Class for modelling game objects (players, enemies etc...) More...

#include <GameObject.h>

Inheritance diagram for ime::GameObject:

Public Types
using	Ptr = std::unique_ptr< GameObject >
	Unique game object pointer. More...

using	BodyPtr = std::unique_ptr< RigidBody >
	Unique Body pointer. More...

using	CollisionCallback = Callback< GameObject , GameObject >
	Collision callback. More...

Public Member Functions
	GameObject (Scene &scene)
	Constructor. More...

	GameObject (const GameObject &)
	Copy constructor. More...

GameObject &	operator= (const GameObject &)
	Copy assignment operator. More...

	GameObject (GameObject &&) noexcept
	Move constructor. More...

GameObject &	operator= (GameObject &&) noexcept
	Move assignment operator. More...

void	swap (GameObject &other)
	Swap the game object with another game object. More...

GameObject::Ptr	copy () const
	Create a copy of the game object. More...

void	setState (int state)
	Set current state. More...

int	getState () const
	Get the current state of the game object. More...

void	setActive (bool isActive)
	Set whether or not the game object is active. More...

bool	isActive () const
	Check if the game object is active or not. More...

PropertyContainer &	getUserData ()
	Get the user data added to game object. More...

const PropertyContainer &	getUserData () const

std::string	getClassName () const override
	Get the name of the class the game object is instantiated from. More...

std::string	getClassType () const override
	Get the name of this class. More...

void	attachRigidBody (BodyPtr body)
	Attach a physics Body to the game object. More...

RigidBody *	getRigidBody ()
	Get the game objects physics body. More...

const RigidBody *	getRigidBody () const

void	removeRigidBody ()
	Remove a rigid body from the game object. More...

bool	hasRigidBody () const
	Check if the the game object has a rigid body attached to it. More...

int	onRigidBodyCollisionStart (const CollisionCallback &callback, bool oneTime=false)
	Add an event listener to a rigid body collision begin event. More...

int	onRigidBodyCollisionEnd (const CollisionCallback &callback, bool oneTime=false)
	Add an event listener to a rigid body collision end event. More...

int	onRigidBodyCollisionStay (const CollisionCallback &callback, bool oneTime=false)
	Add an event listener to a rigid body collision stay event. More...

Transform &	getTransform ()
	Get the game objects transform. More...

const Transform &	getTransform () const

Scene &	getScene ()
	Get the scene the game object belongs to. More...

const Scene &	getScene () const

void	resetSpriteOrigin ()
	Reset the origin of the sprite. More...

Sprite &	getSprite ()
	Get the game objects graphical representation. More...

const Sprite &	getSprite () const

virtual void	update (Time deltaTime)
	Update the game object. More...

void	emitRigidBodyCollisionEvent (const std::string &event, GameObject *other)

	~GameObject () override
	Destructor. More...

void	setTag (const std::string &tag)
	Assign the object an alias. More...

const std::string &	getTag () const
	Get the tag assigned to the object. More...

unsigned int	getObjectId () const
	Get the unique id of the object. More...

int	onPropertyChange (const std::string &property, const Callback< Property > &callback, bool oneTime=false)
	Add an event listener to a specific property change event. More...

int	onPropertyChange (const Callback< Property > &callback, bool oneTime=false)
	Add an event listener to any property change event. More...

void	suspendedEventListener (int id, bool suspend)
	Pause or resume execution of an event listener. More...

bool	isEventListenerSuspended (int id) const
	Check if an event listener is suspended or not. More...

bool	removeEventListener (const std::string &event, int id)
	Remove an event listener from an event. More...

bool	removeEventListener (int id)
	Remove an event listener. More...

int	onDestruction (const Callback<> &callback)
	Add a destruction listener. More...

bool	isSameObjectAs (const Object &other) const
	Check if another object is the same instance as this object. More...

Static Public Member Functions
static GameObject::Ptr	create (Scene &scene)
	Create a new GameObject instance. More...

Protected Member Functions
void	emitChange (const Property &property)
	Dispatch a property change event. More...

void	emitDestruction ()
	Emit a destruction event. More...

Protected Attributes
EventEmitter	eventEmitter_
	Event dispatcher. More...

Detailed Description

Class for modelling game objects (players, enemies etc...)

Definition at line 42 of file GameObject.h.

Member Typedef Documentation

◆ BodyPtr

using ime::GameObject::BodyPtr = std::unique_ptr<RigidBody>

Unique Body pointer.

Definition at line 45 of file GameObject.h.

◆ CollisionCallback

using ime::GameObject::CollisionCallback = Callback<GameObject*, GameObject*>

Collision callback.

Definition at line 46 of file GameObject.h.

◆ Ptr

using ime::GameObject::Ptr = std::unique_ptr<GameObject>

Unique game object pointer.

Definition at line 44 of file GameObject.h.

Constructor & Destructor Documentation

◆ GameObject() [1/3]

ime::GameObject::GameObject ( Scene & scene )

explicit

Constructor.

Parameters

scene The scene this game object belongs to

◆ GameObject() [2/3]

ime::GameObject::GameObject ( const GameObject & )

Copy constructor.

◆ GameObject() [3/3]

ime::GameObject::GameObject ( GameObject && )

noexcept

Move constructor.

◆ ~GameObject()

ime::GameObject::~GameObject ( )

override

Destructor.

Member Function Documentation

◆ attachRigidBody()

void ime::GameObject::attachRigidBody ( BodyPtr body )

Attach a physics Body to the game object.

Parameters

body	Physics body to be attached to the game object

When a rigid body is attached to a game object, the game object becomes enabled for physics. This means that it will react to gravity, friction, applies forces, impulses etc. The position and rotation of the game object will be controlled by the physics engine therefore you should refrain from calling functions that MODIFY the game objects transform (position, rotation and origin). A result of doing so is inconsistency. Note that the physics engine does not account for scaling. This means that scaling the objects sprite will NOT scale the objects body or the body's collider. If you want the body to scale with the objects sprite, you should remove the old collider and attach a new one with the appropriate size.

Warning: The pointer must not be a nullptr. Also, you cannot attach a rigid body to a game object that already has a rigid body attached to it, the current rigid body must be removed first

See also: removeRigidBody

◆ copy()

GameObject::Ptr ime::GameObject::copy ( ) const

Create a copy of the game object.

Returns: A new game object

◆ create()

static GameObject::Ptr ime::GameObject::create ( Scene & scene )

static

Create a new GameObject instance.

Parameters

scene The scene the object belongs to

Returns: The created instance

◆ emitChange()

void ime::Object::emitChange ( const Property & property )

protectedinherited

Dispatch a property change event.

Parameters

property The property that changed

This function will invoke all the event listeners of the specified property

See also: emit

◆ emitDestruction()

void ime::Object::emitDestruction ( )

protectedinherited

Emit a destruction event.

Note: This function must be the first statement in the definition of a destructor to avoid undefined behavior. In addition, note that destruction listeners are invoked once. Therefore, multiple classes in a hierarchy may call this function but the class that makes the call first will be the one that invokes the destruction listeners

◆ getClassName()

std::string ime::GameObject::getClassName ( ) const

overridevirtual

Get the name of the class the game object is instantiated from.

Returns: The name of the concrete class the game object is instantiated from

Note that this function must be overridden further if this class is extended, otherwise it will return the name of this class instead of your class name

See also: getClassType

Implements ime::Object.

Reimplemented in ime::GridObject.

◆ getClassType()

std::string ime::GameObject::getClassType ( ) const

overridevirtual

Get the name of this class.

Returns: The name of this class

Note that this function is only implemented by child classes of Object which also serve as a base class for other classes

See also: getClassName

Reimplemented from ime::Object.

◆ getObjectId()

unsigned int ime::Object::getObjectId ( ) const

inherited

Get the unique id of the object.

Returns: The unique id of the object

Note that each instance of ime::Object has a unique id

See also: setTag

◆ getRigidBody()

RigidBody * ime::GameObject::getRigidBody ( )

Get the game objects physics body.

Returns: The game objects physics body if any, otherwise a nullptr

◆ getScene()

Scene & ime::GameObject::getScene ( )

Get the scene the game object belongs to.

Returns: The scene the game object belongs to

◆ getSprite()

Sprite & ime::GameObject::getSprite ( )

Get the game objects graphical representation.

Returns: The game objects graphical representation

By default, the sprite is empty

◆ getState()

int ime::GameObject::getState ( ) const

Get the current state of the game object.

Returns: The current state of the game object

◆ getTag()

const std::string & ime::Object::getTag ( ) const

inherited

Get the tag assigned to the object.

Returns: The tag of the object

See also: setTag

◆ getTransform()

Transform & ime::GameObject::getTransform ( )

Get the game objects transform.

Returns: The game objects transform

The transform can be used to query or modify the game object position, scale, rotation and origin

◆ getUserData()

PropertyContainer & ime::GameObject::getUserData ( )

Get the user data added to game object.

Returns: The user data

The user data object can be used to store additional information about the game object. For example, you may store a profile associated with the game object or when the game object was instantiated etc... You can store any type and any number of data in the user date object

Note that IME does not store anything inside the user data object, it is reserved for external use only

◆ hasRigidBody()

bool ime::GameObject::hasRigidBody ( ) const

Check if the the game object has a rigid body attached to it.

Returns: True if the game object has a rigid body attached to it, otherwise false

◆ isActive()

bool ime::GameObject::isActive ( ) const

Check if the game object is active or not.

Returns: True if the game object is active, otherwise false

See also: setActive

◆ isEventListenerSuspended()

bool ime::Object::isEventListenerSuspended ( int id ) const

inherited

Check if an event listener is suspended or not.

Parameters

id	The identification number of the listener to be checked

Returns: True if suspended, otherwise false

This function also returns false if the specified event listener does not exist

See also: suspendedEventListener

◆ isSameObjectAs()

bool ime::Object::isSameObjectAs ( const Object & other ) const

inherited

Check if another object is the same instance as this object.

Parameters

other The object to compare against this object

Returns: True if other is the same instance as this object, otherwise false

◆ onDestruction()

int ime::Object::onDestruction ( const Callback<> & callback )

inherited

Add a destruction listener.

Parameters

callback Function to be executed when the object is destroyed

Returns: The unique id of the destruction listener

The destruction listener is called when the object reaches the end of its lifetime. Note that an object may have multiple destruction listeners registered to it

Warning: It's not advised to call virtual functions in the destruction callback as some parts of the object may have already been destroyed by the time the callback is invoked. In such an event, the behavior is undefined

See also: removeEventListener

◆ onPropertyChange() [1/2]

int ime::Object::onPropertyChange	(	const Callback< Property > &	callback,
		bool	oneTime = `false`
	)

inherited

Add an event listener to any property change event.

Parameters

callback	The function to be executed when any property changes
oneTime	True to execute the callback one-time or false to execute it every time the event is triggered

Returns: The unique id of the event listener

When unsubscribing the any property change event handler, you must pass "propertyChange" as the name of the event

See also: onPropertyChange(const std::string&, const ime::Callback<ime::Property>&)

◆ onPropertyChange() [2/2]

int ime::Object::onPropertyChange	(	const std::string &	property,
		const Callback< Property > &	callback,
		bool	oneTime = `false`
	)

inherited

Add an event listener to a specific property change event.

Parameters

property	The name of the property to add an event listener to
oneTime	True to execute the callback one-time or false to execute it every time the event is triggered
callback	The function to be executed when the property changes

Returns: The unique id of the event listener

A property change event is triggered by any function that begins with set, where the the text after set is the name of the property. For example, the setTag() function, modifies the tag property of the object, thus will generate a "tag" change event each time it is called

Note that multiple event listeners may be registered to the same property change event. In addition, when adding a property change event listener, the name of the property must be in lowercase.

// Prints the tag of the player object to the console everytime it changes
player.onPropertyChange("tag", [](const Property& property) {
     cout << "New tag: " <<  property.getValue<std::string>() << endl;
});
 
...
//Sets tag = "player1" and invokes event listener(s)
player.setTag("player1");

See also: unsubscribe and onPropertyChange(const ime::Callback<ime::Property>&)

◆ onRigidBodyCollisionEnd()

int ime::GameObject::onRigidBodyCollisionEnd	(	const CollisionCallback &	callback,
		bool	oneTime = `false`
	)

Add an event listener to a rigid body collision end event.

Parameters

callback	The function to be executed when the event is fired
oneTime	True to execute the callback one-time or false to execute it every time the event is triggered

Returns: The event listeners identification number

The callback function is called when two game objects stop overlapping. The callback is passed this game object and the game object that stopped overlapping with this game object respectively.

A collision end handler may be registered on the game object or on the collider that is attached to the game objects rigid body or on both. However, exercise caution as registering the same handler on both objects will result in the handler being executed twice each time the event is fired

Note: A collision end event can only occur if the game object has a rigid body attached to it and the rigid body has a Collider attached to it

See also: attachRigidBody, onCollisionStart and onCollisionStay

◆ onRigidBodyCollisionStart()

int ime::GameObject::onRigidBodyCollisionStart	(	const CollisionCallback &	callback,
		bool	oneTime = `false`
	)

Add an event listener to a rigid body collision begin event.

Parameters

callback	The function to be executed when the event is fired
oneTime	True to execute the callback one-time or false to execute it every time the event is triggered

Returns: The event listeners identification number

The callback function is called when two game objects begin to overlap. The callback is passed this game object and the game object that collided with this game object respectively.

A collision begin handler may be registered on the game object or on the collider that is attached to the game objects rigid body or on both. However, exercise caution as registering the same handler on both objects will result in the handler being executed twice each time the event is fired

Note: A collision begin event can only occur if the game object has a rigid body attached to it and the rigid body has a Collider attached to it

See also: attachRigidBody, onCollisionStay and onCollisionEnd

◆ onRigidBodyCollisionStay()

int ime::GameObject::onRigidBodyCollisionStay	(	const CollisionCallback &	callback,
		bool	oneTime = `false`
	)

Add an event listener to a rigid body collision stay event.

Parameters

callback	The function to be executed when the event is fired
oneTime	True to execute the callback one-time or false to execute it every time the event is triggered

Returns: The event listeners identification number

The callback function is called while this game object remains in contact with another game object. The callback is passed this game object and the game object that is currently in contact with this game object respectively.

A collision stay handler may be registered on the game object or on the collider that is attached to the game objects rigid body or on both. However, exercise caution as registering the same handler on both objects will result in the handler being executed twice each time the event is fired

Note: A collision stay event can only occur if the game object has a rigid body attached to it and the rigid body is awake and has a Collider attached to it that is not a sensor

See also: attachRigidBody, onCollisionStart and onCollisionEnd

◆ operator=() [1/2]

GameObject & ime::GameObject::operator= ( const GameObject & )

Copy assignment operator.

◆ operator=() [2/2]

GameObject & ime::GameObject::operator= ( GameObject && )

noexcept

Move assignment operator.

◆ removeEventListener() [1/2]

bool ime::Object::removeEventListener	(	const std::string &	event,
		int	id
	)

inherited

Remove an event listener from an event.

Parameters

event	The name of the event to remove an event listener from
id	The unique id of the event listener to be removed

Returns: True if the event listener was removed or false if the event or the event listener is does not exist

// Display the tag of the object to console every time it changes
auto tagChangeId = object.onPropertyChange("tag", [](ime::Property tag) {
     std::cout << name.getValue<std::string>() << std::endl;
});
 
// Stop displaying the tag of the object when it changes
object.removeEventListener("tag", tagChangeId);

◆ removeEventListener() [2/2]

bool ime::Object::removeEventListener ( int id )

inherited

Remove an event listener.

Parameters

id	The id of the event listener to be removed

Returns: True if the event listener was removed or false if no such handler exists

◆ removeRigidBody()

void ime::GameObject::removeRigidBody ( )

Remove a rigid body from the game object.

Removing a rigid Body from an game object disables all physics applied to it

See also: attachRigidBody

◆ resetSpriteOrigin()

void ime::GameObject::resetSpriteOrigin ( )

Reset the origin of the sprite.

The origin is reset to the local centre of the sprite

Note: This function must be called everytime the sprites texture, texture rectangle size or scale is changed

◆ setActive()

void ime::GameObject::setActive ( bool isActive )

Set whether or not the game object is active.

Parameters

isActive True to set as active or false to set as inactive

Note that an inactive game object does not participate in collision detection. In addition the game object's update() method will not be invoked.

By default, the object is active

See also: isActive

◆ setState()

void ime::GameObject::setState ( int state )

Set current state.

Parameters

state The current state

The state is number that should be associated with something (maybe an enum) in your game.

Be default, the state is -1, which is supposed to indicate that there is no state. The state property is optional and may be used if needs be. It is not used by IME

◆ setTag()

void ime::Object::setTag ( const std::string & tag )

inherited

Assign the object an alias.

Parameters

tag	The alias of the object

This function is useful if you want to refer to the object by a tag instead of its object id. Unlike an object id, multiple objects may have the same tag

By default, the tag is an empty string

See also: getObjectId

◆ suspendedEventListener()

void ime::Object::suspendedEventListener	(	int	id,
		bool	suspend
	)

inherited

Pause or resume execution of an event listener.

Parameters

id	The event listeners unique identification number
suspend	True to suspend/pause or false to unsuspend/resume

See also: isEventListenerSuspended

◆ swap()

void ime::GameObject::swap ( GameObject & other )

Swap the game object with another game object.

Parameters

other The game object to swap with this game object

◆ update()

virtual void ime::GameObject::update ( Time deltaTime )

inlinevirtual

Update the game object.

Parameters

deltaTime Time past since last update

This function is automatically called by IME. deltaTime is synced with the render FPS. In other words, it is frame-rate dependent.

Note that this function is provided for external use only, IME will never put anything inside it. This means that don't have to call the base class version when overriding it

Definition at line 346 of file GameObject.h.

Member Data Documentation

◆ eventEmitter_

EventEmitter ime::Object::eventEmitter_

protectedinherited

Event dispatcher.

Definition at line 289 of file Object.h.

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

GameObject.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ BodyPtr

◆ CollisionCallback

◆ Ptr

Constructor & Destructor Documentation

◆ GameObject() [1/3]

◆ GameObject() [2/3]

◆ GameObject() [3/3]

◆ ~GameObject()

Member Function Documentation

◆ attachRigidBody()

◆ copy()

◆ create()

◆ emitChange()

◆ emitDestruction()

◆ getClassName()

◆ getClassType()

◆ getObjectId()

◆ getRigidBody()

◆ getScene()

◆ getSprite()

◆ getState()

◆ getTag()

◆ getTransform()

◆ getUserData()

◆ hasRigidBody()

◆ isActive()

◆ isEventListenerSuspended()

◆ isSameObjectAs()

◆ onDestruction()

◆ onPropertyChange() [1/2]

◆ onPropertyChange() [2/2]

◆ onRigidBodyCollisionEnd()

◆ onRigidBodyCollisionStart()

◆ onRigidBodyCollisionStay()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ removeEventListener() [1/2]

◆ removeEventListener() [2/2]

◆ removeRigidBody()

◆ resetSpriteOrigin()

◆ setActive()

◆ setState()

◆ setTag()

◆ suspendedEventListener()

◆ swap()

◆ update()

Member Data Documentation

◆ eventEmitter_