A 2D camera that defines what region is shown on screen in a Scene. More...

#include <Camera.h>

Inheritance diagram for ime::Camera:

Public Types
using	Ptr = std::shared_ptr< Object >
	Shared object pointer. More...

Public Member Functions
	Camera (Camera &&)=delete
	Move constructor. More...

Camera &	operator= (Camera &&)=delete
	Move assignment operator. More...

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

void	setCenter (float x, float y)
	Set the centre of the camera. More...

void	setCenter (const Vector2f &centre)
	Set the centre of the camera. More...

Vector2f	getCenter () const
	Get the centre of the camera. More...

void	setSize (float width, float height)
	Set the size of the camera. More...

void	setSize (const Vector2f &size)
	Set the size of the camera. More...

Vector2f	getSize () const
	Get the size of the camera. More...

void	setRotation (float angle)
	Set the orientation of the camera. More...

float	getRotation () const
	Get the current orientation of the camera. More...

void	setViewport (const FloatRect &viewport)
	Set the target viewport. More...

FloatRect	getViewport () const
	Get the target viewport of the rectangle of the camera. More...

void	reset (const FloatRect &rectangle)
	Reset the camera to the given rectangle. More...

void	resetToDefault ()
	Reset the camera to its default settings. More...

void	move (float offsetX, float offsetY)
	Move the camera relative to its current position. More...

void	move (const Vector2f &offset)
	Move the camera relative to its current position. More...

void	rotate (float angle)
	Rotate the camera relative to its current orientation. More...

void	zoom (float factor)
	Resize the camera rectangle relative to its current size. More...

Vector2f	windowCoordToWorldCoord (const Vector2i &point) const
	Convert a window coordinate to a world coordinate. More...

Vector2i	worldCoordToWindowCoord (const Vector2f &point) const
	Convert a world coordinate to a window coordinate. More...

	~Camera () override
	Destructor. More...

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

const std::string &	getTag () const
	Get the alias of the object. More...

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

virtual std::string	getClassType () const
	Get the name of the direct parent of an object instance. More...

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

void	onPropertyChange (const Callback< Property > &callback)
	Add an event listener to a property change event. More...

int	onEvent (const std::string &event, const Callback<> &callback)
	Add an event listener to an event. More...

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

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

bool	removeDestructionListener (int id)
	Remove a destruction listener form the object. More...

bool	operator== (const Object &rhs) const
	Check if two objects are the same object or not. More...

bool	operator!= (const Object &rhs) const
	Check if two objects are not the same object. More...

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

void	emit (const std::string &event)
	Dispatch an action event. More...

Friends
class	Scene
	Needs access to constructor. More...

Detailed Description

A 2D camera that defines what region is shown on screen in a Scene.

A camera is composed of a source rectangle, which defines what part of the Scene is shown, and a target viewport, which defines where the contents of the source rectangle will be displayed on the render Window.

The viewport allows to map the scene to a custom part of the render window, and can be used for split-screen or for displaying a minimap, for example. If the source rectangle doesn't have the same size as the viewport, its contents will be stretched to fit in

You do not instantiate a camera directly, it is created when you instantiate a scene and it is accessible within the scene. Each scene instance has its own camera

Definition at line 54 of file Camera.h.

Member Typedef Documentation

◆ Ptr

using ime::Object::Ptr = std::shared_ptr<Object>

inherited

Shared object pointer.

Definition at line 45 of file Object.h.

Constructor & Destructor Documentation

◆ Camera()

ime::Camera::Camera ( Camera && )

delete

Move constructor.

◆ ~Camera()

ime::Camera::~Camera ( )

override

Destructor.

Member Function Documentation

◆ emit()

void ime::Object::emit ( const std::string & event )

protectedinherited

Dispatch an action event.

Parameters

event The name of the event to be dispatched

This function will invoke all event listeners of the specified event. The function should be used for events that represent an action, rather than those that represent a property change (Use emitChange for that)

See also: emitChange

◆ 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

◆ getCenter()

Vector2f ime::Camera::getCenter ( ) const

Get the centre of the camera.

Returns: The centre of the camera

◆ getClassName()

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

overridevirtual

Get the name of this class.

Returns: The name of this class

Implements ime::Object.

◆ getClassType()

virtual std::string ime::Object::getClassType ( ) const

virtualinherited

Get the name of the direct parent of an object instance.

Returns: The name of the direct parent of an object instance

In contrast to getClassName which returns the name of the concrete class, this function returns the name of the concrete class's base class. This function is implemented by all derived classes of Object which also serve as base classes for other Objects. For classes whose direct parent is this class, this function will return the name of this class

auto rectangle = ime::RectangleShape(); // RectangleShape is derived from Shape
std::cout << rectangle->getClassName(); // Prints "RectangleShape"
std::cout << rectangle->getClassType(); // Prints "Shape"

See also: getClassName

Reimplemented in ime::SpriteImage, ime::Shape, ime::Drawable, ime::GridMover, ime::Joint, ime::Collider, and ime::GameObject.

◆ getObjectId()

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

inherited

Get the id of the object.

Returns: The id of the object

Each object has a unique id

◆ getRotation()

float ime::Camera::getRotation ( ) const

Get the current orientation of the camera.

Returns: The rotation of the camera in degrees

◆ getSize()

Vector2f ime::Camera::getSize ( ) const

Get the size of the camera.

Returns: The size of the camera

◆ getTag()

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

inherited

Get the alias of the object.

Returns: The alias of the object

See also: setTag and getObjectId

◆ getViewport()

FloatRect ime::Camera::getViewport ( ) const

Get the target viewport of the rectangle of the camera.

Returns: The viewport rectangle, expressed as a factor of the target size

See also: setViewPort

◆ move() [1/2]

void ime::Camera::move ( const Vector2f & offset )

Move the camera relative to its current position.

Parameters

offset The move offset

◆ move() [2/2]

void ime::Camera::move	(	float	offsetX,
		float	offsetY
	)

Move the camera relative to its current position.

Parameters

offsetX	The value of the horizontal move offset
offsetY	The value of the vertical move offset

◆ 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 id of the destruction listener

Note that an object may have more than one destruction listeners, however, you have to keep the returned id if you may want to remove the callback at a later time

Warning: The callback is called when the object is destroyed. Do not try to access the object in the callback. Doing so is undefined behavior

See also: removeDestructionListener

◆ onEvent()

int ime::Object::onEvent	(	const std::string &	event,
		const Callback<> &	callback
	)

inherited

Add an event listener to an event.

Parameters

event	The name of the event to add an an event listener to
callback	The function to be executed when the event takes place

Returns: The unique identification number of the event listener

Unlike onPropertyChange, this function registers event listeners to events that occur when something happens to the object, or when the object does something (action events). Usually the name of the event/action is the name of the function:

// Add event listeners to the object
object.onEvent("attachRigidBody", [] {
    std::cout << "Rigid body attached to object << std::endl;
});
 
object.onEvent("removeRigidBody", [] {
    std::cout << "Rigid body removed from object << std::endl;
});
 
// Invokes event listener(s)
object.attachRigidBody(body);
object.removeRigidBody();

See also: onPropertyChange and unsubscribe

◆ onPropertyChange() [1/2]

void ime::Object::onPropertyChange ( const Callback< Property > & callback )

inherited

Add an event listener to a property change event.

Parameters

callback The function to be executed when the property changes

Returns: The unique id of the event listener

Note that only one callback function may be registered with this function. This means that adding a new event listener overwrites the previous event listener. To remove the callback, pass a nullptr as an argument. The function may be useful if you want to write the logic for property changes in one function.

See also: onPropertyChange(std::string, Callback)

◆ onPropertyChange() [2/2]

int ime::Object::onPropertyChange	(	const std::string &	property,
		const Callback< Property > &	callback
	)

inherited

Add an event listener to a specific property change event.

Parameters

property	The name of the property to listen for
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, for the setTag function, the property that the function modifies is Tag.

Note that 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");

Unlike onPropertyChange(const Callback&) you can add multiple event listeners to the same property using this function. However you must store the unique id of the event listener if you wish to remove it at a later time

See also: unsubscribe and onPropertyChange(Callback)

◆ operator!=()

bool ime::Object::operator!= ( const Object & rhs ) const

inherited

Check if two objects are not the same object.

Parameters

rhs	Object to compare against this object

Returns: True if rhs is NOT the same object as this object, otherwise false

Two objects are different from each other if they have different object id's

See also: getObjectId and operator==

◆ operator=()

Camera& ime::Camera::operator= ( Camera && )

delete

Move assignment operator.

◆ operator==()

bool ime::Object::operator== ( const Object & rhs ) const

inherited

Check if two objects are the same object or not.

Parameters

rhs	Object to compare against this object

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

Two objects are the same object if they have the same object id. Recall that each object instance has a unique id

See also: getObjectId and operator!=

◆ removeDestructionListener()

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

inherited

Remove a destruction listener form the object.

Parameters

The	id of the destruction listener to be removed

Returns: True if the destruction listener was removed or false if the listener with the given id does not exist

◆ reset()

void ime::Camera::reset ( const FloatRect & rectangle )

Reset the camera to the given rectangle.

Parameters

rectangle Rectangle defining the zone to display

Note: This function resets the rotation of the camera to 0 degrees

◆ resetToDefault()

void ime::Camera::resetToDefault ( )

Reset the camera to its default settings.

◆ rotate()

void ime::Camera::rotate ( float angle )

Rotate the camera relative to its current orientation.

Parameters

angle The angle to rotate the camera by in degrees

See also: setRotation

◆ setCenter() [1/2]

void ime::Camera::setCenter ( const Vector2f & centre )

Set the centre of the camera.

Parameters

centre The new centre of the camera

◆ setCenter() [2/2]

void ime::Camera::setCenter	(	float	x,
		float	y
	)

Set the centre of the camera.

Parameters

x	X coordinate of the new centre
y	Y coordinate of the new centre

◆ setRotation()

void ime::Camera::setRotation ( float angle )

Set the orientation of the camera.

Parameters

angle The orientation to set in degrees

By default, the rotation is 0 degrees

◆ setSize() [1/2]

void ime::Camera::setSize ( const Vector2f & size )

Set the size of the camera.

Parameters

size	The new size of the camera

By default, the camera is the same size as the render window

◆ setSize() [2/2]

void ime::Camera::setSize	(	float	width,
		float	height
	)

Set the size of the camera.

Parameters

width	The new width of the camera
height	The new height of the camera

By default, the camera is the same size as the render window

◆ setTag()

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

inherited

Assign the object an alias.

Parameters

name	The alias of the object

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

By default, the tag is an empty string

◆ setViewport()

void ime::Camera::setViewport ( const FloatRect & viewport )

Set the target viewport.

Parameters

viewport The new viewport rectangle

The viewport is the rectangle into which the contents of the camera are displayed, expressed as a factor (between 0 and 1) of the size of the RenderWindow. For example, a view which takes the left side of the target would be defined with View.setViewport(sf::FloatRect(0, 0, 0.5, 1)).

By default, a camera has a viewport which covers the entire render window

◆ unsubscribe()

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

inherited

Remove an event listener from an event.

Parameters

event	The name of the event to remove 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 name of the object to console every time it changes
auto nameChangeId = object.onPropertyChange("name", [](Property name) {
     std::cout << name.getValue<std::string>() << std::endl;
});
 
// Stop displaying the name of the object when it changes
object.unsubscribe("name", id);

◆ windowCoordToWorldCoord()

Vector2f ime::Camera::windowCoordToWorldCoord ( const Vector2i & point ) const

Convert a window coordinate to a world coordinate.

Parameters

point The window coordinate to be converted

Returns: The converted point in world coordinates

Initially, both coordinate systems (world coordinates and window pixels) match perfectly. But if you move or rotate the camera or resize the render Window then a mismatch occurs, i.e. a point located at (10, 50) on the render Window may map to the point (150, 75) in your 2D world – if the camera is translated by (140, 25)

◆ worldCoordToWindowCoord()

Vector2i ime::Camera::worldCoordToWindowCoord ( const Vector2f & point ) const

Convert a world coordinate to a window coordinate.

Parameters

point The world point ot be converted

Returns: The converted point in window coordinates

Initially, both coordinate systems (world coordinates and window pixels) match perfectly. But if you move or rotate the camera or resize the render Window then a mismatch occurs, i.e. a point located at (10, 50) on the render Window may map to the point (150, 75) in your 2D world – if the camera is translated by (140, 25)

◆ zoom()

void ime::Camera::zoom ( float factor )

Resize the camera rectangle relative to its current size.

Parameters

factor The zoom factor to apply

Resizing the view simulates a zoom, as the zone displayed on screen grows or shrinks. factor is a multiplier:

1 keeps the size unchanged
> 1 makes the view bigger (objects appear smaller)
< 1 makes the view smaller (objects appear bigger)

See also: setSize

Friends And Related Function Documentation

◆ Scene

friend class Scene

friend

Needs access to constructor.

Definition at line 244 of file Camera.h.

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

Camera.h

Public Types

Public Member Functions

Protected Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ Ptr

Constructor & Destructor Documentation

◆ Camera()

◆ ~Camera()

Member Function Documentation

◆ emit()

◆ emitChange()

◆ getCenter()

◆ getClassName()

◆ getClassType()

◆ getObjectId()

◆ getRotation()

◆ getSize()

◆ getTag()

◆ getViewport()

◆ move() [1/2]

◆ move() [2/2]

◆ onDestruction()

◆ onEvent()

◆ onPropertyChange() [1/2]

◆ onPropertyChange() [2/2]

◆ operator!=()

◆ operator=()

◆ operator==()

◆ removeDestructionListener()

◆ reset()

◆ resetToDefault()

◆ rotate()

◆ setCenter() [1/2]

◆ setCenter() [2/2]

◆ setRotation()

◆ setSize() [1/2]

◆ setSize() [2/2]

◆ setTag()

◆ setViewport()

◆ unsubscribe()

◆ windowCoordToWorldCoord()

◆ worldCoordToWindowCoord()

◆ zoom()

Friends And Related Function Documentation

◆ Scene