ColorMap Class Reference

A ColorMap contains a series of sequential color steps that can be used for generating colors by interpolation. More...

Public Types
enum class	Interpolation { rgba , hsv , hsl }
	Interpolation color space method. More...
using	StepsArray = std::vector< Color >
	Type used for color steps array. More...

Public Member Functions
	ColorMap (Interpolation interp) noexcept
template<class T >
	ColorMap (std::initializer_list< T > steps, Interpolation interp=Interpolation::rgba)
	ColorMap (StepsArray steps, Interpolation interp=Interpolation::rgba)
size_t	count () const
	Count the number of color steps. More...
bool	empty () const
	Are there any color steps? More...
Color	interp (float t) const
	Get a color at the specified offset. More...
Color	interp_cached (float t, size_t accuracy=1000) const
	Get a color at the specified offset. More...
void	step (const Color &color)
	Append a color step. More...
const StepsArray &	steps () const
	Get a reference to the color steps array. More...
void	steps (const StepsArray &steps)
	Set the color steps. More...

Protected Attributes
std::array< std::map< size_t, Color >, 3 >	m_cache {}
	Interpolation cache. More...
Interpolation	m_interp {Interpolation::rgba}
	Interpolation color space method. More...
StepsArray	m_steps
	Steps in the color map. More...

Detailed Description

A ColorMap contains a series of sequential color steps that can be used for generating colors by interpolation.

Member Typedef Documentation

StepsArray

using StepsArray = std::vector<Color>

Type used for color steps array.

Member Enumeration Documentation

Interpolation

enum Interpolation

strong

Interpolation color space method.

Enumerator
rgba
hsv
hsl

Constructor & Destructor Documentation

ColorMap() [1/3]

ColorMap ( Interpolation  interp )

inlineexplicitnoexcept

Parameters

[in]

interp

Interpolation color space.

ColorMap() [2/3]

ColorMap ( StepsArray  steps, Interpolation  interp = Interpolation::rgba  )

inlineexplicit

Parameters

[in]	steps	Pre-defined color steps.
[in]	interp	Interpolation color space.

ColorMap() [3/3]

ColorMap ( std::initializer_list< T >  steps, Interpolation  interp = Interpolation::rgba  )

inlineexplicit

Parameters

[in]	steps	Pre-defined color steps.
[in]	interp	Interpolation color space.

Member Function Documentation

count()

size_t count ( ) const

inline

Count the number of color steps.

empty()

bool empty ( ) const

inline

Are there any color steps?

interp()

Color interp

(

float

t

)

const

Get a color at the specified offset.

Parameters

[in]

t

Offset from 0 to 1.

interp_cached()

Color interp_cached	(	float	t,
		size_t	accuracy = 1000
	)		const

Get a color at the specified offset.

This will use a cache to speed up repetitive calls to interpolate.

Parameters

[in]	t	Offset from 0 to 1.
[in]	accuracy	Accuracy of the cached result.

step()

void step ( const Color &  color )

inline

Append a color step.

steps() [1/2]

const StepsArray& steps ( ) const

inline

Get a reference to the color steps array.

steps() [2/2]

void steps ( const StepsArray &  steps )

inline

Set the color steps.

Member Data Documentation

m_cache

std::array<std::map<size_t, Color>, 3> m_cache {}

mutableprotected

Interpolation cache.

m_interp

Interpolation m_interp {Interpolation::rgba}

protected

Interpolation color space method.

m_steps

StepsArray m_steps

protected

Steps in the color map.