X-Git-Url: http://cgit.sxemacs.org/?a=blobdiff_plain;f=lisp%2Fcolor.el;h=196ec9f8efdc1186f5262a1c799a6af7c7cccd3b;hb=851278bf56a0156a4dd5896e9959f63e33d07ee2;hp=c3f7bee4d0c636099a3914e14cb79510978c2d17;hpb=911b11cfbab776e32e370e7bc7863d7f4ef35c0a;p=gnus diff --git a/lisp/color.el b/lisp/color.el index c3f7bee4d..196ec9f8e 100644 --- a/lisp/color.el +++ b/lisp/color.el @@ -1,9 +1,10 @@ -;;; color.el --- Color manipulation laboratory routines -*- coding: utf-8; -*- +;;; color.el --- Color manipulation library -*- coding: utf-8; -*- -;; Copyright (C) 2010 Free Software Foundation, Inc. +;; Copyright (C) 2010-2015 Free Software Foundation, Inc. -;; Author: Julien Danjou -;; Keywords: html +;; Authors: Julien Danjou +;; Drew Adams +;; Keywords: lisp, faces, color, hex, rgb, hsv, hsl, cie-lab, background ;; This file is part of GNU Emacs. @@ -22,66 +23,136 @@ ;;; Commentary: -;; This package provides color manipulation functions. +;; This package provides functions for manipulating colors, including +;; converting between color representations, computing color +;; complements, and computing CIEDE2000 color distances. +;; +;; Supported color representations include RGB (red, green, blue), HSV +;; (hue, saturation, value), HSL (hue, saturation, luminance), sRGB, +;; CIE XYZ, and CIE L*a*b* color components. ;;; Code: -(eval-when-compile - (require 'cl)) - ;; Emacs < 23.3 (eval-and-compile (unless (boundp 'float-pi) (defconst float-pi (* 4 (atan 1)) "The value of Pi (3.1415926...)."))) -(defun color-rgb->hex (red green blue) - "Return hexadecimal notation for RED GREEN BLUE color. -RED GREEN BLUE must be values between 0 and 1 inclusively." +;;;###autoload +(defun color-name-to-rgb (color &optional frame) + "Convert COLOR string to a list of normalized RGB components. +COLOR should be a color name (e.g. \"white\") or an RGB triplet +string (e.g. \"#ff12ec\"). + +Normally the return value is a list of three floating-point +numbers, (RED GREEN BLUE), each between 0.0 and 1.0 inclusive. + +Optional argument FRAME specifies the frame where the color is to be +displayed. If FRAME is omitted or nil, use the selected frame. +If FRAME cannot display COLOR, return nil." + ;; `colors-values' maximum value is either 65535 or 65280 depending on the + ;; display system. So we use a white conversion to get the max value. + (let ((valmax (float (car (color-values "#ffffff"))))) + (mapcar (lambda (x) (/ x valmax)) (color-values color frame)))) + +(defun color-rgb-to-hex (red green blue) + "Return hexadecimal notation for the color RED GREEN BLUE. +RED, GREEN, and BLUE should be numbers between 0.0 and 1.0, inclusive." (format "#%02x%02x%02x" (* red 255) (* green 255) (* blue 255))) -(defun color-complement (color) - "Return the color that is the complement of COLOR." - (let ((color (color-rgb->normalize color))) - (list (- 1.0 (car color)) - (- 1.0 (cadr color)) - (- 1.0 (caddr color))))) +(defun color-complement (color-name) + "Return the color that is the complement of COLOR-NAME. +COLOR-NAME should be a string naming a color (e.g. \"white\"), or +a string specifying a color's RGB components (e.g. \"#ff12ec\")." + (let ((color (color-name-to-rgb color-name))) + (list (- 1.0 (nth 0 color)) + (- 1.0 (nth 1 color)) + (- 1.0 (nth 2 color))))) + +(defun color-gradient (start stop step-number) + "Return a list with STEP-NUMBER colors from START to STOP. +The color list builds a color gradient starting at color START to +color STOP. It does not include the START and STOP color in the +resulting list." + (let* ((r (nth 0 start)) + (g (nth 1 start)) + (b (nth 2 start)) + (r-step (/ (- (nth 0 stop) r) (1+ step-number))) + (g-step (/ (- (nth 1 stop) g) (1+ step-number))) + (b-step (/ (- (nth 2 stop) b) (1+ step-number))) + result) + (dotimes (n step-number) + (push (list (setq r (+ r r-step)) + (setq g (+ g g-step)) + (setq b (+ b b-step))) + result)) + (nreverse result))) + +(defun color-hue-to-rgb (v1 v2 h) + "Compute hue from V1 and V2 H. +Used internally by `color-hsl-to-rgb'." + (cond + ((< h (/ 1.0 6)) (+ v1 (* (- v2 v1) h 6.0))) + ((< h 0.5) v2) + ((< h (/ 2.0 3)) (+ v1 (* (- v2 v1) (- (/ 2.0 3) h) 6.0))) + (t v1))) + +(defun color-hsl-to-rgb (H S L) + "Convert hue, saturation and luminance to their RGB representation. +H, S, and L should each be numbers between 0.0 and 1.0, inclusive. +Return a list (RED GREEN BLUE), where each element is between 0.0 and 1.0, +inclusive." + (if (= S 0.0) + (list L L L) + (let* ((m2 (if (<= L 0.5) + (* L (+ 1.0 S)) + (- (+ L S) (* L S)))) + (m1 (- (* 2.0 L) m2))) + (list + (color-hue-to-rgb m1 m2 (mod (+ H (/ 1.0 3)) 1)) + (color-hue-to-rgb m1 m2 H) + (color-hue-to-rgb m1 m2 (mod (- H (/ 1.0 3)) 1)))))) (defun color-complement-hex (color) "Return the color that is the complement of COLOR, in hexadecimal format." - (apply 'color-rgb->hex (color-complement color))) + (apply 'color-rgb-to-hex (color-complement color))) -(defun color-rgb->hsv (red green blue) - "Convert RED GREEN BLUE values to HSV representation. -Hue is in radian. Saturation and values are between 0 and 1 -inclusively." - (let* ((r (float red)) +(defun color-rgb-to-hsv (red green blue) + "Convert RGB color components to HSV. +RED, GREEN, and BLUE should each be numbers between 0.0 and 1.0, +inclusive. Return a list (HUE SATURATION VALUE), where HUE is +in radians and both SATURATION and VALUE are between 0.0 and 1.0, +inclusive." + (let* ((r (float red)) (g (float green)) (b (float blue)) (max (max r g b)) (min (min r g b))) - (list - (/ (* 2 float-pi - (cond ((and (= r g) (= g b)) 0) - ((and (= r max) - (>= g b)) - (* 60 (/ (- g b) (- max min)))) - ((and (= r max) - (< g b)) - (+ 360 (* 60 (/ (- g b) (- max min))))) - ((= max g) - (+ 120 (* 60 (/ (- b r) (- max min))))) - ((= max b) - (+ 240 (* 60 (/ (- r g) (- max min))))))) - 360) - (if (= max 0) - 0 - (- 1 (/ min max))) - (/ max 255.0)))) - -(defun color-rgb->hsl (red green blue) - "Convert RED GREEN BLUE colors to their HSL representation. -RED, GREEN and BLUE must be between 0 and 1 inclusively." + (if (< (- max min) 1e-8) + (list 0.0 0.0 min) + (list + (/ (* 2 float-pi + (cond ((and (= r g) (= g b)) 0) + ((and (= r max) + (>= g b)) + (* 60 (/ (- g b) (- max min)))) + ((and (= r max) + (< g b)) + (+ 360 (* 60 (/ (- g b) (- max min))))) + ((= max g) + (+ 120 (* 60 (/ (- b r) (- max min))))) + ((= max b) + (+ 240 (* 60 (/ (- r g) (- max min))))))) + 360) + (if (= max 0) 0 (- 1 (/ min max))) + max)))) + +(defun color-rgb-to-hsl (red green blue) + "Convert RGB colors to their HSL representation. +RED, GREEN, and BLUE should each be numbers between 0.0 and 1.0, +inclusive. Return a list (HUE SATURATION LUMINANCE), where +each element is between 0.0 and 1.0, inclusive." (let* ((r red) (g green) (b blue) @@ -89,27 +160,25 @@ RED, GREEN and BLUE must be between 0 and 1 inclusively." (min (min r g b)) (delta (- max min)) (l (/ (+ max min) 2.0))) - (list - (if (= max min) - 0 - (* 2 float-pi - (/ (cond ((= max r) - (+ (/ (- g b) delta) (if (< g b) 6 0))) - ((= max g) - (+ (/ (- b r) delta) 2)) - (t - (+ (/ (- r g) delta) 4))) - 6))) - (if (= max min) - 0 - (if (> l 0.5) - (/ delta (- 2 (+ max min))) - (/ delta (+ max min)))) - l))) - -(defun color-srgb->xyz (red green blue) - "Converts RED GREEN BLUE colors from the sRGB color space to CIE XYZ. -RED, BLUE and GREEN must be between 0 and 1 inclusively." + (if (= delta 0) + (list 0.0 0.0 l) + (let* ((s (if (<= l 0.5) (/ delta (+ max min)) + (/ delta (- 2.0 max min)))) + (rc (/ (- max r) delta)) + (gc (/ (- max g) delta)) + (bc (/ (- max b) delta)) + (h (mod + (/ + (cond + ((= r max) (- bc gc)) + ((= g max) (+ 2.0 rc (- bc))) + (t (+ 4.0 gc (- rc)))) + 6.0) 1.0))) + (list h s l))))) + +(defun color-srgb-to-xyz (red green blue) + "Convert RED GREEN BLUE colors from the sRGB color space to CIE XYZ. +RED, GREEN and BLUE should be between 0.0 and 1.0, inclusive." (let ((r (if (<= red 0.04045) (/ red 12.95) (expt (/ (+ red 0.055) 1.055) 2.4))) @@ -123,8 +192,8 @@ RED, BLUE and GREEN must be between 0 and 1 inclusively." (+ (* 0.21266729 r) (* 0.7151522 g) (* 0.0721750 b)) (+ (* 0.0193339 r) (* 0.1191920 g) (* 0.9503041 b))))) -(defun color-xyz->srgb (X Y Z) - "Converts CIE X Y Z colors to sRGB color space." +(defun color-xyz-to-srgb (X Y Z) + "Convert CIE X Y Z colors to sRGB color space." (let ((r (+ (* 3.2404542 X) (* -1.5371385 Y) (* -0.4985314 Z))) (g (+ (* -0.9692660 X) (* 1.8760108 Y) (* 0.0415560 Z))) (b (+ (* 0.0556434 X) (* -0.2040259 Y) (* 1.0572252 Z)))) @@ -144,10 +213,10 @@ RED, BLUE and GREEN must be between 0 and 1 inclusively." (defconst color-cie-ε (/ 216 24389.0)) (defconst color-cie-κ (/ 24389 27.0)) -(defun color-xyz->lab (X Y Z &optional white-point) - "Converts CIE XYZ to CIE L*a*b*. -WHITE-POINT can be specified as (X Y Z) white point to use. If -none is set, `color-d65-xyz' is used." +(defun color-xyz-to-lab (X Y Z &optional white-point) + "Convert CIE XYZ to CIE L*a*b*. +WHITE-POINT specifies the (X Y Z) white point for the +conversion. If omitted or nil, use `color-d65-xyz'." (destructuring-bind (Xr Yr Zr) (or white-point color-d65-xyz) (let* ((xr (/ X Xr)) (yr (/ Y Yr)) @@ -166,10 +235,10 @@ none is set, `color-d65-xyz' is used." (* 500 (- fx fy)) ; a (* 200 (- fy fz)))))) ; b -(defun color-lab->xyz (L a b &optional white-point) - "Converts CIE L*a*b* to CIE XYZ. -WHITE-POINT can be specified as (X Y Z) white point to use. If -none is set, `color-d65-xyz' is used." +(defun color-lab-to-xyz (L a b &optional white-point) + "Convert CIE L*a*b* to CIE XYZ. +WHITE-POINT specifies the (X Y Z) white point for the +conversion. If omitted or nil, use `color-d65-xyz'." (destructuring-bind (Xr Yr Zr) (or white-point color-d65-xyz) (let* ((fy (/ (+ L 16) 116.0)) (fz (- fy (/ b 200.0))) @@ -187,21 +256,18 @@ none is set, `color-d65-xyz' is used." (* yr Yr) ; Y (* zr Zr))))) ; Z -(defun color-srgb->lab (red green blue) - "Converts RGB to CIE L*a*b*." - (apply 'color-xyz->lab (color-srgb->xyz red green blue))) - -(defun color-rgb->normalize (color) - "Normalize a RGB color to values between 0 and 1 inclusively." - (mapcar (lambda (x) (/ x 65535.0)) (x-color-values color))) +(defun color-srgb-to-lab (red green blue) + "Convert RGB to CIE L*a*b*." + (apply 'color-xyz-to-lab (color-srgb-to-xyz red green blue))) -(defun color-lab->srgb (L a b) - "Converts CIE L*a*b* to RGB." - (apply 'color-xyz->srgb (color-lab->xyz L a b))) +(defun color-lab-to-srgb (L a b) + "Convert CIE L*a*b* to RGB." + (apply 'color-xyz-to-srgb (color-lab-to-xyz L a b))) (defun color-cie-de2000 (color1 color2 &optional kL kC kH) - "Computes the CIEDE2000 color distance between COLOR1 and COLOR2. -Colors must be in CIE L*a*b* format." + "Return the CIEDE2000 color distance between COLOR1 and COLOR2. +Both COLOR1 and COLOR2 should be in CIE L*a*b* format, as +returned by `color-srgb-to-lab' or `color-xyz-to-lab'." (destructuring-bind (L₁ a₁ b₁) color1 (destructuring-bind (L₂ a₂ b₂) color2 (let* ((kL (or kL 1)) @@ -264,6 +330,70 @@ Colors must be in CIE L*a*b* format." (expt (/ ΔH′ (* Sh kH)) 2.0) (* Rt (/ ΔC′ (* Sc kC)) (/ ΔH′ (* Sh kH))))))))) +(defun color-clamp (value) + "Make sure VALUE is a number between 0.0 and 1.0 inclusive." + (min 1.0 (max 0.0 value))) + +(defun color-saturate-hsl (H S L percent) + "Make a color more saturated by a specified amount. +Given a color defined in terms of hue, saturation, and luminance +\(arguments H, S, and L), return a color that is PERCENT more +saturated. Returns a list (HUE SATURATION LUMINANCE)." + (list H (color-clamp (+ S (/ percent 100.0))) L)) + +(defun color-saturate-name (name percent) + "Make a color with a specified NAME more saturated by PERCENT. +See `color-saturate-hsl'." + (apply 'color-rgb-to-hex + (apply 'color-hsl-to-rgb + (apply 'color-saturate-hsl + (append + (apply 'color-rgb-to-hsl + (color-name-to-rgb name)) + (list percent)))))) + +(defun color-desaturate-hsl (H S L percent) + "Make a color less saturated by a specified amount. +Given a color defined in terms of hue, saturation, and luminance +\(arguments H, S, and L), return a color that is PERCENT less +saturated. Returns a list (HUE SATURATION LUMINANCE)." + (color-saturate-hsl H S L (- percent))) + +(defun color-desaturate-name (name percent) + "Make a color with a specified NAME less saturated by PERCENT. +See `color-desaturate-hsl'." + (color-saturate-name name (- percent))) + +(defun color-lighten-hsl (H S L percent) + "Make a color lighter by a specified amount. +Given a color defined in terms of hue, saturation, and luminance +\(arguments H, S, and L), return a color that is PERCENT lighter. +Returns a list (HUE SATURATION LUMINANCE)." + (list H S (color-clamp (+ L (/ percent 100.0))))) + +(defun color-lighten-name (name percent) + "Make a color with a specified NAME lighter by PERCENT. +See `color-lighten-hsl'." + (apply 'color-rgb-to-hex + (apply 'color-hsl-to-rgb + (apply 'color-lighten-hsl + (append + (apply 'color-rgb-to-hsl + (color-name-to-rgb name)) + (list percent)))))) + +(defun color-darken-hsl (H S L percent) + "Make a color darker by a specified amount. +Given a color defined in terms of hue, saturation, and luminance +\(arguments H, S, and L), return a color that is PERCENT darker. +Returns a list (HUE SATURATION LUMINANCE)." + (color-lighten-hsl H S L (- percent))) + +(defun color-darken-name (name percent) + "Make a color with a specified NAME darker by PERCENT. +See `color-darken-hsl'." + (color-lighten-name name (- percent))) + (provide 'color) ;;; color.el ends here