wPlot2D::LegendEntity Class Reference

Represents a legend box that describes functions and data plots. More...

#include <wLegendEntity.hpp>

Inheritance diagram for wPlot2D::LegendEntity:

Public Member Functions
	LegendEntity (const sf::Font &font, const sf::Vector2f &position, bool hasFrame=true)
	Constructs a LegendEntity.
virtual	~LegendEntity ()=default
	Virtual destructor.
void	addItem (const std::string &label, FunctionEntity *function)
	Adds a new legend item associated with a function.
void	addItem (const std::wstring &label, FunctionEntity *function)
	Adds a new legend item associated with a function (wide string).
void	addItem (const std::string &label, DataPlotEntity *plot)
	Adds a new legend item associated with a data plot.
void	addItem (const std::wstring &label, DataPlotEntity *plot)
	Adds a new legend item associated with a data plot (wide string).
void	setFrameEnabled (bool enabled)
	Enables or disables the surrounding frame of the legend.
void	setFrameFillColor (const sf::Color &color)
	Sets the fill color of the legend frame.
void	setFrameOutlineColor (const sf::Color &color)
	Sets the outline color of the legend frame.
void	setFrameThickness (float thickness)
	Sets the outline thickness of the legend frame.
void	setPadding (const sf::Vector2f &padding)
	Sets the internal padding between items and the frame borders.
void	setFont (const sf::Font &font)
	Updates the font used for all legend labels.
void	setCharacterSize (unsigned int size)
	Sets the character size of the legend text.
void	setTextColor (const sf::Color &color)
	Sets the color of the legend labels.
void	render (sf::RenderWindow &window)
	Renders the legend (all items and optional frame) to the target window.
Public Member Functions inherited from wEngine::Entity
	Entity ()
virtual	~Entity ()
unsigned int	getEntityID () const
	Returns the unique ID associated with this entity.
void	clearComponents ()
	Removes all components currently attached to the entity.
template<typename T, typename... Args>
std::shared_ptr< T >	addComponent (Args &&... args)
	Adds a new component of type T to the entity.
template<typename T>
void	removeComponent ()
	Removes the component of type T from the entity.
template<typename T>
bool	hasComponent () const noexcept
	Checks whether the entity has a component of type T.
template<typename T>
std::shared_ptr< T >	getComponent () const
	Retrieves the component of type T attached to the entity.
template<typename T>
std::shared_ptr< T >	requireComponent (const std::string &context="") const
	Retrieves the component of type T and throws if it's missing.
template<typename Interface>
std::shared_ptr< Interface >	getInterfaceComponent () const
	Returns the first component that implements the specified interface.

Additional Inherited Members
Static Public Member Functions inherited from wEngine::Entity
static void	resetEntityIDCounter ()
	Resets the global entity ID counter to zero.

Detailed Description

Represents a legend box that describes functions and data plots.

A LegendEntity provides a visual legend for plotted entities such as FunctionEntity and DataPlotEntity. Each legend item is composed of:

• A sample line (LineEntity) with the same style, thickness, and color as the source entity.
• A text label (sf::Text) describing the entity.

The legend can optionally be surrounded by a frame (FrameEntity) with configurable padding, outline color, thickness, and fill color.

Components and Features:

• Configurable font and text size.
• Support for UTF-8 and wide string labels.
• Dynamic addition of items from existing plotted entities.
• Automatic alignment of line + text pairs inside the legend box.

See also

FunctionEntity, DataPlotEntity, LineEntity, FrameEntity

Note

The font passed in the constructor must remain valid during the lifetime of the legend, as SFML does not copy font data internally.

Author

Wilfried Koch

Copyright

© 2025 Wilfried Koch

Constructor & Destructor Documentation

LegendEntity()

wPlot2D::LegendEntity::LegendEntity	(	const sf::Font &	font,
		const sf::Vector2f &	position,
		bool	hasFrame = true )

Constructs a LegendEntity.

Initializes the legend with a given font, anchor position, and optional frame.

Parameters

font	Reference to the font used for labels (must remain valid).
position	Anchor position of the legend box in window coordinates.
hasFrame	Whether to display a surrounding frame (default: true).

~LegendEntity()

virtual wPlot2D::LegendEntity::~LegendEntity ( )

virtualdefault

Virtual destructor.

Member Function Documentation

addItem() [1/4]

void wPlot2D::LegendEntity::addItem	(	const std::string &	label,
		FunctionEntity *	function )

Adds a new legend item associated with a function.

Parameters

label	Label text (UTF-8 string).
function	Pointer to the source FunctionEntity.

addItem() [2/4]

void wPlot2D::LegendEntity::addItem	(	const std::wstring &	label,
		FunctionEntity *	function )

Adds a new legend item associated with a function (wide string).

Parameters

label	Label text (wide string).
function	Pointer to the source FunctionEntity.

addItem() [3/4]

void wPlot2D::LegendEntity::addItem	(	const std::string &	label,
		DataPlotEntity *	plot )

Adds a new legend item associated with a data plot.

Parameters

label	Label text (UTF-8 string).
plot	Pointer to the source DataPlotEntity.

addItem() [4/4]

void wPlot2D::LegendEntity::addItem	(	const std::wstring &	label,
		DataPlotEntity *	plot )

Adds a new legend item associated with a data plot (wide string).

Parameters

label	Label text (wide string).
plot	Pointer to the source DataPlotEntity.

setFrameEnabled()

void wPlot2D::LegendEntity::setFrameEnabled

(

bool

enabled

)

Enables or disables the surrounding frame of the legend.

Parameters

enabled

True to display the frame, false to hide it.

setFrameFillColor()

void wPlot2D::LegendEntity::setFrameFillColor

(

const sf::Color &

color

)

Sets the fill color of the legend frame.

Parameters

color

SFML color applied to the frame's background.

setFrameOutlineColor()

void wPlot2D::LegendEntity::setFrameOutlineColor

(

const sf::Color &

color

)

Sets the outline color of the legend frame.

Parameters

color

SFML color applied to the frame's border.

setFrameThickness()

void wPlot2D::LegendEntity::setFrameThickness

(

float

thickness

)

Sets the outline thickness of the legend frame.

Parameters

thickness

Thickness in pixels (positive for outside expansion).

setPadding()

void wPlot2D::LegendEntity::setPadding

(

const sf::Vector2f &

padding

)

Sets the internal padding between items and the frame borders.

Padding defines horizontal and vertical margins in pixels.

Parameters

padding

Vector (x, y) where: x = horizontal padding (left/right), y = vertical padding (top/bottom).

setFont()

void wPlot2D::LegendEntity::setFont

(

const sf::Font &

font

)

Updates the font used for all legend labels.

Note

The font must remain valid during the legend’s lifetime, as SFML does not copy font data internally.

Parameters

font	Reference to an externally managed sf::Font.

setCharacterSize()

void wPlot2D::LegendEntity::setCharacterSize

(

unsigned int

size

)

Sets the character size of the legend text.

Parameters

size	Font size in pixels.

setTextColor()

void wPlot2D::LegendEntity::setTextColor

(

const sf::Color &

color

)

Sets the color of the legend labels.

Parameters

color

SFML color applied to all legend text.

render()

void wPlot2D::LegendEntity::render

(

sf::RenderWindow &

window

)

Renders the legend (all items and optional frame) to the target window.

Each item is drawn with its sample line and label text, aligned inside the legend box. The optional frame is drawn behind all items.

Parameters

window

The target SFML render window.

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

• wLegendEntity.hpp
• wLegendEntity.cpp