the kart that is controlled by this controller.
KartControl *	m_controls
	A pointer to the main controller, from which the kart takes it commands.
std::string	m_controller_name
	The name of the controller, mainly used for debugging purposes.
Static Protected Attributes inherited from AIBaseController
static bool	m_ai_debug = false
static int	m_test_ai = 0
	Stores the '–test-ai=n' command line parameter: It indicates which fraction of the AIs are going to be the test AI: 1 means only to use the TestAI, 2 means every second AI will be test etc.

Detailed Description

This is a test version of the AI, which can be used to create new AIs, and compare them with the current AI.

It is otherwise (at this stage) identical to the Skidding AI.

Member Enumeration Documentation

anonymous enum

anonymous enum

private

This implements a simple finite state machine: it starts in NOT_YET.

The first time the AI decides to skid, the state is changed randomly (depending on skid probability) to NO_SKID or SKID. As long as the AI keeps on deciding to skid, the state remains unchanged (so no new random decision is made) till it decides not to skid. In which case the state is set to NOT_YET again. This guarantees that for each 'skidable' section of the track the random decision is only done once.

anonymous enum

anonymous enum

private

Determines the algorithm to use to select the point-to-aim-for There are three different Point Selection Algorithms:

1. findNonCrashingPoint() is the default (which is actually slightly buggy, but so far best one after handling of 90 degree turns was added).
2. findNonCrashingPointFixed() which fixes the bugs of the default algorithm.
3. findNonCrashingPointNew() A newly designed algorithm, which is faster than the standard one, but does not give as good results as the 'buggy' one.

So far the default one has by far the best performance, even though it has bugs.

Member Function Documentation

canSkid()

virtual bool TestAI::canSkid ( float  steer_fraction )

privatevirtual

Return true if AI can skid now.

Implements AIBaseController.

getNextSector()

virtual unsigned int TestAI::getNextSector ( unsigned int  index )

protectedvirtual

Returns the next sector of the given sector index.

This is used for branches in the quad graph to select which way the AI kart should go. This is a very simple implementation that always returns the first successor, but it can be overridden to allow a better selection.

Parameters

index

Index of the graph node for which the successor is searched.

Returns

Returns the successor of this graph node.

Reimplemented from AIBaseLapController.

reset()

virtual void TestAI::reset ( )

virtual

Reimplemented from AIBaseLapController.

setSteering()

virtual void TestAI::setSteering ( float  angle, float  dt  )

privatevirtual

Converts the steering angle to a lr steering in the range of -1 to 1.

If the steering angle is too great, it will also trigger skidding. This function uses a 'time till full steer' value specifying the time it takes for the wheel to reach full left/right steering similar to player karts when using a digital input device. The parameter is defined in the kart properties and helps somewhat to make AI karts more 'pushable' (since otherwise the karts counter-steer to fast). It also takes the effect of a plunger into account by restricting the actual steer angle to 50% of the maximum.

Parameters

angle	Steering angle.
dt	Time step.

Reimplemented from AIBaseController.

update()

virtual void TestAI::update ( int  ticks )

virtual

Updates the ai base controller each time step.

Note that any calls to isStuck() must be done before update is called, since update will call AIBaseController::update() which will reset the isStuck flag!

Parameters

ticks

Number of physics time steps - should be 1.

Reimplemented from AIBaseLapController.

Member Data Documentation

m_avoid_item_close

bool TestAI::m_avoid_item_close

private

True if items to avoid are close by.

Used to avoid using zippers (which would make it more difficult to avoid items).

m_current_curve_radius

float TestAI::m_current_curve_radius

private

The radius of the curve the kart is currently driving.

Undefined when being on a straigt section.

m_kart_ahead

AbstractKart* TestAI::m_kart_ahead

private

Pointer to the closest kart ahead of this kart.

NULL if this kart is first.

m_kart_behind

AbstractKart* TestAI::m_kart_behind

private

Pointer to the closest kart behind this kart.

NULL if this kart is last.

m_last_direction_node

unsigned int TestAI::m_last_direction_node

private

The index of the last node with the same direction as the current node the kart is on.

If kart is in a left turn, this will be the last node that is still turning left etc.

enum { ... } TestAI::m_point_selection_algorithm

Determines the algorithm to use to select the point-to-aim-for There are three different Point Selection Algorithms:

1. findNonCrashingPoint() is the default (which is actually slightly buggy, but so far best one after handling of 90 degree turns was added).
2. findNonCrashingPointFixed() which fixes the bugs of the default algorithm.
3. findNonCrashingPointNew() A newly designed algorithm, which is faster than the standard one, but does not give as good results as the 'buggy' one.

So far the default one has by far the best performance, even though it has bugs.

enum { ... } TestAI::m_skid_probability_state

This implements a simple finite state machine: it starts in NOT_YET.

The first time the AI decides to skid, the state is changed randomly (depending on skid probability) to NO_SKID or SKID. As long as the AI keeps on deciding to skid, the state remains unchanged (so no new random decision is made) till it decides not to skid. In which case the state is set to NOT_YET again. This guarantees that for each 'skidable' section of the track the random decision is only done once.

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

• karts/controller/test_ai.hpp