summaryrefslogtreecommitdiff
path: root/chickadee/color.scm
blob: 2d3ac222aac7b5d157d7ca6315dd942bbd236387 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
;;; Chickadee Game Toolkit
;;; Copyright © 2016 David Thompson <davet@gnu.org>
;;;
;;; Chickadee is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License as published
;;; by the Free Software Foundation, either version 3 of the License,
;;; or (at your option) any later version.
;;;
;;; Chickadee is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program.  If not, see
;;; <http://www.gnu.org/licenses/>.

;;; Commentary:
;;
;; Colors!
;;
;;; Code:

(define-module (chickadee color)
  #:use-module (ice-9 match)
  #:use-module (srfi srfi-9)
  #:use-module (srfi srfi-1)
  #:use-module (chickadee math)
  #:export (make-color
            color?
            color-r color-g color-b color-a
            rgba rgb transparency
            color* color+ color- color-inverse color-lerp

            white black red green blue yellow magenta cyan transparent
            tango-light-butter tango-butter tango-dark-butter
            tango-light-orange tango-orange tango-dark-orange
            tango-light-chocolate tango-chocolate tango-dark-chocolate
            tango-light-chameleon tango-chameleon tango-dark-chameleon
            tango-light-sky-blue tango-sky-blue tango-dark-sky-blue
            tango-light-plum tango-plum tango-dark-plum
            tango-light-scarlet-red tango-scarlet-red tango-dark-scarlet-red
            tango-aluminium-1 tango-aluminium-2 tango-aluminium-3
            tango-aluminium-4 tango-aluminium-5 tango-aluminium-6))

(define-record-type <color>
  (%make-color r g b a)
  color?
  (r color-r)
  (g color-g)
  (b color-b)
  (a color-a))

(define (make-color r g b a)
  "Return a newly allocated color with the given RGBA channel values.
Each channel is clamped to the range [0, 1]."
  (%make-color (clamp 0 1 r)
               (clamp 0 1 g)
               (clamp 0 1 b)
               (clamp 0 1 a)))

(define (color-component color-code offset)
  "Return the value of an 8-bit color channel in the range [0,1] for
the integer COLOR-CODE, given an OFFSET in bits."
  (let ((mask (ash #xff offset)))
    (/ (ash (logand mask color-code)
            (- offset))
       255.0)))

(define (rgba color-code)
  "Translate an RGBA format string COLOR-CODE into a color object.
For example: #xffffffff will return a color with RGBA values 1, 1, 1,
1."
  (%make-color (color-component color-code 24)
               (color-component color-code 16)
               (color-component color-code 8)
               (color-component color-code 0)))

(define (rgb color-code)
  "Translate an RGB format string COLOR-CODE into a color object.
For example: #xffffff will return a color with RGBA values 1, 1, 1,
1."
  (%make-color (color-component color-code 16)
               (color-component color-code 8)
               (color-component color-code 0)
               1.0))

(define (transparency alpha)
  "Create a new color that is white with a transparency value of
ALPHA.  ALPHA is clamped to the range [0, 1]."
  (make-color 1 1 1 alpha))

;; (define-method (* (a <<color>>) (b <<color>>))
;;   (make-color (* (color-r a) (color-r b))
;;               (* (color-g a) (color-g b))
;;               (* (color-b a) (color-b b))
;;               (* (color-a a) (color-a b))))

(define color*
  (match-lambda*
   ((($ <color> r1 g1 b1 a1) ($ <color> r2 g2 b2 a2))
    (make-color (* r1 r2)
                (* g1 g2)
                (* b1 b2)
                (* a1 a2)))
   ((($ <color> r g b a) (? number? k))
    (make-color (* r k)
                (* g k)
                (* b k)
                (* a k)))))

(define color+
  (match-lambda*
   ((($ <color> r1 g1 b1 a1) ($ <color> r2 g2 b2 a2))
    (make-color (+ r1 r2)
                (+ g1 g2)
                (+ b1 b2)
                (+ a1 a2)))))

(define color-
  (match-lambda*
   ((($ <color> r1 g1 b1 a1) ($ <color> r2 g2 b2 a2))
    (make-color (- r1 r2)
                (- g1 g2)
                (- b1 b2)
                (- a1 a2)))))

(define color-inverse
  (match-lambda
   (($ <color> r g b a)
    (make-color (- 1 r)
                (- 1 g)
                (- 1 b)
                a)))) ; Do not alter alpha channel.

;;(define color-lerp (make-lerp color+ color*))

;;;
;;; Pre-defined Colors
;;;

;; Basic
(define white (rgb #xffffff))
(define black (rgb #x000000))
(define red (rgb #xff0000))
(define green (rgb #x00ff00))
(define blue (rgb #x0000ff))
(define yellow (rgb #xffff00))
(define magenta (rgb #xff00ff))
(define cyan (rgb #x00ffff))
(define transparent (make-color 0 0 0 0))

;; Tango color pallete
;; http://tango.freedesktop.org
(define tango-light-butter (rgb #xfce94f))
(define tango-butter (rgb #xedd400))
(define tango-dark-butter (rgb #xc4a000))
(define tango-light-orange (rgb #xfcaf3e))
(define tango-orange (rgb #xf57900))
(define tango-dark-orange (rgb #xce5c00))
(define tango-light-chocolate (rgb #xe9b96e))
(define tango-chocolate (rgb #xc17d11))
(define tango-dark-chocolate (rgb #x8f5902))
(define tango-light-chameleon (rgb #x8ae234))
(define tango-chameleon (rgb #x73d216))
(define tango-dark-chameleon (rgb #x4e9a06))
(define tango-light-sky-blue (rgb #x729fcf))
(define tango-sky-blue (rgb #x3465a4))
(define tango-dark-sky-blue (rgb #x204a87))
(define tango-light-plum (rgb #xad7fa8))
(define tango-plum (rgb #x75507b))
(define tango-dark-plum (rgb #x5c3566))
(define tango-light-scarlet-red (rgb #xef2929))
(define tango-scarlet-red (rgb #xcc0000))
(define tango-dark-scarlet-red (rgb #xa40000))
(define tango-aluminium-1 (rgb #xeeeeec))
(define tango-aluminium-2 (rgb #xd3d7cf))
(define tango-aluminium-3 (rgb #xbabdb6))
(define tango-aluminium-4 (rgb #x888a85))
(define tango-aluminium-5 (rgb #x555753))
(define tango-aluminium-6 (rgb #x2e3436))