RGBA pixel. More...

#include <pixel.hpp>

Public Types
typedef unsigned char	component_type
	The type of the components of the color.

Public Member Functions
	rgba_pixel ()
	Default constructor.
	rgba_pixel (const rgb_pixel &that)
	Constructor.
	rgba_pixel (component_type r, component_type g, component_type b, component_type a)
	Constructor.
	rgba_pixel (const std::string &c)
	Constructor from a color name or code.
rgba_pixel &	operator= (const rgb_pixel &that)
	Assignement operator.
bool	operator== (const rgba_pixel &that) const
	Tell if two pixels are equal.
bool	operator!= (const rgba_pixel &that) const
	Tell if two pixels are different.
component_type	luminosity () const
	Get the luminosity of the pixel.

Public Attributes
union {
unsigned int pixel
	Compressed representation.
struct {
component_type red
	Red component.
component_type green
	Green component.
component_type blue
	Blue component.
component_type alpha
	Translucy.
} components
	Component by component representation.
};

Detailed Description

RGBA pixel.

Definition at line 79 of file pixel.hpp.

Constructor & Destructor Documentation

claw::graphic::rgba_pixel::rgba_pixel ( const rgb_pixel & that )

Constructor.

Parameters

that	The other pixel.

Remarks: The alpha component of this is set to 255.

Definition at line 201 of file pixel.cpp.

References claw::graphic::rgb_pixel::blue, claw::graphic::rgb_pixel::components, claw::graphic::rgb_pixel::green, and claw::graphic::rgb_pixel::red.

claw::graphic::rgba_pixel::rgba_pixel	(	component_type	r,
		component_type	g,
		component_type	b,
		component_type	a
	)

Constructor.

Parameters

r	The value of the red field.
g	The value of the green field.
b	The value of the blue field.
a	The value of the alpha field.

Definition at line 218 of file pixel.cpp.

claw::graphic::rgba_pixel::rgba_pixel ( const std::string & c )

explicit

Constructor from a color name or code.

Parameters

c	The color name or code.

Definition at line 231 of file pixel.cpp.

Member Function Documentation

claw::graphic::rgba_pixel::component_type claw::graphic::rgba_pixel::luminosity ( ) const

Get the luminosity of the pixel.

Returns: The luminosity between 0 (dark) and 255 (light).

The luminosity is approximated with integers: $0,715160 \simeq 183 \div 256 = 0,71484375$ $0,212671 \simeq 54 \div 256 = 0,2109375$ $0,072169 \simeq 18 \div 256 = 0,0703125$