LineGenerator Class Reference

A class for generating and storing a line shape, defined by a series of points and associated powers. More...

#include <line_generator.h>

Public Member Functions
	LineGenerator (int resolution=kDefaultResolution)
	Constructs a LineGenerator with a given resolution.
virtual	~LineGenerator ()
	Virtual destructor.
void	setLoop (bool loop)
	Sets whether the line should loop at the end.
void	setName (const std::string &name)
	Sets a name identifier for the line.
void	setLastBrowsedFile (const std::string &path)
	Stores the last browsed file path associated with this line.
void	setSmooth (bool smooth)
	Enables or disables smoothing behavior.
void	initLinear ()
	Initializes the line to a simple linear shape (from 1.0 at x=0 to 0.0 at x=1).
void	initTriangle ()
	Initializes the line as a triangle shape.
void	initSquare ()
	Initializes the line as a square shape.
void	initSin ()
	Initializes the line as a sine-like shape.
void	initSawUp ()
	Initializes the line as a "saw up" shape.
void	initSawDown ()
	Initializes the line as a "saw down" shape.
void	render ()
	Renders the line into the internal buffer based on the current points and settings.
json	stateToJson ()
	Converts the current state of the line into a JSON object.
void	jsonToState (json data)
	Restores the line state from a given JSON object.
float	valueAtPhase (float phase)
	Gets the line value at a given normalized phase.
void	checkLineIsLinear ()
	Checks if the line is the default linear shape.
float	getValueBetweenPoints (float x, int index_from, int index_to)
	Interpolates a value between two points at a given x position.
float	getValueAtPhase (float phase)
	Returns the value of the line at a given phase by searching through the points.
std::string	getName () const
	Gets the current name of the line.
std::string	getLastBrowsedFile () const
	Gets the last browsed file path associated with this line.
void	addPoint (int index, std::pair< float, float > position)
	Inserts a new point into the line at a specified index.
void	addMiddlePoint (int index)
	Inserts a point exactly between two existing points.
void	removePoint (int index)
	Removes the point at a specified index.
void	flipHorizontal ()
	Flips the line horizontally around the x=0.5 vertical axis.
void	flipVertical ()
	Flips the line vertically around y=0.5.
std::pair< float, float >	lastPoint () const
	Returns the last point in the line.
float	lastPower () const
	Returns the power (interpolation shape factor) of the last point.
force_inline int	resolution () const
	Gets the resolution of the line's internal buffer.
force_inline bool	linear () const
	Indicates whether the line is currently a simple linear shape.
force_inline bool	smooth () const
	Indicates whether smoothing is enabled.
force_inline vital::mono_float *	getBuffer () const
	Gets a pointer to the internal buffer used for interpolation.
force_inline vital::mono_float *	getCubicInterpolationBuffer () const
	Gets a pointer to the buffer used for cubic interpolation.
force_inline std::pair< float, float >	getPoint (int index) const
	Returns a point at the given index.
force_inline float	getPower (int index) const
	Returns the power at the given index.
force_inline int	getNumPoints () const
	Returns the current number of points defining the line.
force_inline void	setPoint (int index, std::pair< float, float > point)
	Sets the position of a specific point.
force_inline void	setPower (int index, float power)
	Sets the power for a specific point.
force_inline void	setNumPoints (int num_points)
	Sets the number of points currently in use.
int	getRenderCount () const
	Gets the number of times the line has been rendered since initialization.

Static Public Member Functions
static force_inline float	smoothTransition (float t)
	Smooth transition function for smoothing between points.
static bool	isValidJson (json data)
	Checks if a given JSON object contains valid line data.

Static Public Attributes
static constexpr int	kMaxPoints = 100
	Maximum number of points that can define the line.
static constexpr int	kDefaultResolution = 2048
	Default resolution of the rendered line buffer.
static constexpr int	kExtraValues = 3
	Extra buffer values used for interpolation outside the main range.

Protected Attributes
std::string	name_
	The name of the line shape.
std::string	last_browsed_file_
	The last browsed file path for saving/loading this line.
std::pair< float, float >	points_ [kMaxPoints]
	Array of points defining the line shape.
float	powers_ [kMaxPoints]
	Powers controlling interpolation shape between points.
int	num_points_
	Current number of points.
int	resolution_
	Resolution of the internal buffer.
std::unique_ptr< vital::mono_float[]>	buffer_
	Internal buffer holding the rendered line values.
bool	loop_
	Whether the line loops at the end.
bool	smooth_
	Whether to apply smoothing between points.
bool	linear_
	Whether the line is the simple linear shape.
int	render_count_
	Count of how many times render() was called.

Detailed Description

A class for generating and storing a line shape, defined by a series of points and associated powers.

The LineGenerator manages a set of control points and their associated interpolation powers to generate a line shape. This line can represent a waveform, an envelope, or any parameter that changes smoothly (or linearly) over a normalized 0.0 to 1.0 range.

The class supports various presets (linear, triangle, square, sine, sawtooth), optional looping behavior, and configurable smoothing. It also provides JSON serialization and deserialization to save and load states, as well as utility methods to flip the line horizontally or vertically.

Constructor & Destructor Documentation

LineGenerator()

LineGenerator::LineGenerator

(

int

resolution = kDefaultResolution

)

Constructs a LineGenerator with a given resolution.

Parameters

resolution

The number of samples in the generated buffer. Defaults to kDefaultResolution.

~LineGenerator()

virtual LineGenerator::~LineGenerator ( )

inlinevirtual

Virtual destructor.

Member Function Documentation

addMiddlePoint()

void LineGenerator::addMiddlePoint

(

int

index

)

Inserts a point exactly between two existing points.

This finds the midpoint between points[index-1] and points[index], and adds a new point there.

Parameters

index

The index after which the middle point will be inserted.

addPoint()

void LineGenerator::addPoint	(	int	index,
		std::pair< float, float >	position )

Inserts a new point into the line at a specified index.

The number of points increases by one. Existing points from index onward are shifted.

Parameters

index	The position to insert the new point.
position	The (x, y) coordinates of the new point.

checkLineIsLinear()

void LineGenerator::checkLineIsLinear

(

)

Checks if the line is the default linear shape.

This updates the linear_ member based on the current points and smoothness setting.

flipHorizontal()

void LineGenerator::flipHorizontal

(

)

Flips the line horizontally around the x=0.5 vertical axis.

This reverses the order of points and their x-values to mirror the shape horizontally.

flipVertical()

void LineGenerator::flipVertical

(

)

Flips the line vertically around y=0.5.

This inverts the y-values of the points, mirroring the shape vertically.

getBuffer()

force_inline vital::mono_float * LineGenerator::getBuffer ( ) const

inline

Gets a pointer to the internal buffer used for interpolation.

This returns the buffer starting from index 1, which is typically how the lookup is performed.

Returns

A pointer to the buffer.

getCubicInterpolationBuffer()

force_inline vital::mono_float * LineGenerator::getCubicInterpolationBuffer ( ) const

inline

Gets a pointer to the buffer used for cubic interpolation.

This returns the buffer from index 0, allowing for additional interpolation techniques.

Returns

A pointer to the buffer.

getLastBrowsedFile()

std::string LineGenerator::getLastBrowsedFile ( ) const

inline

Gets the last browsed file path associated with this line.

Returns

The file path as a string.

getName()

std::string LineGenerator::getName ( ) const

inline

Gets the current name of the line.

Returns

The line name.

getNumPoints()

force_inline int LineGenerator::getNumPoints ( ) const

inline

Returns the current number of points defining the line.

Returns

The number of points.

getPoint()

force_inline std::pair< float, float > LineGenerator::getPoint ( int index ) const

inline

Returns a point at the given index.

Parameters

index

The point index (0-based).

Returns

A pair (x, y) representing the point's coordinates.

getPower()

force_inline float LineGenerator::getPower ( int index ) const

inline

Returns the power at the given index.

Parameters

index

The point index.

Returns

The power value for that point.

getRenderCount()

int LineGenerator::getRenderCount ( ) const

inline

Gets the number of times the line has been rendered since initialization.

Returns

The render count.

getValueAtPhase()

float LineGenerator::getValueAtPhase

(

float

phase

)

Returns the value of the line at a given phase by searching through the points.

Parameters

phase

A value between 0.0 and 1.0.

Returns

The interpolated line value at the given phase.

getValueBetweenPoints()

float LineGenerator::getValueBetweenPoints	(	float	x,
		int	index_from,
		int	index_to )

Interpolates a value between two points at a given x position.

Parameters

x	The x-coordinate between the two points.
index_from	The index of the starting point.
index_to	The index of the ending point.

Returns

The interpolated y-value at x.

initLinear()

void LineGenerator::initLinear

(

)

Initializes the line to a simple linear shape (from 1.0 at x=0 to 0.0 at x=1).

initSawDown()

void LineGenerator::initSawDown

(

)

Initializes the line as a "saw down" shape.

initSawUp()

void LineGenerator::initSawUp

(

)

Initializes the line as a "saw up" shape.

initSin()

void LineGenerator::initSin

(

)

Initializes the line as a sine-like shape.

initSquare()

void LineGenerator::initSquare

(

)

Initializes the line as a square shape.

initTriangle()

void LineGenerator::initTriangle

(

)

Initializes the line as a triangle shape.

isValidJson()

bool LineGenerator::isValidJson ( json data )

static

Checks if a given JSON object contains valid line data.

Parameters

data	The JSON object to check.

Returns

True if valid, false otherwise.

jsonToState()

void LineGenerator::jsonToState

(

json

data

)

Restores the line state from a given JSON object.

Parameters

data	A JSON object previously generated by stateToJson().

lastPoint()

std::pair< float, float > LineGenerator::lastPoint ( ) const

inline

Returns the last point in the line.

Returns

A pair representing the (x, y) coordinates of the last point.

lastPower()

float LineGenerator::lastPower ( ) const

inline

Returns the power (interpolation shape factor) of the last point.

Returns

A float representing the power of the last point.

linear()

force_inline bool LineGenerator::linear ( ) const

inline

Indicates whether the line is currently a simple linear shape.

Returns

True if linear, false otherwise.

removePoint()

void LineGenerator::removePoint

(

int

index

)

Removes the point at a specified index.

Parameters

index

The position of the point to remove.

render()

void LineGenerator::render

(

)

Renders the line into the internal buffer based on the current points and settings.

This method should be called after modifying points, powers, or other parameters. It updates the internal buffer used for fast lookups.

resolution()

force_inline int LineGenerator::resolution ( ) const

inline

Gets the resolution of the line's internal buffer.

Returns

The resolution, typically kDefaultResolution.

setLastBrowsedFile()

void LineGenerator::setLastBrowsedFile ( const std::string & path )

inline

Stores the last browsed file path associated with this line.

Parameters

path	The file path.

setLoop()

void LineGenerator::setLoop ( bool loop )

inline

Sets whether the line should loop at the end.

If loop is true, the line wraps around from the end back to the start for continuous interpolation.

Parameters

loop	True to enable looping, false otherwise.

setName()

void LineGenerator::setName ( const std::string & name )

inline

Sets a name identifier for the line.

Parameters

name	A string representing the line's name.

setNumPoints()

force_inline void LineGenerator::setNumPoints ( int num_points )

inline

Sets the number of points currently in use.

Parameters

num_points

The new number of points.

setPoint()

force_inline void LineGenerator::setPoint ( int index, std::pair< float, float > point )

inline

Sets the position of a specific point.

Parameters

index	The point index to modify.
point	The new (x, y) coordinates for that point.

setPower()

force_inline void LineGenerator::setPower ( int index, float power )

inline

Sets the power for a specific point.

Parameters

index	The point index to modify.
power	The new power value.

setSmooth()

void LineGenerator::setSmooth ( bool smooth )

inline

Enables or disables smoothing behavior.

Smoothing affects how values between points are interpolated. When smoothing is enabled, the transitions between points are softened.

Parameters

smooth

True to enable smoothing, false to disable.

smooth()

force_inline bool LineGenerator::smooth ( ) const

inline

Indicates whether smoothing is enabled.

Returns

True if smoothing is enabled, false otherwise.

smoothTransition()

static force_inline float LineGenerator::smoothTransition ( float t )

inlinestatic

Smooth transition function for smoothing between points.

This function applies a sine-based smoothing to a normalized parameter t, producing a smooth transition curve.

Parameters

t	A normalized value between 0.0 and 1.0.

Returns

The smoothed value.

stateToJson()

json LineGenerator::stateToJson

(

)

Converts the current state of the line into a JSON object.

The JSON includes the number of points, their positions, powers, name, and smooth setting.

Returns

A JSON object representing the current line state.

valueAtPhase()

float LineGenerator::valueAtPhase

(

float

phase

)

Gets the line value at a given normalized phase.

Parameters

phase

A value between 0.0 and 1.0 representing a position along the line.

Returns

The interpolated line value at the given phase.

Member Data Documentation

buffer_

std::unique_ptr<vital::mono_float[]> LineGenerator::buffer_

protected

Internal buffer holding the rendered line values.

kDefaultResolution

int LineGenerator::kDefaultResolution = 2048

staticconstexpr

Default resolution of the rendered line buffer.

This is the number of samples (points) in the generated line buffer. Higher resolution results in finer granularity.

kExtraValues

int LineGenerator::kExtraValues = 3

staticconstexpr

Extra buffer values used for interpolation outside the main range.

A small number of extra samples are stored to facilitate safe interpolation at buffer edges.

kMaxPoints

int LineGenerator::kMaxPoints = 100

staticconstexpr

Maximum number of points that can define the line.

last_browsed_file_

std::string LineGenerator::last_browsed_file_

protected

The last browsed file path for saving/loading this line.

linear_

bool LineGenerator::linear_

protected

Whether the line is the simple linear shape.

loop_

bool LineGenerator::loop_

protected

Whether the line loops at the end.

name_

std::string LineGenerator::name_

protected

The name of the line shape.

num_points_

int LineGenerator::num_points_

protected

Current number of points.

points_

std::pair<float, float> LineGenerator::points_[kMaxPoints]

protected

Array of points defining the line shape.

powers_

float LineGenerator::powers_[kMaxPoints]

protected

Powers controlling interpolation shape between points.

render_count_

int LineGenerator::render_count_

protected

Count of how many times render() was called.

resolution_

int LineGenerator::resolution_

protected

Resolution of the internal buffer.

smooth_

bool LineGenerator::smooth_

protected

Whether to apply smoothing between points.

---

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

• /Users/davidvogel/repos/VitalHelp/src/common/line_generator.h
• /Users/davidvogel/repos/VitalHelp/src/common/line_generator.cpp