Color

The color sys module supports handling RGB and HSV color. More...

Detailed Description

The color sys module supports handling RGB and HSV color.

Files
file	color.h
	Headers for the color handling module.

Data Structures
struct	color_rgb_t
	Data-structure describing a RGB color. More...
struct	color_rgba_t
	RGBA color value. More...
struct	color_hsv_t
	Data-structure for holding HSV colors. More...

Functions
void	color_rgb2hsv (color_rgb_t *rgb, color_hsv_t *hsv)
	Convert RGB color to HSV color.
void	color_hsv2rgb (color_hsv_t *hsv, color_rgb_t *rgb)
	Convert HSV color to RGB color.
void	color_hex2rgb (const uint32_t hex, color_rgb_t *rgb)
	Convert a hex value of the form 0x00RRGGBB to an RGB color struct.
void	color_rgb2hex (const color_rgb_t *rgb, uint32_t *hex)
	Convert a rgb struct to a hex value of the form 0x00RRGGBB.
void	color_str2rgb (const char *str, color_rgb_t *color)
	Convert a hex color string of the form 'RRGGBB' to a color_rgb_t struct.
void	color_rgb2str (const color_rgb_t *rgb, char *str)
	Convert a color_rgb_t struct to a hex color string of the form 'RRGGBB'.
static void	color_rgb_invert (const color_rgb_t *rgb, color_rgb_t *inv_rgb)
	Invert a given rgb color.
static void	color_rgb_shift (const color_rgb_t *rgb, color_rgb_t *out, int8_t shift)
	Shifts a given rgb color to change it's brightness.
static void	color_rgb_set_brightness (const color_rgb_t *rgb, color_rgb_t *out, uint8_t level)
	Change the brightness of a RGB color by multiplying it with a set factor.
void	color_rgb_complementary (const color_rgb_t *rgb, color_rgb_t *comp_rgb)
	Calculate the complementary color of a given rgb color.

Function Documentation

color_hex2rgb()

void color_hex2rgb	(	const uint32_t	hex,
		color_rgb_t *	rgb
	)

Convert a hex value of the form 0x00RRGGBB to an RGB color struct.

Note

the two most significant bytes of hex will be ignored

Parameters

[in]	hex	Input color encoded in hex
[out]	rgb	Output color encoded in RGB space

color_hsv2rgb()

void color_hsv2rgb	(	color_hsv_t *	hsv,
		color_rgb_t *	rgb
	)

Convert HSV color to RGB color.

Parameters

[in]	hsv	Input color encoded in HSV space
[out]	rgb	Output color encoded in RGB space

color_rgb2hex()

void color_rgb2hex	(	const color_rgb_t *	rgb,
		uint32_t *	hex
	)

Convert a rgb struct to a hex value of the form 0x00RRGGBB.

Note

the two most significant bytes of hex will be 0

Parameters

[in]	rgb	Input color encoded in RGB space
[out]	hex	Output color encoded in hex

color_rgb2hsv()

void color_rgb2hsv	(	color_rgb_t *	rgb,
		color_hsv_t *	hsv
	)

Convert RGB color to HSV color.

Parameters

[in]	rgb	Input color encoded in RGB space
[out]	hsv	Output color encoded in HSV space

color_rgb2str()

void color_rgb2str	(	const color_rgb_t *	rgb,
		char *	str
	)

Convert a color_rgb_t struct to a hex color string of the form 'RRGGBB'.

Note

str MUST be big enough to hold 6 characters

Parameters

[in]	rgb	Input color encoded in RGB space
[out]	str	Output color encoded as string of the form 'RRGGBB'

color_rgb_complementary()

void color_rgb_complementary	(	const color_rgb_t *	rgb,
		color_rgb_t *	comp_rgb
	)

Calculate the complementary color of a given rgb color.

Note

Complementary color calculation according to adobe illustator calculations. See https://helpx.adobe.com/illustrator/using/adjusting-colors.html

Precondition

((rgb != NULL) && (comp_rgb != NULL))

Parameters

[in]	rgb	Input rgb color. Must be NOT NULL
[out]	comp_rgb	Output rgb color, result of the complementary color calculation. Must be NOT NULL

color_rgb_invert()

static void color_rgb_invert ( const color_rgb_t *  rgb, color_rgb_t *  inv_rgb  )

inlinestatic

Invert a given rgb color.

Precondition

((rgb != NULL) && (inv_rgb != NULL))

Parameters

[in]	rgb	Input rgb color, that should be converted. Must be NOT NULL
[out]	inv_rgb	Output rgb color, result of the conversion. Must be NOT NULL

Definition at line 123 of file color.h.

color_rgb_set_brightness()

static void color_rgb_set_brightness ( const color_rgb_t *  rgb, color_rgb_t *  out, uint8_t  level  )

inlinestatic

Change the brightness of a RGB color by multiplying it with a set factor.

Precondition

((rgb != NULL) && (out != NULL))

Parameters

[in]	rgb	Input rgb color, that should be multiplied. Must be NOT NULL
[out]	out	Output rgb color. Must be NOT NULL
[in]	level	New brightness level. 255 = Full Brightness, 0 = Off.

Definition at line 162 of file color.h.

color_rgb_shift()

static void color_rgb_shift ( const color_rgb_t *  rgb, color_rgb_t *  out, int8_t  shift  )

inlinestatic

Shifts a given rgb color to change it's brightness.

Precondition

((rgb != NULL) && (out != NULL))

Parameters

[in]	rgb	Input rgb color, that should be shifted. Must be NOT NULL
[out]	out	Output rgb color, result of the shift. Must be NOT NULL
[in]	shift	Amount by which the color components should be shifted. May be positive (shift to left) or negative (shift to right).

Definition at line 140 of file color.h.

color_str2rgb()

void color_str2rgb	(	const char *	str,
		color_rgb_t *	color
	)

Convert a hex color string of the form 'RRGGBB' to a color_rgb_t struct.

Note

str MUST contain only hexadecimal digits. Expect unexpected behaviour, otherwise.

Parameters

[in]	str	Input color encoded as string of the form 'RRGGBB'
[out]	color	Output color encoded in RGB space