# Color addon

These functions are declared in the following header file. Link with allegro_color.

     #include <allegro5/allegro_color.h>

# al_color_cmyk

    ALLEGRO_COLOR al_color_cmyk(float c, float m, float y, float k)

Return an ALLEGRO_COLOR structure from CMYK values (cyan, magenta, yellow, black).

See also: al_color_cmyk_to_rgb, al_color_rgb_to_cmyk

# al_color_cmyk_to_rgb

    void al_color_cmyk_to_rgb(float cyan, float magenta, float yellow,
        float key, float *red, float *green, float *blue)

Convert CMYK values to RGB values.

See also: al_color_cmyk, al_color_rgb_to_cmyk

# al_color_hsl

    ALLEGRO_COLOR al_color_hsl(float h, float s, float l)

Return an ALLEGRO_COLOR structure from HSL (hue, saturation, lightness) values.

See also: al_color_hsl_to_rgb, al_color_hsv

# al_color_hsl_to_rgb

    void al_color_hsl_to_rgb(float hue, float saturation, float lightness,
       float *red, float *green, float *blue)

Convert values in HSL color model to RGB color model.

Parameters:

- hue - Color hue angle in the range 0..360.
- saturation - Color saturation in the range 0..1.
- lightness - Color lightness in the range 0..1.
- red, green, blue - returned RGB values in the range 0..1.

See also: al_color_rgb_to_hsl, al_color_hsl, al_color_hsv_to_rgb

# al_color_hsv

    ALLEGRO_COLOR al_color_hsv(float h, float s, float v)

Return an ALLEGRO_COLOR structure from HSV (hue, saturation, value) values.

See also: al_color_hsv_to_rgb, al_color_hsl

# al_color_hsv_to_rgb

    void al_color_hsv_to_rgb(float hue, float saturation, float value,
       float *red, float *green, float *blue)

Convert values in HSV color model to RGB color model.

Parameters:

- hue - Color hue angle in the range 0..360.
- saturation - Color saturation in the range 0..1.
- value - Color value in the range 0..1.
- red, green, blue - returned RGB values in the range 0..1.

See also: al_color_rgb_to_hsv, al_color_hsv, al_color_hsl_to_rgb

# al_color_html

    ALLEGRO_COLOR al_color_html(char const *string)

Interprets an HTML styled hex number (e.g. #00faff) as a color. Components that are malformed are set to 0.

See also: al_color_html_to_rgb, al_color_rgb_to_html

# al_color_html_to_rgb

    void al_color_html_to_rgb(char const *string,
       float *red, float *green, float *blue)

Interprets an HTML styled hex number (e.g. #00faff) as a color. Components that are malformed are set to 0.

See also: al_color_html, al_color_rgb_to_html

# al_color_rgb_to_html

    void al_color_rgb_to_html(float red, float green, float blue,
        char *string)

Create an HTML-style string representation of an ALLEGRO_COLOR, e.g. #00faff.

Parameters:

- red, green, blue - The color components in the range 0..1.
- string - A pointer to a buffer of at least 8 bytes, into which the result will be written (including the NUL terminator).

Example:

    char html[8];
    al_color_rgb_to_html(1, 0, 0, html);

Now html will contain "#ff0000".

See also: al_color_html, al_color_html_to_rgb

# al_color_name

    ALLEGRO_COLOR al_color_name(char const *name)

Return an ALLEGRO_COLOR with the given name. If the color is not found then black is returned.

See al_color_name_to_rgb for the list of names.

# al_color_name_to_rgb

    bool al_color_name_to_rgb(char const *name, float *r, float *g, float *b)

Parameters:

- name - The (lowercase) name of the color.
- r, g, b - If one of the recognized color names below is passed, the corresponding RGB values in the range 0..1 are written.

The recognized names are:

> aliceblue, antiquewhite, aqua, aquamarine, azure, beige, bisque, black, blanchedalmond, blue, blueviolet, brown, burlywood, cadetblue, chartreuse, chocolate, coral, cornflowerblue, cornsilk, crimson, cyan, darkblue, darkcyan, darkgoldenrod, darkgray, darkgreen, darkkhaki, darkmagenta, darkolivegreen, darkorange, darkorchid, darkred, darksalmon, darkseagreen, darkslateblue, darkslategray, darkturquoise, darkviolet, deeppink, deepskyblue, dimgray, dodgerblue, firebrick, floralwhite, forestgreen, fuchsia, gainsboro, ghostwhite, goldenrod, gold, gray, green, greenyellow, honeydew, hotpink, indianred, indigo, ivory, khaki, lavenderblush, lavender, lawngreen, lemonchiffon, lightblue, lightcoral, lightcyan, lightgoldenrodyellow, lightgreen, lightgrey, lightpink, lightsalmon, lightseagreen, lightskyblue, lightslategray, lightsteelblue, lightyellow, lime, limegreen, linen, magenta, maroon, mediumaquamarine, mediumblue, mediumorchid, mediumpurple, mediumseagreen, mediumslateblue, mediumspringgreen, mediumturquoise, mediumvioletred, midnightblue, mintcream, mistyrose, moccasin, avajowhite, navy, oldlace, olive, olivedrab, orange, orangered, orchid, palegoldenrod, palegreen, paleturquoise, palevioletred, papayawhip, peachpuff, peru, pink, plum, powderblue, purple, purwablue, red, rosybrown, royalblue, saddlebrown, salmon, sandybrown, seagreen, seashell, sienna, silver, skyblue, slateblue, slategray, snow, springgreen, steelblue, tan, teal, thistle, tomato, turquoise, violet, wheat, white, whitesmoke, yellow, yellowgreen

They are taken from http://www.w3.org/TR/2010/PR-css3-color-20101028/#svg-color.

Returns: true if a name from the list above was passed, else false.

See also: al_color_name

# al_color_rgb_to_cmyk

    void al_color_rgb_to_cmyk(float red, float green, float blue,
       float *cyan, float *magenta, float *yellow, float *key)

Each RGB color can be represented in CMYK with a K component of 0 with the following formula:

    C = 1 - R
    M = 1 - G
    Y = 1 - B
    K = 0

This function will instead find the representation with the maximal value for K and minimal color components.

See also: al_color_cmyk, al_color_cmyk_to_rgb

# al_color_rgb_to_hsl

    void al_color_rgb_to_hsl(float red, float green, float blue,
       float *hue, float *saturation, float *lightness)

Given an RGB triplet with components in the range 0..1, return the hue in degrees from 0..360 and saturation and lightness in the range 0..1.

See also: al_color_hsl_to_rgb, al_color_hsl

# al_color_rgb_to_hsv

    void al_color_rgb_to_hsv(float red, float green, float blue,
       float *hue, float *saturation, float *value)

Given an RGB triplet with components in the range 0..1, return the hue in degrees from 0..360 and saturation and value in the range 0..1.

See also: al_color_hsv_to_rgb, al_color_hsv

# al_color_rgb_to_name

    char const *al_color_rgb_to_name(float r, float g, float b)

Given an RGB triplet with components in the range 0..1, find a color name describing it approximately.

See also: al_color_name_to_rgb, al_color_name

# al_color_rgb_to_yuv

    void al_color_rgb_to_yuv(float red, float green, float blue,
       float *y, float *u, float *v)

Convert RGB values to YUV color space.

See also: al_color_yuv, al_color_yuv_to_rgb

# al_color_yuv

    ALLEGRO_COLOR al_color_yuv(float y, float u, float v)

Return an ALLEGRO_COLOR structure from YUV values.

See also: al_color_yuv_to_rgb, al_color_rgb_to_yuv

# al_color_yuv_to_rgb

    void al_color_yuv_to_rgb(float y, float u, float v,
        float *red, float *green, float *blue)

Convert YUV color values to RGB color space.

See also: al_color_yuv, al_color_rgb_to_yuv

# al_get_allegro_color_version

    uint32_t al_get_allegro_color_version(void)

Returns the (compiled) version of the addon, in the same format as al_get_allegro_version.

Allegro version 5.0.11 - Last updated: 2015-01-12 00:19:44 UTC