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Diffstat (limited to 'node_modules/chroma-js/src/scale.coffee')
| -rw-r--r-- | node_modules/chroma-js/src/scale.coffee | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/node_modules/chroma-js/src/scale.coffee b/node_modules/chroma-js/src/scale.coffee new file mode 100644 index 0000000000..cef172f543 --- /dev/null +++ b/node_modules/chroma-js/src/scale.coffee @@ -0,0 +1,250 @@ +### + 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 +### + +# minimal multi-purpose interface +chroma.scale = (colors, positions) -> + + # constructor + + _mode = 'rgb' + _nacol = chroma '#ccc' + _spread = 0 + _fixed = false + _domain = [0, 1] + _colors = [] + _out = false + _pos = [] + _min = 0 + _max = 1 + _correctLightness = false + _numClasses = 0 + _colorCache = {} + + # private methods + + setColors = (colors, positions) -> + if not colors? + colors = ['#ddd', '#222'] + if colors? and type(colors) == 'string' and chroma.brewer?[colors]? + colors = chroma.brewer[colors] + if type(colors) == 'array' + # make a copy of the colors + colors = colors.slice(0) + # convert to chroma classes + for c in [0..colors.length-1] + col = colors[c] + colors[c] = chroma(col) if type(col) == "string" + # auto-fill color position + if positions? + _pos = positions + else + _pos = [] + for c in [0..colors.length-1] + _pos.push c/(colors.length-1) + resetCache() + _colors = colors + + setDomain = (domain = []) -> + ### + # use this if you want to display a limited number of data classes + # possible methods are "equalinterval", "quantiles", "custom" + ### + _domain = domain + _min = domain[0] + _max = domain[domain.length-1] + resetCache() + if domain.length == 2 + _numClasses = 0 + else + _numClasses = domain.length-1 + + getClass = (value) -> + if _domain? + n = _domain.length-1 + i = 0 + while i < n and value >= _domain[i] + i++ + return i-1 + return 0 + + tmap = (t) -> t + + classifyValue = (value) -> + val = value + if _domain.length > 2 + n = _domain.length-1 + i = getClass(value) + minc = _domain[0] + (_domain[1]-_domain[0]) * (0 + _spread * 0.5) # center of 1st class + maxc = _domain[n-1] + (_domain[n]-_domain[n-1]) * (1 - _spread * 0.5) # center of last class + val = _min + ((_domain[i] + (_domain[i+1] - _domain[i]) * 0.5 - minc) / (maxc-minc)) * (_max - _min) + val + + getColor = (val, bypassMap=false) -> + if isNaN(val) then return _nacol + if not bypassMap + if _domain.length > 2 + c = getClass val + t = c / (_numClasses-1) + else + t = f0 = if _min != _max then (val - _min) / (_max - _min) else 0 + t = f0 = (val - _min) / (_max - _min) + t = Math.min(1, Math.max(0, t)) + else + t = val + + if not bypassMap + t = tmap t # lightness correction + + k = Math.floor(t * 10000) + + if _colorCache[k] + col = _colorCache[k] + else + if type(_colors) == 'array' + for i in [0.._pos.length-1] + p = _pos[i] + if t <= p + col = _colors[i] + break + if t >= p and i == _pos.length-1 + col = _colors[i] + break + if t > p and t < _pos[i+1] + t = (t-p)/(_pos[i+1]-p) + col = chroma.interpolate _colors[i], _colors[i+1], t, _mode + break + else if type(_colors) == 'function' + col = _colors t + _colorCache[k] = col + col + + resetCache = () -> + _colorCache = {} + + setColors colors, positions + + # public interface + + f = (v) -> + c = getColor v + if _out and c[_out] then c[_out]() else c + + f.domain = (domain, classes, mode='e', key) -> + if not arguments.length + return _domain + if classes? + d = chroma.analyze domain, key + if classes == 0 + domain = [d.min, d.max] + else + domain = chroma.limits d, mode, classes + setDomain domain + f + + f.mode = (_m) -> + if not arguments.length + return _mode + _mode = _m + resetCache() + f + + f.range = (colors, _pos) -> + setColors colors, _pos + f + + f.out = (_o) -> + _out = _o + f + + f.spread = (val) -> + if not arguments.length + return _spread + _spread = val + f + + f.correctLightness = (v) -> + if not arguments.length + return _correctLightness + _correctLightness = v + resetCache() + if _correctLightness + tmap = (t) -> + L0 = getColor(0, true).lab()[0] + L1 = getColor(1, true).lab()[0] + pol = L0 > L1 + L_actual = getColor(t, true).lab()[0] + L_ideal = L0 + (L1 - L0) * t + L_diff = L_actual - L_ideal + t0 = 0 + t1 = 1 + max_iter = 20 + while Math.abs(L_diff) > 1e-2 and max_iter-- > 0 + do () -> + L_diff *= -1 if pol + if L_diff < 0 + t0 = t + t += (t1 - t) * 0.5 + else + t1 = t + t += (t0 - t) * 0.5 + L_actual = getColor(t, true).lab()[0] + L_diff = L_actual - L_ideal + t + else + tmap = (t) -> t + f + + f.colors = (out='hex') -> + # returns all colors based on the defined classes + colors = [] + samples = [] + if _domain.length > 2 + for i in [1..._domain.length] + samples.push (_domain[i-1]+_domain[i])*0.5 + else + samples = _domain + for i in samples + colors.push f(i)[out]() + colors + + f + +# some pre-defined color scales: +chroma.scales ?= {} + +chroma.scales.cool = -> + chroma.scale [chroma.hsl(180,1,.9), chroma.hsl(250,.7,.4)] + +chroma.scales.hot = -> + chroma.scale(['#000','#f00','#ff0','#fff'], [0,.25,.75,1]).mode('rgb') + |