A base class for AI that use navmesh to work. More...

#include <arena_ai.hpp>

Inheritance diagram for ArenaAI:

[legend]

Public Member Functions
	ArenaAI (AbstractKart *kart)

virtual void	update (int ticks) OVERRIDE
	This is the main entry point for the AI.

virtual void	reset () OVERRIDE
	Resets the AI when a race is restarted.

virtual void	newLap (int lap) OVERRIDE
	Callback whenever a new lap is triggered.

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
void	tryCollectItem (Vec3 aim_point, int target_node) const
	Try to collect item in arena, if no suitable item is found, like they are swapped, it will follow closest kart instead.

virtual void	findClosestKart (bool consider_difficulty, bool find_sta)=0
	Find the closest kart around this AI, implemented by sub-class.

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.

Protected Attributes
ItemManager *	m_item_manager

ArenaGraph *	m_graph
	Pointer to the ArenaGraph.

AbstractKart *	m_closest_kart
	Pointer to the closest kart around this kart.

int	m_closest_kart_node
	The ArenaNode at which the closest kart located on.

Vec3	m_closest_kart_point
	The closest kart location.

RaceManager::Difficulty	m_cur_difficulty
	Holds the current difficulty.

irr::scene::ISceneNode *	m_debug_sphere
	For debugging purpose: a sphere indicating where the AI is targeting at.

irr::scene::ISceneNode *	m_debug_sphere_next
	For debugging purpose: a sphere indicating where the first turning corner is located.

int	m_target_node
	The ArenaNode at which the target point located on.

Vec3	m_target_point
	The coordinates of target point.

bool	m_mini_skid
	True if AI can skid, currently only do when close to target, see doSkiddingTest().

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.

Private Member Functions
void	configSpeed ()
	Configure a suitable speed depends on current turn radius.

void	configSteering ()
	This function config the steering (m_steering_angle) of AI.

void	checkIfStuck (const float dt)
	Determine whether AI is stuck, by checking if it stays on the same node for a long period of time (see m_on_node), or isStuck() is true.

void	determinePath (int forward, std::vector< int > *path)
	Determine if the path to target needs to be changed to avoid bad items, it will also set the turn radius based on the new path if necessary.

void	doSkiddingTest ()
	Determine if AI should skid: When it's close to target, but not straight ahead, in front of it, same steering side and with suitable difficulties which are in expert and supertux only.

void	doUTurn (const float dt)
	Make AI reverse so that it faces in front of the last target point.

bool	gettingUnstuck (int ticks)
	Function to let AI get unstuck.

bool	updateAimingPosition (Vec3 *target_point)
	Update aiming position, use path finding if necessary.

void	useItems (const float dt)
	Determine how AI should use its item, different m_cur_difficulty will have a corresponding strategy.

virtual bool	canSkid (float steer_fraction) OVERRIDE
	Return true if AI can skid now.

virtual void	findTarget ()=0
	Find a suitable target for this frame, implemented by sub-class.

virtual bool	forceBraking ()
	If true, AI will always try to brake for this frame.

virtual int	getCurrentNode () const =0
	Return the current ArenaNode the AI located on.

virtual float	getKartDistance (const AbstractKart *kart) const =0
	Return the distance based on graph distance matrix to any kart.

virtual bool	ignorePathFinding ()
	If true, AI will drive directly to target without path finding.

virtual bool	isWaiting () const =0
	If true, AI will stop moving.

virtual bool	isKartOnRoad () const =0
	If true, AI stays on the ArenaNode correctly, otherwise RescueAnimation will be done after sometime.

virtual void	resetAfterStop ()
	Overridden if any action is needed to be done when AI stopped moving or changed driving direction.

Private Attributes
Vec3	m_target_point_lc
	Local coordinates of current target point.

Vec3	m_reverse_point
	Save the last target point before reversing, so AI will end reversing until facing in front of it.

bool	m_is_stuck
	Indicates that the kart is currently stuck, and m_ticks_since_reversing is counting down.

bool	m_is_uturn
	Indicates that the kart need a uturn to reach a node behind, and m_time_since_uturn is counting down.

std::set< int >	m_on_node
	Holds the unique node ai has driven through, useful to tell if AI is stuck by determine the size of this set.

float	m_time_since_last_shot
	Time an item has been collected and not used.

float	m_ticks_since_reversing
	This is a timer that counts down when the kart is reversing to get unstuck.

float	m_time_since_driving
	This is a timer that counts down when the kart is starting to drive.

float	m_time_since_uturn
	This is a timer that counts down when the kart is doing u-turn.

int	m_ticks_since_off_road
	This is a timer that counts when the kart start going off road.

float	m_turn_radius
	Used to determine braking and nitro usage.

float	m_steering_angle
	Used to determine if skidding can be done.

Vec3	m_current_forward_point
	The point in front of the AI which distance is m_kart_length, used to compensate the time difference between steering when finding next node.

int	m_current_forward_node
	The ArenaNode at which the forward point located on.

Additional Inherited Members
Static Public Member Functions inherited from AIBaseController
static void	enableDebug ()

static void	setTestAI (int n)

static int	getTestAI ()

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

A base class for AI that use navmesh to work.

Member Function Documentation

◆ canSkid()

virtual bool ArenaAI::canSkid ( float steer_fraction )

inlineprivatevirtual

Return true if AI can skid now.

Implements AIBaseController.

Reimplemented in SoccerAI.

◆ checkIfStuck()

void ArenaAI::checkIfStuck ( const float dt )

private

Determine whether AI is stuck, by checking if it stays on the same node for a long period of time (see m_on_node), or isStuck() is true.

Parameters

dt	Time step size.

Returns: True if AI is stuck

◆ determinePath()

void ArenaAI::determinePath	(	int	forward,
		std::vector< int > *	path
	)

private

Determine if the path to target needs to be changed to avoid bad items, it will also set the turn radius based on the new path if necessary.

Parameters

	forward	Forward node of current AI position.
[in,out]	path	Default path to follow, will be changed if needed.

◆ findClosestKart()

virtual void ArenaAI::findClosestKart	(	bool	consider_difficulty,
		bool	find_sta
	)

protectedpure virtual

Find the closest kart around this AI, implemented by sub-class.

Parameters

consider_difficulty	If take current difficulty into account.
find_sta	If find SpareTireAI only.

Implemented in BattleAI, and SoccerAI.

◆ findTarget()

virtual void ArenaAI::findTarget ( )

privatepure virtual

Find a suitable target for this frame, implemented by sub-class.

Implemented in BattleAI, SoccerAI, and SpareTireAI.

◆ forceBraking()

virtual bool ArenaAI::forceBraking ( )

inlineprivatevirtual

If true, AI will always try to brake for this frame.

Reimplemented in SoccerAI.

◆ getCurrentNode()

virtual int ArenaAI::getCurrentNode ( ) const

privatepure virtual

Return the current ArenaNode the AI located on.

Implemented in BattleAI, and SoccerAI.

◆ getKartDistance()

virtual float ArenaAI::getKartDistance ( const AbstractKart * kart ) const

privatepure virtual

Return the distance based on graph distance matrix to any kart.

Parameters

kart	AbstractKart to check.

Implemented in BattleAI, and SoccerAI.

◆ gettingUnstuck()

bool ArenaAI::gettingUnstuck ( int ticks )

private

Function to let AI get unstuck.

Parameters

dt	Time step size.

Returns: True if getting stuck is needed to be done.

◆ ignorePathFinding()

virtual bool ArenaAI::ignorePathFinding ( )

inlineprivatevirtual

If true, AI will drive directly to target without path finding.

Reimplemented in SoccerAI.

◆ isKartOnRoad()

virtual bool ArenaAI::isKartOnRoad ( ) const

privatepure virtual

If true, AI stays on the ArenaNode correctly, otherwise RescueAnimation will be done after sometime.

Implemented in BattleAI, and SoccerAI.

◆ isWaiting()

virtual bool ArenaAI::isWaiting ( ) const

privatepure virtual

If true, AI will stop moving.

Implemented in BattleAI, and SoccerAI.

◆ newLap()

virtual void ArenaAI::newLap ( int lap )

inlinevirtual

Callback whenever a new lap is triggered.

Used by the AI to trigger a recomputation of the way to use.

Implements Controller.

◆ reset()

void ArenaAI::reset ( )

virtual

Resets the AI when a race is restarted.

Reimplemented from AIBaseController.

Reimplemented in SoccerAI, and SpareTireAI.

◆ resetAfterStop()

virtual void ArenaAI::resetAfterStop ( )

inlineprivatevirtual

Overridden if any action is needed to be done when AI stopped moving or changed driving direction.

Reimplemented in SoccerAI.

◆ tryCollectItem()

void ArenaAI::tryCollectItem	(	Vec3 *	aim_point,
		int *	target_node
	)		const

protected

Try to collect item in arena, if no suitable item is found, like they are swapped, it will follow closest kart instead.

Parameters

[out]	aim_point	Location of item.
[out]	target_node	The node which item lied on.

◆ update()

void ArenaAI::update ( int ticks )

virtual

This is the main entry point for the AI.

It is called once per frame for each AI and determines the behaviour of the AI, e.g. steering, accelerating/braking, firing.

Parameters

ticks Number of physics time steps - should be 1.

Reimplemented from AIBaseController.

Reimplemented in SoccerAI, and SpareTireAI.

◆ updateAimingPosition()

bool ArenaAI::updateAimingPosition ( Vec3 * target_point )

private

Update aiming position, use path finding if necessary.

Parameters

[out] target_point Suitable target point.

Returns: True if found a suitable target point.

◆ useItems()

void ArenaAI::useItems ( const float dt )

private

Determine how AI should use its item, different m_cur_difficulty will have a corresponding strategy.

Parameters

dt	Time step size.

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

karts/controller/arena_ai.hpp
karts/controller/arena_ai.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ canSkid()

◆ checkIfStuck()

◆ determinePath()

◆ findClosestKart()

◆ findTarget()

◆ forceBraking()

◆ getCurrentNode()

◆ getKartDistance()

◆ gettingUnstuck()

◆ ignorePathFinding()

◆ isKartOnRoad()

◆ isWaiting()

◆ newLap()

◆ reset()

◆ resetAfterStop()

◆ tryCollectItem()

◆ update()

◆ updateAimingPosition()

◆ useItems()