gagbo/colorstrans.el

## colorstrans.el
;;; colortrans.el --- simple conversion tool between truecolor and xterm
;; -*- coding: utf-8; lexical-binding: t; -*-

;; Copyright © 2019, by Gerry Agbobada

;; Author: Gerry Agbobada ( gagbobada+git@gmail.com )
;; Version: 0.0.1
;; Created: 09 May 2019
;; Keywords: color

;; This file is not part of GNU Emacs.

;;; License:
;; You can redistribute this program and/or modify it under the terms of the MIT License

;;; Commentary:
;; We avoid defined-colors to convert to xterm because it does not have
;; only xterm palette colors (see M-x list-colors-display)

;;; Code:
(require 'color)
(require 'cl-macs)
(require 'dash)


(defun colortrans--normalize-rgb (rgb_int_val)
  "Return RGB_INT_VAL scaled from 0-255 to 0-1.0.
   Values are truncated to the thousandth."
  (let ((truncator 0.0009765625)
	(max_rgb_val 255.0))
    (* (truncate (/ rgb_int_val max_rgb_val) truncator) truncator)))

(defun colortrans--hsv-distance (col1 col2)
  "FAILS BECAUSE HUE DOES NOT WRAP AROUND !
Return an estimation of the distance between COL1 and COL2."
  ;; FIXME: hue does not wrap around so it gives wrong results
  (let* ((norm_exponents '(2 2 1))
	 (col_diff (--zip-with (abs (- it other))
			       (append col1 nil)
			       (append col2 nil)))
	 )
    (-sum (--zip-with (expt it other) col_diff norm_exponents)))
  )

(defun colortrans-hex-to-vec (rrggbb)
  "Convert color *rrggbb from “\"rrggbb\"” string to a elisp vector [r g b], where the values are from 0 to 1.

Note: The input string must NOT start with “#”."
  (vector
   (colortrans--normalize-rgb (string-to-number (substring rrggbb 0 2) 16))
   (colortrans--normalize-rgb (string-to-number (substring rrggbb 2 4) 16))
   (colortrans--normalize-rgb (string-to-number (substring rrggbb 4) 16))))

(defun colortrans-vec-rgb-to-vec-hsv (rgb_comp)
  "Convert a color reprensented by [r g b] vector RGB_COMP to
[h s v] hue saturation value vector."
  (vconcat (color-rgb-to-hsv
	    (aref rgb_comp 0)
	    (aref rgb_comp 1)
	    (aref rgb_comp 2))))

(setq colortrans--xtermlut
      `(("color-16" . ,(vector 0  0  0))
	("color-17" . ,(vector 0  0  95))
	("color-18" . ,(vector 0  0  135))
	("color-19" . ,(vector 0  0  175))
	("color-20" . ,(vector 0  0  215))
	("color-21" . ,(vector 0  0  255))
	("color-22" . ,(vector 0  95  0))
	("color-23" . ,(vector 0  95  95))
	("color-24" . ,(vector 0  95  135))
	("color-25" . ,(vector 0  95  175))
	("color-26" . ,(vector 0  95  215))
	("color-27" . ,(vector 0  95  255))
	("color-28" . ,(vector 0  135  0))
	("color-29" . ,(vector 0  135  95))
	("color-30" . ,(vector 0  135  135))
	("color-31" . ,(vector 0  135  175))
	("color-32" . ,(vector 0  135  215))
	("color-33" . ,(vector 0  135  255))
	("color-34" . ,(vector 0  175  0))
	("color-35" . ,(vector 0  175  95))
	("color-36" . ,(vector 0  175  135))
	("color-37" . ,(vector 0  175  175))
	("color-38" . ,(vector 0  175  215))
	("color-39" . ,(vector 0  175  255))
	("color-40" . ,(vector 0  215  0))
	("color-41" . ,(vector 0  215  95))
	("color-42" . ,(vector 0  215  135))
	("color-43" . ,(vector 0  215  175))
	("color-44" . ,(vector 0  215  215))
	("color-45" . ,(vector 0  215  255))
	("color-46" . ,(vector 0  255  0))
	("color-47" . ,(vector 0  255  95))
	("color-48" . ,(vector 0  255  135))
	("color-49" . ,(vector 0  255  175))
	("color-50" . ,(vector 0  255  215))
	("color-51" . ,(vector 0  255  255))
	("color-52" . ,(vector 95  0  0))
	("color-53" . ,(vector 95  0  95))
	("color-54" . ,(vector 95  0  135))
	("color-55" . ,(vector 95  0  175))
	("color-56" . ,(vector 95  0  215))
	("color-57" . ,(vector 95  0  255))
	("color-58" . ,(vector 95  95  0))
	("color-59" . ,(vector 95  95  95))
	("color-60" . ,(vector 95  95  135))
	("color-61" . ,(vector 95  95  175))
	("color-62" . ,(vector 95  95  215))
	("color-63" . ,(vector 95  95  255))
	("color-64" . ,(vector 95  135  0))
	("color-65" . ,(vector 95  135  95))
	("color-66" . ,(vector 95  135  135))
	("color-67" . ,(vector 95  135  175))
	("color-68" . ,(vector 95  135  215))
	("color-69" . ,(vector 95  135  255))
	("color-70" . ,(vector 95  175  0))
	("color-71" . ,(vector 95  175  95))
	("color-72" . ,(vector 95  175  135))
	("color-73" . ,(vector 95  175  175))
	("color-74" . ,(vector 95  175  215))
	("color-75" . ,(vector 95  175  255))
	("color-76" . ,(vector 95  215  0))
	("color-77" . ,(vector 95  215  95))
	("color-78" . ,(vector 95  215  135))
	("color-79" . ,(vector 95  215  175))
	("color-80" . ,(vector 95  215  215))
	("color-81" . ,(vector 95  215  255))
	("color-82" . ,(vector 95  255  0))
	("color-83" . ,(vector 95  255  95))
	("color-84" . ,(vector 95  255  135))
	("color-85" . ,(vector 95  255  175))
	("color-86" . ,(vector 95  255  215))
	("color-87" . ,(vector 95  255  255))
	("color-88" . ,(vector 135  0  0))
	("color-89" . ,(vector 135  0  95))
	("color-90" . ,(vector 135  0  135))
	("color-91" . ,(vector 135  0  175))
	("color-92" . ,(vector 135  0  215))
	("color-93" . ,(vector 135  0  255))
	("color-94" . ,(vector 135  95  0))
	("color-95" . ,(vector 135  95  95))
	("color-96" . ,(vector 135  95  135))
	("color-97" . ,(vector 135  95  175))
	("color-98" . ,(vector 135  95  215))
	("color-99" . ,(vector 135  95  255))
	("color-100" . ,(vector 135  135  0))
	("color-101" . ,(vector 135  135  95))
	("color-102" . ,(vector 135  135  135))
	("color-103" . ,(vector 135  135  175))
	("color-104" . ,(vector 135  135  215))
	("color-105" . ,(vector 135  135  255))
	("color-106" . ,(vector 135  175  0))
	("color-107" . ,(vector 135  175  95))
	("color-108" . ,(vector 135  175  135))
	("color-109" . ,(vector 135  175  175))
	("color-110" . ,(vector 135  175  215))
	("color-111" . ,(vector 135  175  255))
	("color-112" . ,(vector 135  215  0))
	("color-113" . ,(vector 135  215  95))
	("color-114" . ,(vector 135  215  135))
	("color-115" . ,(vector 135  215  175))
	("color-116" . ,(vector 135  215  215))
	("color-117" . ,(vector 135  215  255))
	("color-118" . ,(vector 135  255  0))
	("color-119" . ,(vector 135  255  95))
	("color-120" . ,(vector 135  255  135))
	("color-121" . ,(vector 135  255  175))
	("color-122" . ,(vector 135  255  215))
	("color-123" . ,(vector 135  255  255))
	("color-124" . ,(vector 175  0  0))
	("color-125" . ,(vector 175  0  95))
	("color-126" . ,(vector 175  0  135))
	("color-127" . ,(vector 175  0  175))
	("color-128" . ,(vector 175  0  215))
	("color-129" . ,(vector 175  0  255))
	("color-130" . ,(vector 175  95  0))
	("color-131" . ,(vector 175  95  95))
	("color-132" . ,(vector 175  95  135))
	("color-133" . ,(vector 175  95  175))
	("color-134" . ,(vector 175  95  215))
	("color-135" . ,(vector 175  95  255))
	("color-136" . ,(vector 175  135  0))
	("color-137" . ,(vector 175  135  95))
	("color-138" . ,(vector 175  135  135))
	("color-139" . ,(vector 175  135  175))
	("color-140" . ,(vector 175  135  215))
	("color-141" . ,(vector 175  135  255))
	("color-142" . ,(vector 175  175  0))
	("color-143" . ,(vector 175  175  95))
	("color-144" . ,(vector 175  175  135))
	("color-145" . ,(vector 175  175  175))
	("color-146" . ,(vector 175  175  215))
	("color-147" . ,(vector 175  175  255))
	("color-148" . ,(vector 175  215  0))
	("color-149" . ,(vector 175  215  95))
	("color-150" . ,(vector 175  215  135))
	("color-151" . ,(vector 175  215  175))
	("color-152" . ,(vector 175  215  215))
	("color-153" . ,(vector 175  215  255))
	("color-154" . ,(vector 175  255  0))
	("color-155" . ,(vector 175  255  95))
	("color-156" . ,(vector 175  255  135))
	("color-157" . ,(vector 175  255  175))
	("color-158" . ,(vector 175  255  215))
	("color-159" . ,(vector 175  255  255))
	("color-160" . ,(vector 215  0  0))
	("color-161" . ,(vector 215  0  95))
	("color-162" . ,(vector 215  0  135))
	("color-163" . ,(vector 215  0  175))
	("color-164" . ,(vector 215  0  215))
	("color-165" . ,(vector 215  0  255))
	("color-166" . ,(vector 215  95  0))
	("color-167" . ,(vector 215  95  95))
	("color-168" . ,(vector 215  95  135))
	("color-169" . ,(vector 215  95  175))
	("color-170" . ,(vector 215  95  215))
	("color-171" . ,(vector 215  95  255))
	("color-172" . ,(vector 215  135  0))
	("color-173" . ,(vector 215  135  95))
	("color-174" . ,(vector 215  135  135))
	("color-175" . ,(vector 215  135  175))
	("color-176" . ,(vector 215  135  215))
	("color-177" . ,(vector 215  135  255))
	("color-178" . ,(vector 215  175  0))
	("color-179" . ,(vector 215  175  95))
	("color-180" . ,(vector 215  175  135))
	("color-181" . ,(vector 215  175  175))
	("color-182" . ,(vector 215  175  215))
	("color-183" . ,(vector 215  175  255))
	("color-184" . ,(vector 215  215  0))
	("color-185" . ,(vector 215  215  95))
	("color-186" . ,(vector 215  215  135))
	("color-187" . ,(vector 215  215  175))
	("color-188" . ,(vector 215  215  215))
	("color-189" . ,(vector 215  215  255))
	("color-190" . ,(vector 215  255  0))
	("color-191" . ,(vector 215  255  95))
	("color-192" . ,(vector 215  255  135))
	("color-193" . ,(vector 215  255  175))
	("color-194" . ,(vector 215  255  215))
	("color-195" . ,(vector 215  255  255))
	("color-196" . ,(vector 255  0  0))
	("color-197" . ,(vector 255  0  95))
	("color-198" . ,(vector 255  0  135))
	("color-199" . ,(vector 255  0  175))
	("color-200" . ,(vector 255  0  215))
	("color-201" . ,(vector 255  0  255))
	("color-202" . ,(vector 255  95  0))
	("color-203" . ,(vector 255  95  95))
	("color-204" . ,(vector 255  95  135))
	("color-205" . ,(vector 255  95  175))
	("color-206" . ,(vector 255  95  215))
	("color-207" . ,(vector 255  95  255))
	("color-208" . ,(vector 255  135  0))
	("color-209" . ,(vector 255  135  95))
	("color-210" . ,(vector 255  135  135))
	("color-211" . ,(vector 255  135  175))
	("color-212" . ,(vector 255  135  215))
	("color-213" . ,(vector 255  135  255))
	("color-214" . ,(vector 255  175  0))
	("color-215" . ,(vector 255  175  95))
	("color-216" . ,(vector 255  175  135))
	("color-217" . ,(vector 255  175  175))
	("color-218" . ,(vector 255  175  215))
	("color-219" . ,(vector 255  175  255))
	("color-220" . ,(vector 255  215  0))
	("color-221" . ,(vector 255  215  95))
	("color-222" . ,(vector 255  215  135))
	("color-223" . ,(vector 255  215  175))
	("color-224" . ,(vector 255  215  215))
	("color-225" . ,(vector 255  215  255))
	("color-226" . ,(vector 255  255  0))
	("color-227" . ,(vector 255  255  95))
	("color-228" . ,(vector 255  255  135))
	("color-229" . ,(vector 255  255  175))
	("color-230" . ,(vector 255  255  215))
	("color-231" . ,(vector 255  255  255))
	;; Gray-scale range.
	("color-232" . ,(vector 8 8 8))
	("color-233" . ,(vector 18 18 18))
	("color-234" . ,(vector 28 28 28))
	("color-235" . ,(vector 38 38 38))
	("color-236" . ,(vector 48 48 48))
	("color-237" . ,(vector 58 58 58))
	("color-238" . ,(vector 68 68 68))
	("color-239" . ,(vector 78 78 78))
	("color-240" . ,(vector 88 88 88))
	("color-241" . ,(vector 98 98 98))
	("color-242" . ,(vector 108 108 108))
	("color-243" . ,(vector 118 118 118))
	("color-244" . ,(vector 128 128 128))
	("color-245" . ,(vector 138 138 138))
	("color-246" . ,(vector 148 148 148))
	("color-247" . ,(vector 158 158 158))
	("color-248" . ,(vector 168 168 168))
	("color-249" . ,(vector 178 178 178))
	("color-250" . ,(vector 188 188 188))
	("color-251" . ,(vector 198 198 198))
	("color-252" . ,(vector 208 208 208))
	("color-253" . ,(vector 218 218 218))
	("color-254" . ,(vector 228 228 228))
	("color-255" . ,(vector 238 238 238))))

(setq colortrans--clut
      (cl-loop for (key . value) in colortrans--xtermlut
	       collect (cons key (vconcat (mapcar 'colortrans--normalize-rgb value)))))

(defun colortrans--closest-to-hex-in-alist (rrggbb candidates)
  "Returns the closest color to RRGGBB (in 24-bit hex string format)
in CANDIDATES.

CANDIDATES must be an alist with descriptive names as keys, and a vector
[r g b] as value (r g b in interval [0, 1]).

Note: RRGGBB must NOT start with a '#'"
  (let* ((hsv_target (colortrans-vec-rgb-to-vec-hsv
		      (colortrans-hex-to-vec rrggbb))))
    (--min-by
     (> (colortrans--hsv-distance hsv_target
				  (colortrans-vec-rgb-to-vec-hsv (cdr it)))
	(colortrans--hsv-distance hsv_target
				  (colortrans-vec-rgb-to-vec-hsv (cdr other))))
     candidates)))

(defun colortrans-hex-to-xterm (rrggbb)
  "FAILS BECAUSE HUE DOES NOT WRAP AROUND !
Give color “\"rrggbb\"” string's closest xterm palette counterpart.

Note: The input string must NOT start with “#”."
  (interactive "sColor to translate: ")
  (colortrans--closest-to-hex-in-alist rrggbb colortrans--clut))

(defun colortrans-hex-to-name (rrggbb)
  "FAILS BECAUSE HUE DOES NOT WRAP AROUND !
Give color “\"rrggbb\"” string's closest named color counterpart.

Note: The input string must NOT start with “#”."
  (interactive "sColor to translate: ")
  (let* ((named_colors (cl-loop for col_name in (defined-colors)
				collect (cons col_name (vconcat (color-name-to-rgb col_name))))))
    (colortrans--closest-to-hex-in-alist rrggbb named_colors)
    ))

(provide 'colortrans)

;;; colortrans.el ends here
	;;; colortrans.el --- simple conversion tool between truecolor and xterm
	;; -- coding: utf-8; lexical-binding: t; --

	;; Copyright © 2019, by Gerry Agbobada

	;; Author: Gerry Agbobada ( gagbobada+git@gmail.com )
	;; Version: 0.0.1
	;; Created: 09 May 2019
	;; Keywords: color

	;; This file is not part of GNU Emacs.

	;;; License:
	;; You can redistribute this program and/or modify it under the terms of the MIT License

	;;; Commentary:
	;; We avoid defined-colors to convert to xterm because it does not have
	;; only xterm palette colors (see M-x list-colors-display)

	;;; Code:
	(require 'color)
	(require 'cl-macs)
	(require 'dash)


	(defun colortrans--normalize-rgb (rgb_int_val)
	"Return RGB_INT_VAL scaled from 0-255 to 0-1.0.
	Values are truncated to the thousandth."
	(let ((truncator 0.0009765625)
	(max_rgb_val 255.0))
	(* (truncate (/ rgb_int_val max_rgb_val) truncator) truncator)))

	(defun colortrans--hsv-distance (col1 col2)
	"FAILS BECAUSE HUE DOES NOT WRAP AROUND !
	Return an estimation of the distance between COL1 and COL2."
	;; FIXME: hue does not wrap around so it gives wrong results
	(let* ((norm_exponents '(2 2 1))
	(col_diff (--zip-with (abs (- it other))
	(append col1 nil)
	(append col2 nil)))
	)
	(-sum (--zip-with (expt it other) col_diff norm_exponents)))
	)

	(defun colortrans-hex-to-vec (rrggbb)
	"Convert color *rrggbb from “\"rrggbb\"” string to a elisp vector [r g b], where the values are from 0 to 1.

	Note: The input string must NOT start with “#”."
	(vector
	(colortrans--normalize-rgb (string-to-number (substring rrggbb 0 2) 16))
	(colortrans--normalize-rgb (string-to-number (substring rrggbb 2 4) 16))
	(colortrans--normalize-rgb (string-to-number (substring rrggbb 4) 16))))

	(defun colortrans-vec-rgb-to-vec-hsv (rgb_comp)
	"Convert a color reprensented by [r g b] vector RGB_COMP to
	[h s v] hue saturation value vector."
	(vconcat (color-rgb-to-hsv
	(aref rgb_comp 0)
	(aref rgb_comp 1)
	(aref rgb_comp 2))))

	(setq colortrans--xtermlut
	`(("color-16" . ,(vector 0 0 0))
	("color-17" . ,(vector 0 0 95))
	("color-18" . ,(vector 0 0 135))
	("color-19" . ,(vector 0 0 175))
	("color-20" . ,(vector 0 0 215))
	("color-21" . ,(vector 0 0 255))
	("color-22" . ,(vector 0 95 0))
	("color-23" . ,(vector 0 95 95))
	("color-24" . ,(vector 0 95 135))
	("color-25" . ,(vector 0 95 175))
	("color-26" . ,(vector 0 95 215))
	("color-27" . ,(vector 0 95 255))
	("color-28" . ,(vector 0 135 0))
	("color-29" . ,(vector 0 135 95))
	("color-30" . ,(vector 0 135 135))
	("color-31" . ,(vector 0 135 175))
	("color-32" . ,(vector 0 135 215))
	("color-33" . ,(vector 0 135 255))
	("color-34" . ,(vector 0 175 0))
	("color-35" . ,(vector 0 175 95))
	("color-36" . ,(vector 0 175 135))
	("color-37" . ,(vector 0 175 175))
	("color-38" . ,(vector 0 175 215))
	("color-39" . ,(vector 0 175 255))
	("color-40" . ,(vector 0 215 0))
	("color-41" . ,(vector 0 215 95))
	("color-42" . ,(vector 0 215 135))
	("color-43" . ,(vector 0 215 175))
	("color-44" . ,(vector 0 215 215))
	("color-45" . ,(vector 0 215 255))
	("color-46" . ,(vector 0 255 0))
	("color-47" . ,(vector 0 255 95))
	("color-48" . ,(vector 0 255 135))
	("color-49" . ,(vector 0 255 175))
	("color-50" . ,(vector 0 255 215))
	("color-51" . ,(vector 0 255 255))
	("color-52" . ,(vector 95 0 0))
	("color-53" . ,(vector 95 0 95))
	("color-54" . ,(vector 95 0 135))
	("color-55" . ,(vector 95 0 175))
	("color-56" . ,(vector 95 0 215))
	("color-57" . ,(vector 95 0 255))
	("color-58" . ,(vector 95 95 0))
	("color-59" . ,(vector 95 95 95))
	("color-60" . ,(vector 95 95 135))
	("color-61" . ,(vector 95 95 175))
	("color-62" . ,(vector 95 95 215))
	("color-63" . ,(vector 95 95 255))
	("color-64" . ,(vector 95 135 0))
	("color-65" . ,(vector 95 135 95))
	("color-66" . ,(vector 95 135 135))
	("color-67" . ,(vector 95 135 175))
	("color-68" . ,(vector 95 135 215))
	("color-69" . ,(vector 95 135 255))
	("color-70" . ,(vector 95 175 0))
	("color-71" . ,(vector 95 175 95))
	("color-72" . ,(vector 95 175 135))
	("color-73" . ,(vector 95 175 175))
	("color-74" . ,(vector 95 175 215))
	("color-75" . ,(vector 95 175 255))
	("color-76" . ,(vector 95 215 0))
	("color-77" . ,(vector 95 215 95))
	("color-78" . ,(vector 95 215 135))
	("color-79" . ,(vector 95 215 175))
	("color-80" . ,(vector 95 215 215))
	("color-81" . ,(vector 95 215 255))
	("color-82" . ,(vector 95 255 0))
	("color-83" . ,(vector 95 255 95))
	("color-84" . ,(vector 95 255 135))
	("color-85" . ,(vector 95 255 175))
	("color-86" . ,(vector 95 255 215))
	("color-87" . ,(vector 95 255 255))
	("color-88" . ,(vector 135 0 0))
	("color-89" . ,(vector 135 0 95))
	("color-90" . ,(vector 135 0 135))
	("color-91" . ,(vector 135 0 175))
	("color-92" . ,(vector 135 0 215))
	("color-93" . ,(vector 135 0 255))
	("color-94" . ,(vector 135 95 0))
	("color-95" . ,(vector 135 95 95))
	("color-96" . ,(vector 135 95 135))
	("color-97" . ,(vector 135 95 175))
	("color-98" . ,(vector 135 95 215))
	("color-99" . ,(vector 135 95 255))
	("color-100" . ,(vector 135 135 0))
	("color-101" . ,(vector 135 135 95))
	("color-102" . ,(vector 135 135 135))
	("color-103" . ,(vector 135 135 175))
	("color-104" . ,(vector 135 135 215))
	("color-105" . ,(vector 135 135 255))
	("color-106" . ,(vector 135 175 0))
	("color-107" . ,(vector 135 175 95))
	("color-108" . ,(vector 135 175 135))
	("color-109" . ,(vector 135 175 175))
	("color-110" . ,(vector 135 175 215))
	("color-111" . ,(vector 135 175 255))
	("color-112" . ,(vector 135 215 0))
	("color-113" . ,(vector 135 215 95))
	("color-114" . ,(vector 135 215 135))
	("color-115" . ,(vector 135 215 175))
	("color-116" . ,(vector 135 215 215))
	("color-117" . ,(vector 135 215 255))
	("color-118" . ,(vector 135 255 0))
	("color-119" . ,(vector 135 255 95))
	("color-120" . ,(vector 135 255 135))
	("color-121" . ,(vector 135 255 175))
	("color-122" . ,(vector 135 255 215))
	("color-123" . ,(vector 135 255 255))
	("color-124" . ,(vector 175 0 0))
	("color-125" . ,(vector 175 0 95))
	("color-126" . ,(vector 175 0 135))
	("color-127" . ,(vector 175 0 175))
	("color-128" . ,(vector 175 0 215))
	("color-129" . ,(vector 175 0 255))
	("color-130" . ,(vector 175 95 0))
	("color-131" . ,(vector 175 95 95))
	("color-132" . ,(vector 175 95 135))
	("color-133" . ,(vector 175 95 175))
	("color-134" . ,(vector 175 95 215))
	("color-135" . ,(vector 175 95 255))
	("color-136" . ,(vector 175 135 0))
	("color-137" . ,(vector 175 135 95))
	("color-138" . ,(vector 175 135 135))
	("color-139" . ,(vector 175 135 175))
	("color-140" . ,(vector 175 135 215))
	("color-141" . ,(vector 175 135 255))
	("color-142" . ,(vector 175 175 0))
	("color-143" . ,(vector 175 175 95))
	("color-144" . ,(vector 175 175 135))
	("color-145" . ,(vector 175 175 175))
	("color-146" . ,(vector 175 175 215))
	("color-147" . ,(vector 175 175 255))
	("color-148" . ,(vector 175 215 0))
	("color-149" . ,(vector 175 215 95))
	("color-150" . ,(vector 175 215 135))
	("color-151" . ,(vector 175 215 175))
	("color-152" . ,(vector 175 215 215))
	("color-153" . ,(vector 175 215 255))
	("color-154" . ,(vector 175 255 0))
	("color-155" . ,(vector 175 255 95))
	("color-156" . ,(vector 175 255 135))
	("color-157" . ,(vector 175 255 175))
	("color-158" . ,(vector 175 255 215))
	("color-159" . ,(vector 175 255 255))
	("color-160" . ,(vector 215 0 0))
	("color-161" . ,(vector 215 0 95))
	("color-162" . ,(vector 215 0 135))
	("color-163" . ,(vector 215 0 175))
	("color-164" . ,(vector 215 0 215))
	("color-165" . ,(vector 215 0 255))
	("color-166" . ,(vector 215 95 0))
	("color-167" . ,(vector 215 95 95))
	("color-168" . ,(vector 215 95 135))
	("color-169" . ,(vector 215 95 175))
	("color-170" . ,(vector 215 95 215))
	("color-171" . ,(vector 215 95 255))
	("color-172" . ,(vector 215 135 0))
	("color-173" . ,(vector 215 135 95))
	("color-174" . ,(vector 215 135 135))
	("color-175" . ,(vector 215 135 175))
	("color-176" . ,(vector 215 135 215))
	("color-177" . ,(vector 215 135 255))
	("color-178" . ,(vector 215 175 0))
	("color-179" . ,(vector 215 175 95))
	("color-180" . ,(vector 215 175 135))
	("color-181" . ,(vector 215 175 175))
	("color-182" . ,(vector 215 175 215))
	("color-183" . ,(vector 215 175 255))
	("color-184" . ,(vector 215 215 0))
	("color-185" . ,(vector 215 215 95))
	("color-186" . ,(vector 215 215 135))
	("color-187" . ,(vector 215 215 175))
	("color-188" . ,(vector 215 215 215))
	("color-189" . ,(vector 215 215 255))
	("color-190" . ,(vector 215 255 0))
	("color-191" . ,(vector 215 255 95))
	("color-192" . ,(vector 215 255 135))
	("color-193" . ,(vector 215 255 175))
	("color-194" . ,(vector 215 255 215))
	("color-195" . ,(vector 215 255 255))
	("color-196" . ,(vector 255 0 0))
	("color-197" . ,(vector 255 0 95))
	("color-198" . ,(vector 255 0 135))
	("color-199" . ,(vector 255 0 175))
	("color-200" . ,(vector 255 0 215))
	("color-201" . ,(vector 255 0 255))
	("color-202" . ,(vector 255 95 0))
	("color-203" . ,(vector 255 95 95))
	("color-204" . ,(vector 255 95 135))
	("color-205" . ,(vector 255 95 175))
	("color-206" . ,(vector 255 95 215))
	("color-207" . ,(vector 255 95 255))
	("color-208" . ,(vector 255 135 0))
	("color-209" . ,(vector 255 135 95))
	("color-210" . ,(vector 255 135 135))
	("color-211" . ,(vector 255 135 175))
	("color-212" . ,(vector 255 135 215))
	("color-213" . ,(vector 255 135 255))
	("color-214" . ,(vector 255 175 0))
	("color-215" . ,(vector 255 175 95))
	("color-216" . ,(vector 255 175 135))
	("color-217" . ,(vector 255 175 175))
	("color-218" . ,(vector 255 175 215))
	("color-219" . ,(vector 255 175 255))
	("color-220" . ,(vector 255 215 0))
	("color-221" . ,(vector 255 215 95))
	("color-222" . ,(vector 255 215 135))
	("color-223" . ,(vector 255 215 175))
	("color-224" . ,(vector 255 215 215))
	("color-225" . ,(vector 255 215 255))
	("color-226" . ,(vector 255 255 0))
	("color-227" . ,(vector 255 255 95))
	("color-228" . ,(vector 255 255 135))
	("color-229" . ,(vector 255 255 175))
	("color-230" . ,(vector 255 255 215))
	("color-231" . ,(vector 255 255 255))
	;; Gray-scale range.
	("color-232" . ,(vector 8 8 8))
	("color-233" . ,(vector 18 18 18))
	("color-234" . ,(vector 28 28 28))
	("color-235" . ,(vector 38 38 38))
	("color-236" . ,(vector 48 48 48))
	("color-237" . ,(vector 58 58 58))
	("color-238" . ,(vector 68 68 68))
	("color-239" . ,(vector 78 78 78))
	("color-240" . ,(vector 88 88 88))
	("color-241" . ,(vector 98 98 98))
	("color-242" . ,(vector 108 108 108))
	("color-243" . ,(vector 118 118 118))
	("color-244" . ,(vector 128 128 128))
	("color-245" . ,(vector 138 138 138))
	("color-246" . ,(vector 148 148 148))
	("color-247" . ,(vector 158 158 158))
	("color-248" . ,(vector 168 168 168))
	("color-249" . ,(vector 178 178 178))
	("color-250" . ,(vector 188 188 188))
	("color-251" . ,(vector 198 198 198))
	("color-252" . ,(vector 208 208 208))
	("color-253" . ,(vector 218 218 218))
	("color-254" . ,(vector 228 228 228))
	("color-255" . ,(vector 238 238 238))))

	(setq colortrans--clut
	(cl-loop for (key . value) in colortrans--xtermlut
	collect (cons key (vconcat (mapcar 'colortrans--normalize-rgb value)))))

	(defun colortrans--closest-to-hex-in-alist (rrggbb candidates)
	"Returns the closest color to RRGGBB (in 24-bit hex string format)
	in CANDIDATES.

	CANDIDATES must be an alist with descriptive names as keys, and a vector
	[r g b] as value (r g b in interval [0, 1]).

	Note: RRGGBB must NOT start with a '#'"
	(let* ((hsv_target (colortrans-vec-rgb-to-vec-hsv
	(colortrans-hex-to-vec rrggbb))))
	(--min-by
	(> (colortrans--hsv-distance hsv_target
	(colortrans-vec-rgb-to-vec-hsv (cdr it)))
	(colortrans--hsv-distance hsv_target
	(colortrans-vec-rgb-to-vec-hsv (cdr other))))
	candidates)))

	(defun colortrans-hex-to-xterm (rrggbb)
	"FAILS BECAUSE HUE DOES NOT WRAP AROUND !
	Give color “\"rrggbb\"” string's closest xterm palette counterpart.

	Note: The input string must NOT start with “#”."
	(interactive "sColor to translate: ")
	(colortrans--closest-to-hex-in-alist rrggbb colortrans--clut))

	(defun colortrans-hex-to-name (rrggbb)
	"FAILS BECAUSE HUE DOES NOT WRAP AROUND !
	Give color “\"rrggbb\"” string's closest named color counterpart.

	Note: The input string must NOT start with “#”."
	(interactive "sColor to translate: ")
	(let* ((named_colors (cl-loop for col_name in (defined-colors)
	collect (cons col_name (vconcat (color-name-to-rgb col_name))))))
	(colortrans--closest-to-hex-in-alist rrggbb named_colors)
	))

	(provide 'colortrans)

	;;; colortrans.el ends here