tpapp/cl-colors

Simple color library for Common Lisp

IMPORTANT This library is unsupported.

cl-colors: a simple color library for Common Lisp

This is a very simple color library for Common Lisp, providing

1. Types for representing colors in HSV and RGB spaces.
2. Simple conversion functions between the above types (and also hexadecimal representation for RGB).
3. Some predefined colors (currently X11 color names – of course the library does not depend on X11).

Examples

(let ((color1 (hsv 107 62/100 52/100))          ; greenish
      (color2 (rgb 14/15 26/51 14/15))  ; = violet from X11
      (color3 (as-rgb "ff9e00")))        ; from hexadecimal
  (list                                 ;
   (as-rgb color1)                    ; converting to RGB
   (rgb-combination color1 +blue+ 0.4) ; HSV autoconverted to RGB
   (hsv-combination color2 +blue+ 0.4) ; RGB autoconverted to HSV
   color3))

evaluates to

'(#S(RGB :RED 20059/75000 :GREEN 13/25 :BLUE 247/1250)
  #S(RGB :RED 0.160472 :GREEN 0.312 :BLUE 0.51856) ; observe float contagion
  #S(HSV :HUE 60.0 :SATURATION 0.6722689 :VALUE 0.96000004)
  #S(RGB :RED 1 :GREEN 158/255 :BLUE 0))

Observe the float contagion: cl-colors functions don’t care about the type of the numbers as long as they are a subtype of real and within the right range.

Documentation

This library is so simple that it does not need a lot of documentation — just look at the docsstrings in colors.lisp.

Regeneration of the X11 color names

Normally you should not need to do this, the sources already contain the autogenerated file colornames.lisp. However, if for some reason you need to regenerate this, you can use make. Even though the library itself does not depend on X11, regenerating this file will require the appropriate file in X11.

Bugs and issues

Please report them on Github.

cl-colors's Issues

test.lisp is missing from asdf

As the subject says, asdf is not compiling test.lisp. not sure if that was intentional.

Symbols won't be exported on ABCL

Although this may be a bug of ABCL, some symbols (ex. RGB-RED) won't be exported though they are specified in :export of defpackage.

CL-USER(1): (ql:quickload :cl-colors)
To load "cl-colors":
  Load 1 ASDF system:
    cl-colors
; Loading "cl-colors"
[package cl-colors]
......
(:CL-COLORS)
CL-USER(2): (apropos "rgb-red")
CL-COLORS::RGB-RED (fbound)                 ;; <- not exported

It worked well if I removed the part unexporting symbols.

diff --git a/package.lisp b/package.lisp
index b559140..af16901 100644
--- a/package.lisp
+++ b/package.lisp
@@ -2,6 +2,7 @@

 (in-package #:common-lisp-user)

+#-abcl
 (eval-when (:compile-toplevel :load-toplevel :execute)
   ;; this is needed because the color names in the autogenerated file are
   ;; exported manually and some implementations (eg SBCL) complain about the

No longer exporting color constants?

The older version of cl-colors exported things like cl-colors:+black+ via define-rgb-color. It does not seem like the new version does that any more. This breaks a number of projects which reference cl-colors:+black+ and other stuff. Is this package change intentional or accidental?