// cpt-city: jmn/jmn-c64 (cpt)
//
// A colourmap with monotonic luminance for simultaneous colour and
// grey-scale publications.
//
// J. McNames, "An effective color scale for simultaneous color and
// gray-scale publications," in IEEE Signal Processing Magazine,
// vol. 23, no. 1, pp. 82-96, Jan. 2006,
//
// author: James McNames
// copyright: Free to use
// year: 2009
// url: https://phillips.shef.ac.uk/pub/cpt-city/jmn
#declare jmn_c64 =
color_map {
  [0.00000 color rgbf <1.0000,1.0000,1.0000,0.0000>]
  [0.01587 color rgbf <0.9882,0.9647,0.9922,0.0000>]
  [0.03175 color rgbf <0.9765,0.9333,0.9882,0.0000>]
  [0.04762 color rgbf <0.9608,0.9059,0.9843,0.0000>]
  [0.06349 color rgbf <0.9412,0.8745,0.9843,0.0000>]
  [0.07936 color rgbf <0.9216,0.8510,0.9843,0.0000>]
  [0.09524 color rgbf <0.8941,0.8235,0.9882,0.0000>]
  [0.11111 color rgbf <0.8667,0.8039,0.9922,0.0000>]
  [0.12698 color rgbf <0.8353,0.7843,0.9922,0.0000>]
  [0.14286 color rgbf <0.8039,0.7647,0.9961,0.0000>]
  [0.15873 color rgbf <0.7686,0.7529,0.9961,0.0000>]
  [0.17460 color rgbf <0.7294,0.7451,0.9961,0.0000>]
  [0.19048 color rgbf <0.6902,0.7373,0.9961,0.0000>]
  [0.20635 color rgbf <0.6471,0.7373,0.9922,0.0000>]
  [0.22222 color rgbf <0.6078,0.7373,0.9843,0.0000>]
  [0.23810 color rgbf <0.5647,0.7412,0.9725,0.0000>]
  [0.25397 color rgbf <0.5216,0.7490,0.9608,0.0000>]
  [0.26984 color rgbf <0.4824,0.7608,0.9412,0.0000>]
  [0.28571 color rgbf <0.4392,0.7765,0.9216,0.0000>]
  [0.30159 color rgbf <0.4039,0.7922,0.8941,0.0000>]
  [0.31746 color rgbf <0.3647,0.8118,0.8667,0.0000>]
  [0.33333 color rgbf <0.3333,0.8314,0.8314,0.0000>]
  [0.34921 color rgbf <0.3020,0.8510,0.7922,0.0000>]
  [0.36508 color rgbf <0.2784,0.8745,0.7490,0.0000>]
  [0.38095 color rgbf <0.2549,0.8941,0.7020,0.0000>]
  [0.39682 color rgbf <0.2392,0.9137,0.6510,0.0000>]
  [0.41270 color rgbf <0.2275,0.9333,0.5961,0.0000>]
  [0.42857 color rgbf <0.2196,0.9529,0.5373,0.0000>]
  [0.44444 color rgbf <0.2157,0.9647,0.4784,0.0000>]
  [0.46032 color rgbf <0.2196,0.9765,0.4157,0.0000>]
  [0.47619 color rgbf <0.2314,0.9804,0.3529,0.0000>]
  [0.49206 color rgbf <0.2471,0.9804,0.2902,0.0000>]
  [0.50794 color rgbf <0.2745,0.9647,0.2314,0.0000>]
  [0.52381 color rgbf <0.3059,0.9333,0.1843,0.0000>]
  [0.53968 color rgbf <0.3373,0.8980,0.1412,0.0000>]
  [0.55556 color rgbf <0.3647,0.8549,0.1059,0.0000>]
  [0.57143 color rgbf <0.3961,0.8078,0.0745,0.0000>]
  [0.58730 color rgbf <0.4196,0.7608,0.0510,0.0000>]
  [0.60318 color rgbf <0.4431,0.7098,0.0314,0.0000>]
  [0.61905 color rgbf <0.4627,0.6549,0.0157,0.0000>]
  [0.63492 color rgbf <0.4784,0.6039,0.0078,0.0000>]
  [0.65079 color rgbf <0.4902,0.5490,0.0000,0.0000>]
  [0.66667 color rgbf <0.4980,0.4980,0.0000,0.0000>]
  [0.68254 color rgbf <0.4980,0.4471,0.0000,0.0000>]
  [0.69841 color rgbf <0.4980,0.3961,0.0039,0.0000>]
  [0.71429 color rgbf <0.4941,0.3451,0.0118,0.0000>]
  [0.73016 color rgbf <0.4824,0.3020,0.0196,0.0000>]
  [0.74603 color rgbf <0.4667,0.2588,0.0314,0.0000>]
  [0.76191 color rgbf <0.4510,0.2196,0.0392,0.0000>]
  [0.77778 color rgbf <0.4275,0.1804,0.0510,0.0000>]
  [0.79365 color rgbf <0.4039,0.1490,0.0627,0.0000>]
  [0.80952 color rgbf <0.3765,0.1176,0.0706,0.0000>]
  [0.82540 color rgbf <0.3451,0.0941,0.0784,0.0000>]
  [0.84127 color rgbf <0.3137,0.0706,0.0863,0.0000>]
  [0.85714 color rgbf <0.2824,0.0510,0.0902,0.0000>]
  [0.87302 color rgbf <0.2471,0.0353,0.0902,0.0000>]
  [0.88889 color rgbf <0.2118,0.0235,0.0902,0.0000>]
  [0.90476 color rgbf <0.1804,0.0157,0.0863,0.0000>]
  [0.92064 color rgbf <0.1451,0.0078,0.0784,0.0000>]
  [0.93651 color rgbf <0.1137,0.0039,0.0706,0.0000>]
  [0.95238 color rgbf <0.0824,0.0000,0.0549,0.0000>]
  [0.96825 color rgbf <0.0510,0.0000,0.0392,0.0000>]
  [0.98413 color rgbf <0.0235,0.0000,0.0196,0.0000>]
  [1.00000 color rgbf <0.0000,0.0000,0.0000,0.0000>]
}