Represents a mathematical function as a drawable entity in a 2D plot. More...

#include <wFunctionEntity.hpp>

Inheritance diagram for wPlot2D::FunctionEntity:

Public Member Functions
	FunctionEntity (const sf::Vector2f origin, const sf::Vector2f scale, std::function< double(double) > func)
	Construct a new FunctionEntity.
virtual	~FunctionEntity ()=default
	Virtual destructor.
sf::Vector2f	getPosition () const
	Get the position (origin) of the function in pixel space.
sf::Color	getColor () const
	Get the color of the function curve.
float	getThickness () const
	Get the line thickness of the function curve.
wEngine::LineStyleComponent::LineStyle	getLineStyle () const
	Get the line style of the function curve.
float	getDashLength () const
	Get the dash length when the line style is Dashed.
float	getGapLength () const
	Get the gap length between dashes or dots.
sf::Vector2f	getOffset () const
	Get the current offset applied to the function curve.
float	getRotation () const
	Get the current rotation angle of the function curve.
void	setPosition (sf::Vector2f position)
	Set the position (origin) of the function in pixel space.
void	setColor (sf::Color color)
	Set the color of the function curve.
void	setThickness (float thickness)
	Set the line thickness of the function curve.
void	setLineStyle (wEngine::LineStyleComponent::LineStyle style)
	Set the line style of the function curve.
void	setDashLength (float dashLength)
	Set the length of each dash when the line style is Dashed.
void	setGapLength (float gapLength)
	Set the length of the gap between dashes or dots.
void	setOffset (float offsetX, float offsetY)
	Set an offset applied to the function curve.
void	setRotation (float angleDegrees)
	Set the rotation angle of the function curve.
void	setScale (sf::Vector2f scale)
	Sets the scaling factors for the function graph.
void	addExcludedInterval (double min, double max)
	Add an excluded interval where the function should not be drawn.
void	clearExcludedIntervals ()
	Clear all excluded intervals.
void	alignToYAxis (float normalizedOffsetX=0.0f, float normalizedOffsetY=0.0f)
	Rotates the function by 90 degrees and swaps scales accordingly.
void	drawFunction (sf::RenderWindow &window, double startX, double endX, size_t nbPoints=1000)
	Draw the function on 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 mathematical function as a drawable entity in a 2D plot.

A FunctionEntity manages all components required to render a curve:

Origin and scale (mapping logical space to pixels).
Color, thickness, and line style (solid, dashed, dotted).
Offset and rotation of the curve.
Discontinuities handled by excluded intervals.

The function is sampled at evenly spaced x-values and rendered as a polyline. Excluded intervals and invalid values (NaN, Inf) split the curve into separate segments.

Author: Wilfried Koch

Copyright: © 2025 Wilfried Koch. All rights reserved.

Constructor & Destructor Documentation

◆ FunctionEntity()

wPlot2D::FunctionEntity::FunctionEntity	(	const sf::Vector2f	origin,
		const sf::Vector2f	scale,
		std::function< double(double) >	func )

Construct a new FunctionEntity.

Parameters

origin	Logical origin of the coordinate system (pixels).
scale	Scale factors for x and y (pixels per unit).
func	Function of type double(double) to be plotted.

◆ ~FunctionEntity()

virtual wPlot2D::FunctionEntity::~FunctionEntity ( )

virtualdefault

Virtual destructor.

Member Function Documentation

◆ getPosition()

sf::Vector2f wPlot2D::FunctionEntity::getPosition ( ) const

nodiscard

Get the position (origin) of the function in pixel space.

Returns: The current origin as an sf::Vector2f.

◆ getColor()

sf::Color wPlot2D::FunctionEntity::getColor ( ) const

nodiscard

Get the color of the function curve.

Returns: The current curve color.

◆ getThickness()

float wPlot2D::FunctionEntity::getThickness ( ) const

nodiscard

Get the line thickness of the function curve.

Returns: The thickness in pixels.

◆ getLineStyle()

wEngine::LineStyleComponent::LineStyle wPlot2D::FunctionEntity::getLineStyle ( ) const

nodiscard

Get the line style of the function curve.

Returns: The current line style (Solid, Dashed, or Dotted).

◆ getDashLength()

float wPlot2D::FunctionEntity::getDashLength ( ) const

nodiscard

Get the dash length when the line style is Dashed.

Returns: Dash length in pixels.

Note: This value has no effect if the style is not Dashed.

◆ getGapLength()

float wPlot2D::FunctionEntity::getGapLength ( ) const

nodiscard

Get the gap length between dashes or dots.

Returns: Gap length in pixels.

Note: This setting affects both Dashed and Dotted line styles.

◆ getOffset()

sf::Vector2f wPlot2D::FunctionEntity::getOffset ( ) const

nodiscard

Get the current offset applied to the function curve.

Returns: A 2D vector containing the (x,y) offset in pixels.

◆ getRotation()

float wPlot2D::FunctionEntity::getRotation ( ) const

nodiscard

Get the current rotation angle of the function curve.

Returns: The rotation angle in degrees.

◆ setPosition()

void wPlot2D::FunctionEntity::setPosition ( sf::Vector2f position )

Set the position (origin) of the function in pixel space.

Parameters

position The new origin as an sf::Vector2f.

◆ setColor()

void wPlot2D::FunctionEntity::setColor ( sf::Color color )

Set the color of the function curve.

Parameters

color The new color as an sf::Color.

◆ setThickness()

void wPlot2D::FunctionEntity::setThickness ( float thickness )

Set the line thickness of the function curve.

Parameters

thickness The new line thickness in pixels.

◆ setLineStyle()

void wPlot2D::FunctionEntity::setLineStyle ( wEngine::LineStyleComponent::LineStyle style )

Set the line style of the function curve.

Parameters

style The new style (Solid, Dashed, or Dotted).

◆ setDashLength()

void wPlot2D::FunctionEntity::setDashLength ( float dashLength )

Set the length of each dash when the line style is Dashed.

Parameters

dashLength The dash length in pixels (must be > 0).

Exceptions

std::invalid_argument if dashLength <= 0.

Note: This setting has no effect if the line style is not Dashed.

◆ setGapLength()

void wPlot2D::FunctionEntity::setGapLength ( float gapLength )

Set the length of the gap between dashes or dots.

Parameters

gapLength The gap length in pixels (must be >= 0).

Exceptions

std::invalid_argument if gapLength < 0.

Note: This setting affects both Dashed and Dotted line styles.

◆ setOffset()

void wPlot2D::FunctionEntity::setOffset	(	float	offsetX,
		float	offsetY )

Set an offset applied to the function curve.

The offset is applied after scaling and rotation, allowing the curve to be shifted horizontally and vertically relative to its logical origin.

Parameters

offsetX	Horizontal offset in pixels.
offsetY	Vertical offset in pixels.

◆ setRotation()

void wPlot2D::FunctionEntity::setRotation ( float angleDegrees )

Set the rotation angle of the function curve.

The rotation is applied around the logical origin of the graph. The angle is expressed in degrees, with positive values corresponding to counter-clockwise rotation.

Parameters

angleDegrees Rotation angle in degrees.

◆ setScale()

void wPlot2D::FunctionEntity::setScale ( sf::Vector2f scale )

Sets the scaling factors for the function graph.

This method updates the ScaleComponent so the user can control how much the x and y coordinates are stretched on screen.

Parameters

scale The new scaling vector (scale.x, scale.y).

◆ addExcludedInterval()

void wPlot2D::FunctionEntity::addExcludedInterval	(	double	min,
		double	max )

Add an excluded interval where the function should not be drawn.

Useful to handle discontinuities such as vertical asymptotes.

Parameters

min	Left bound of the interval.
max	Right bound of the interval.

◆ clearExcludedIntervals()

void wPlot2D::FunctionEntity::clearExcludedIntervals ( )

Clear all excluded intervals.

◆ alignToYAxis()

void wPlot2D::FunctionEntity::alignToYAxis	(	float	normalizedOffsetX = 0.0f,
		float	normalizedOffsetY = 0.0f )

Rotates the function by 90 degrees and swaps scales accordingly.

This is a common operation when we want to interpret the function's values along the X-axis instead of the Y-axis (or vice versa). The method:

Sets a 90 degrees rotation.
Swaps scale.x and scale.y to preserve unit consistency.
Applies an optional normalized offset for alignment.

Parameters

normalizedOffsetX	Relative offset along X after rotation, expressed in units of (oldScaleX / oldScaleY).
normalizedOffsetY	Relative offset along Y after rotation, expressed in units of (oldScaleY / oldScaleX).

◆ drawFunction()

void wPlot2D::FunctionEntity::drawFunction	(	sf::RenderWindow &	window,
		double	startX,
		double	endX,
		size_t	nbPoints = 1000 )

Draw the function on the target window.

Parameters

window	Render target.
startX	Start of the logical x-range.
endX	End of the logical x-range.
nbPoints	Number of points to sample (default: 1000).

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

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ FunctionEntity()

◆ ~FunctionEntity()

Member Function Documentation

◆ getPosition()

◆ getColor()

◆ getThickness()

◆ getLineStyle()

◆ getDashLength()

◆ getGapLength()

◆ getOffset()

◆ getRotation()

◆ setPosition()

◆ setColor()

◆ setThickness()

◆ setLineStyle()

◆ setDashLength()

◆ setGapLength()

◆ setOffset()

◆ setRotation()

◆ setScale()

◆ addExcludedInterval()

◆ clearExcludedIntervals()

◆ alignToYAxis()

◆ drawFunction()