chroma-js
Version:
JavaScript library for color conversions
334 lines (276 loc) • 9.52 kB
text/coffeescript
chroma.js
Copyright (c) 2011-2013, Gregor Aisch
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* The name Gregor Aisch may not be used to endorse or promote products
derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL GREGOR AISCH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@source: https://github.com/gka/chroma.js
###
class Color
constructor: () ->
me = @
args = []
for arg in arguments
args.push arg if arg?
if args.length == 0
[] = [255,0,255,1,'rgb']
else if type(args[0]) == "array"
if args[0].length == 3
[] = args[0]
a = 1
else if args[0].length == 4
[] = args[0]
else
throw 'unknown input argument'
m = args[1] ? 'rgb'
else if type(args[0]) == "string"
x = args[0]
m = 'hex'
else if type(args[0]) == "object"
[] = args[0]._rgb
m = 'rgb'
else if args.length <= 2 and type(args[0]) == "number"
x = args[0]
m = 'num'
else if args.length >= 3
x = args[0]
y = args[1]
z = args[2]
if args.length == 3
m = 'rgb'
a = 1
else if args.length == 4
if type(args[3]) == "string"
m = args[3]
a = 1
else if type(args[3]) == "number"
m = 'rgb'
a = args[3]
else if args.length == 5
a = args[3]
m = args[4]
a ?= 1
if m == 'rgb'
me._rgb = [x,y,z,a]
else if m == 'gl'
me._rgb = [x*255,y*255,z*255,a]
else if m == 'hsl'
me._rgb = hsl2rgb x,y,z
me._rgb[3] = a
else if m == 'hsv'
me._rgb = hsv2rgb x,y,z
me._rgb[3] = a
else if m == 'hex'
me._rgb = hex2rgb x
else if m == 'lab'
me._rgb = lab2rgb x,y,z
me._rgb[3] = a
else if m == 'lch'
me._rgb = lch2rgb x,y,z
me._rgb[3] = a
else if m == 'hsi'
me._rgb = hsi2rgb x,y,z
me._rgb[3] = a
else if m == 'num'
me._rgb = num2rgb x
me_rgb = clip_rgb me._rgb
rgb: ->
@_rgb.slice 0,3
rgba: ->
@_rgb
hex: (mode='rgb') ->
rgb2hex @_rgb, mode
toString: ->
@name()
hsl: ->
rgb2hsl @_rgb
hsv: ->
rgb2hsv @_rgb
lab: ->
rgb2lab @_rgb
lch: ->
rgb2lch @_rgb
hsi: ->
rgb2hsi @_rgb
gl: ->
[@_rgb[0]/255, @_rgb[1]/255, @_rgb[2]/255, @_rgb[3]]
num: ->
rgb2num @_rgb
luminance: (lum, mode='rgb') ->
return luminance @_rgb if !arguments.length
if lum == 0 then @_rgb = [0,0,0,@_rgb[3]]
if lum == 1 then @_rgb = [255,255,255,@_rgb[3]]
cur_lum = luminance @_rgb
eps = 1e-7
max_iter = 20
test = (l,h) ->
m = l.interpolate(0.5, h, mode)
lm = m.luminance()
if Math.abs(lum - lm) < eps or not max_iter--
return m
if lm > lum
return test(l, m)
return test(m, h)
@_rgb = (if cur_lum > lum then test(new Color('black'), @) else test(@, new Color('white'))).rgba()
@
name: ->
h = @hex()
for k of chroma.colors
if h == chroma.colors[k]
return k
h
alpha: (alpha) ->
if arguments.length
@_rgb[3] = alpha
return @
@_rgb[3]
css: (mode='rgb') ->
me = @
rgb = me._rgb
if mode.length == 3 and rgb[3] < 1
mode += 'a'
if mode == 'rgb'
mode+'('+rgb.slice(0,3).map(round).join(',')+')'
else if mode == 'rgba'
mode+'('+rgb.slice(0,3).map(round).join(',')+','+rgb[3]+')'
else if mode == 'hsl' or mode == 'hsla'
hsl = me.hsl()
rnd = (a) -> round(a*100)/100
hsl[0] = rnd(hsl[0] || 0)
hsl[1] = rnd(hsl[1]*100) + '%'
hsl[2] = rnd(hsl[2]*100) + '%'
if mode.length == 4
hsl[3] = rgb[3]
mode + '(' + hsl.join(',') + ')'
interpolate: (f, col, m) ->
interpolates between colors
f = 0 --> me
f = 1 --> col
me = @
m ?= 'rgb'
col = new Color(col) if type(col) == "string"
if m == 'hsl' or m == 'hsv' or m == 'lch' or m == 'hsi'
if m == 'hsl'
xyz0 = me.hsl()
xyz1 = col.hsl()
else if m == 'hsv'
xyz0 = me.hsv()
xyz1 = col.hsv()
else if m == 'hsi'
xyz0 = me.hsi()
xyz1 = col.hsi()
else if m == 'lch'
xyz0 = me.lch()
xyz1 = col.lch()
if m.substr(0, 1) == 'h'
[] = xyz0
[] = xyz1
else
[] = xyz0
[] = xyz1
if not isNaN(hue0) and not isNaN(hue1)
if hue1 > hue0 and hue1 - hue0 > 180
dh = hue1-(hue0+360)
else if hue1 < hue0 and hue0 - hue1 > 180
dh = hue1+360-hue0
else
dh = hue1 - hue0
hue = hue0+f*dh
else if not isNaN(hue0)
hue = hue0
sat = sat0 if (lbv1 == 1 or lbv1 == 0) and m != 'hsv'
else if not isNaN(hue1)
hue = hue1
sat = sat1 if (lbv0 == 1 or lbv0 == 0) and m != 'hsv'
else
hue = Number.NaN
sat ?= sat0 + f*(sat1 - sat0)
lbv = lbv0 + f*(lbv1-lbv0)
if m.substr(0, 1) == 'h'
res = new Color hue, sat, lbv, m
else
res = new Color lbv, sat, hue, m
else if m == 'rgb'
xyz0 = me._rgb
xyz1 = col._rgb
res = new Color(
xyz0[0]+f*(xyz1[0]-xyz0[0]),
xyz0[1] + f*(xyz1[1]-xyz0[1]),
xyz0[2] + f*(xyz1[2]-xyz0[2]),
m
)
else if m == 'num'
col = new Color(col, m) unless col instanceof Color
xyz0 = me._rgb
xyz1 = col._rgb
res = new Color(
((xyz0[0] + f*(xyz1[0]-xyz0[0])) << 16) +
((xyz0[1] + f*(xyz1[1]-xyz0[1])) << 8) +
((xyz0[2] + f*(xyz1[2]-xyz0[2])) & 0xff),
m
)
else if m == 'lab'
xyz0 = me.lab()
xyz1 = col.lab()
res = new Color(
xyz0[0]+f*(xyz1[0]-xyz0[0]),
xyz0[1] + f*(xyz1[1]-xyz0[1]),
xyz0[2] + f*(xyz1[2]-xyz0[2]),
m
)
else
throw "color mode "+m+" is not supported"
res.alpha me.alpha() + f * (col.alpha() - me.alpha())
res
mix: (f, col, m) ->
@interpolate f, col, m
premultiply: ->
rgb = @rgb()
a = @alpha()
chroma(rgb[0]*a, rgb[1]*a, rgb[2]*a, a)
darken: (amount=20) ->
me = @
lch = me.lch()
lch[0] -= amount
chroma.lch(lch).alpha(me.alpha())
darker: (amount) ->
@darken amount
brighten: (amount=20) ->
@darken -amount
brighter: (amount) ->
@brighten amount
saturate: (amount=20) ->
me = @
lch = me.lch()
lch[1] += amount
chroma.lch(lch).alpha(me.alpha())
desaturate: (amount=20) ->
@saturate -amount
blend: (col, mode) ->
chroma.blend(@, col, mode)
kelvin: () ->
rgb2temp @rgb()