Represents an 8-bit single-channel pixel, and can perform compositing operations on it. More...

Public Types

enum  { indexA = 0 }
 The indexes of the different components in the byte layout of this type of colour. More...
 

Public Member Functions

 PixelAlpha () noexcept
 Creates a pixel without defining its colour. More...
 
 ~PixelAlpha () noexcept
 
forcedinline uint32 getNativeARGB () const noexcept
 Returns a uint32 which represents the pixel in a platform dependent format which is compatible with the native format of a PixelARGB. More...
 
forcedinline uint32 getInARGBMaskOrder () const noexcept
 Returns a uint32 which will be in argb order as if constructed with the following mask operation ((alpha << 24) | (red << 16) | (green << 8) | blue). More...
 
uint32 getInARGBMemoryOrder () const noexcept
 Returns a uint32 which when written to memory, will be in the order a, r, g, b. More...
 
forcedinline uint32 getEvenBytes () const noexcept
 Return channels with an even index and insert zero bytes between them. More...
 
forcedinline uint32 getOddBytes () const noexcept
 Return channels with an odd index and insert zero bytes between them. More...
 
forcedinline uint8 getAlpha () const noexcept
 
forcedinline uint8getAlpha () noexcept
 
forcedinline uint8 getRed () const noexcept
 
forcedinline uint8 getGreen () const noexcept
 
forcedinline uint8 getBlue () const noexcept
 
template<class Pixel >
forcedinline void set (const Pixel &src) noexcept
 Copies another pixel colour over this one. More...
 
forcedinline void setARGB (const uint8 a_, const uint8, const uint8, const uint8) noexcept
 Sets the pixel's colour from individual components. More...
 
template<class Pixel >
forcedinline void blend (const Pixel &src) noexcept
 Blends another pixel onto this one. More...
 
template<class Pixel >
forcedinline void blend (const Pixel &src, uint32 extraAlpha) noexcept
 Blends another pixel onto this one, applying an extra multiplier to its opacity. More...
 
template<class Pixel >
forcedinline void tween (const Pixel &src, const uint32 amount) noexcept
 Blends another pixel with this one, creating a colour that is somewhere between the two, as specified by the amount. More...
 
forcedinline void setAlpha (const uint8 newAlpha) noexcept
 Replaces the colour's alpha value with another one. More...
 
forcedinline void multiplyAlpha (int multiplier) noexcept
 Multiplies the colour's alpha value with another one. More...
 
forcedinline void multiplyAlpha (const float multiplier) noexcept
 
forcedinline void premultiply () noexcept
 Premultiplies the pixel's RGB values by its alpha. More...
 
forcedinline void unpremultiply () noexcept
 Unpremultiplies the pixel's RGB values. More...
 
forcedinline void desaturate () noexcept
 

Detailed Description

Represents an 8-bit single-channel pixel, and can perform compositing operations on it.

This is used internally by the imaging classes.

See also
PixelARGB, PixelRGB

Member Enumeration Documentation

anonymous enum

The indexes of the different components in the byte layout of this type of colour.

Enumerator
indexA 

Constructor & Destructor Documentation

PixelAlpha::PixelAlpha ( )
noexcept

Creates a pixel without defining its colour.

PixelAlpha::~PixelAlpha ( )
noexcept

Member Function Documentation

forcedinline uint32 PixelAlpha::getNativeARGB ( ) const
noexcept

Returns a uint32 which represents the pixel in a platform dependent format which is compatible with the native format of a PixelARGB.

See also
PixelARGB::getNativeARGB
forcedinline uint32 PixelAlpha::getInARGBMaskOrder ( ) const
noexcept

Returns a uint32 which will be in argb order as if constructed with the following mask operation ((alpha << 24) | (red << 16) | (green << 8) | blue).

uint32 PixelAlpha::getInARGBMemoryOrder ( ) const
noexcept

Returns a uint32 which when written to memory, will be in the order a, r, g, b.

In other words, if the return-value is read as a uint8 array then the elements will be in the order of a, r, g, b

forcedinline uint32 PixelAlpha::getEvenBytes ( ) const
noexcept

Return channels with an even index and insert zero bytes between them.

This is useful for blending operations. The exact channels which are returned is platform dependent but compatible with the return value of getEvenBytes of the PixelARGB class.

See also
PixelARGB::getEvenBytes
forcedinline uint32 PixelAlpha::getOddBytes ( ) const
noexcept

Return channels with an odd index and insert zero bytes between them.

This is useful for blending operations. The exact channels which are returned is platform dependent but compatible with the return value of getOddBytes of the PixelARGB class.

See also
PixelARGB::getOddBytes
forcedinline uint8 PixelAlpha::getAlpha ( ) const
noexcept
forcedinline uint8& PixelAlpha::getAlpha ( )
noexcept
forcedinline uint8 PixelAlpha::getRed ( ) const
noexcept
forcedinline uint8 PixelAlpha::getGreen ( ) const
noexcept
forcedinline uint8 PixelAlpha::getBlue ( ) const
noexcept
template<class Pixel >
forcedinline void PixelAlpha::set ( const Pixel &  src)
noexcept

Copies another pixel colour over this one.

This doesn't blend it - this colour is simply replaced by the other one.

forcedinline void PixelAlpha::setARGB ( const uint8  a_,
const uint8  ,
const uint8  ,
const uint8   
)
noexcept

Sets the pixel's colour from individual components.

template<class Pixel >
forcedinline void PixelAlpha::blend ( const Pixel &  src)
noexcept

Blends another pixel onto this one.

This takes into account the opacity of the pixel being overlaid, and blends it accordingly.

template<class Pixel >
forcedinline void PixelAlpha::blend ( const Pixel &  src,
uint32  extraAlpha 
)
noexcept

Blends another pixel onto this one, applying an extra multiplier to its opacity.

The opacity of the pixel being overlaid is scaled by the extraAlpha factor before being used, so this can blend semi-transparently from a PixelRGB argument.

template<class Pixel >
forcedinline void PixelAlpha::tween ( const Pixel &  src,
const uint32  amount 
)
noexcept

Blends another pixel with this one, creating a colour that is somewhere between the two, as specified by the amount.

forcedinline void PixelAlpha::setAlpha ( const uint8  newAlpha)
noexcept

Replaces the colour's alpha value with another one.

forcedinline void PixelAlpha::multiplyAlpha ( int  multiplier)
noexcept

Multiplies the colour's alpha value with another one.

forcedinline void PixelAlpha::multiplyAlpha ( const float  multiplier)
noexcept
forcedinline void PixelAlpha::premultiply ( )
noexcept

Premultiplies the pixel's RGB values by its alpha.

forcedinline void PixelAlpha::unpremultiply ( )
noexcept

Unpremultiplies the pixel's RGB values.

forcedinline void PixelAlpha::desaturate ( )
noexcept

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