diff options
Diffstat (limited to 'libdimension/dimension/color.h')
| -rw-r--r-- | libdimension/dimension/color.h | 98 |
1 files changed, 69 insertions, 29 deletions
diff --git a/libdimension/dimension/color.h b/libdimension/dimension/color.h index 9e47282..393778d 100644 --- a/libdimension/dimension/color.h +++ b/libdimension/dimension/color.h @@ -18,8 +18,9 @@ * <http://www.gnu.org/licenses/>. * *************************************************************************/ -/* - * Types to represent color. +/** + * @file + * Color-related types and operations. */ #ifndef DIMENSION_COLOR_H @@ -27,71 +28,110 @@ #include <stdbool.h> -/* Internally, we use sRGB color. */ +/** A color value. */ typedef struct { - double filter, trans; /* Filter transparancy only lets light of this color - through; regular transparancy lets all colors - through. filter + trans should be <= 1.0. */ - double R, G, B; + /** Filtered transparency. */ + double filter; + /** Unfiltered transparency; <tt>filter + trans</tt> should be <= 1. */ + double trans; + + /* Internally we use sRGB color. */ + double R; /**< @internal sRGB red value. */ + double G; /**< @internal sRGB green value. */ + double B; /**< @internal sRGB blue value. */ } dmnsn_color; +/** sRGB color. */ typedef struct { - double X, Y, Z; /* X, Y, and Z are tristimulus values, unbounded above zero. - Diffuse white is (0.9505, 1, 1.089). */ + double R; /**< sRGB red value. */ + double G; /**< sRGB green value. */ + double B; /**< sRGB blue value. */ +} dmnsn_sRGB; + +/** CIE XYZ color. */ +typedef struct { + double X; /**< X component. */ + double Y; /**< Y (luminance) component. */ + double Z; /**< Z component. */ } dmnsn_CIE_XYZ; +/** CIE xyY color. */ typedef struct { - double x, y, Y; /* x and y are chromaticity coordinates, and Y is luminance, - in the CIE 1931 xyZ color space. We use an unlimited light - model, so x,y in [0, 1] and Y >= 0, with 1 = diffuse - white */ + double x; /**< x chromaticity coordinate (in [0, 1]) */ + double y; /**< y chromaticity coordinate (in [0, 1]) */ + double Y; /**< Luminance, unbounded >= 0; 1 is diffuse white. */ } dmnsn_CIE_xyY; +/** CIE 1976 (L*, a*, b*) color. */ typedef struct { - double L, a, b; /* L is luminence (100 = diffuse white); a and b are color- - opponent dimensions. This color space is used for color - arithmetic. */ + double L; /**< Luminance (100 is diffuse white). */ + double a; /**< Red/greed color-opponent value. */ + double b; /**< Yellow/blue color-opponent value. */ } dmnsn_CIE_Lab; +/** CIE 1976 (L*, u*, v*) color. */ typedef struct { - double L, u, v; /* L is luminence (100 = diffuse white); u and v are - chromaticity coordinates. */ + double L; /**< Luminance (same L* as CIE L*, a*, b*) */ + double u; /**< u* coordinate. */ + double v; /**< v* coordinate. */ } dmnsn_CIE_Luv; -typedef struct { - double R, G, B; /* sRGB R, G, and B values */ -} dmnsn_sRGB; - /* Standard colors */ -extern const dmnsn_color dmnsn_black, dmnsn_white, dmnsn_red, dmnsn_green, - dmnsn_blue, dmnsn_magenta, dmnsn_orange, dmnsn_yellow, dmnsn_cyan; - -/* Standard whitepoint, determined by the conversion of sRGB white to CIE XYZ */ +extern const dmnsn_color dmnsn_black; /**< Black. */ +extern const dmnsn_color dmnsn_white; /**< White. */ +extern const dmnsn_color dmnsn_red; /**< Red. */ +extern const dmnsn_color dmnsn_green; /**< Green. */ +extern const dmnsn_color dmnsn_blue; /**< Blue. */ +extern const dmnsn_color dmnsn_magenta; /**< Magenta. */ +extern const dmnsn_color dmnsn_orange; /**< Orange. */ +extern const dmnsn_color dmnsn_yellow; /**< Yellow. */ +extern const dmnsn_color dmnsn_cyan; /**< Cyan. */ + +/** Standard whitepoint, determined by the conversion of sRGB white to + CIE XYZ */ extern const dmnsn_CIE_XYZ dmnsn_whitepoint; -/* Is this color black? */ +/** Is this color black? */ bool dmnsn_color_is_black(dmnsn_color color); /* Color conversions */ +/** Convert an sRGB color to a Dimension color */ +dmnsn_color dmnsn_color_from_sRGB(dmnsn_sRGB sRGB); +/** Convert a CIE XYZ color to a Dimension color */ dmnsn_color dmnsn_color_from_XYZ(dmnsn_CIE_XYZ XYZ); +/** Convert a CIE xyY color to a Dimension color */ dmnsn_color dmnsn_color_from_xyY(dmnsn_CIE_xyY xyY); +/** Convert a CIE L*, a*, b* color to a Dimension color */ dmnsn_color dmnsn_color_from_Lab(dmnsn_CIE_Lab Lab, dmnsn_CIE_XYZ white); +/** Convert a CIE L*, u*, v* color to a Dimension color */ dmnsn_color dmnsn_color_from_Luv(dmnsn_CIE_Luv Luv, dmnsn_CIE_XYZ white); -dmnsn_color dmnsn_color_from_sRGB(dmnsn_sRGB sRGB); +/** Convert a Dimension color to sRGB */ +dmnsn_sRGB dmnsn_sRGB_from_color(dmnsn_color color); +/** Convert a Dimension color to CIE XYZ */ dmnsn_CIE_XYZ dmnsn_XYZ_from_color(dmnsn_color color); +/** Convert a Dimension color to CIE xyY */ dmnsn_CIE_xyY dmnsn_xyY_from_color(dmnsn_color color); +/** Convert a Dimension color to CIE L*, a*, b* */ dmnsn_CIE_Lab dmnsn_Lab_from_color(dmnsn_color color, dmnsn_CIE_XYZ white); +/** Convert a Dimension color to CIE L*, u*, v* */ dmnsn_CIE_Luv dmnsn_Luv_from_color(dmnsn_color color, dmnsn_CIE_XYZ white); -dmnsn_sRGB dmnsn_sRGB_from_color(dmnsn_color color); /* Perceptual color manipulation */ + +/** Add two colors together */ dmnsn_color dmnsn_color_add(dmnsn_color color1, dmnsn_color color2); +/** Multiply a color's intensity by \p n */ dmnsn_color dmnsn_color_mul(double n, dmnsn_color color); +/** Return the color at \p n on a gradient from \p c1 at 0 to \p c2 at 1 */ dmnsn_color dmnsn_color_gradient(dmnsn_color c1, dmnsn_color c2, double n); +/** Filter \p color through \p filter. */ dmnsn_color dmnsn_color_filter(dmnsn_color color, dmnsn_color filter); +/** Illuminate \p color with \p light. */ dmnsn_color dmnsn_color_illuminate(dmnsn_color light, dmnsn_color color); + +/** Return the perceptual difference between two colors. */ double dmnsn_color_difference(dmnsn_color color1, dmnsn_color color2); #endif /* DIMENSION_COLOR_H */ |