ColorTable.cpp

Go to the documentation of this file.

// Gmsh - Copyright (C) 1997-2022 C. Geuzaine, J.-F. Remacle
//
// See the LICENSE.txt file in the Gmsh root directory for license information.
// Please report all issues on https://gitlab.onelab.info/gmsh/gmsh/issues.
//
// Contributor(s):
//   David Colignon
//
 
// These colortable routines were inspired by those provided in Vis5d,
// a program for visualizing five dimensional gridded data sets
// Copyright (C) 1990 - 1995 Bill Hibbard, Brian Paul, Dave Santek,
// and Andre Battaiola.
 
#include <string.h>
#include <algorithm>
#include "GmshMessage.h"
#include "ColorTable.h"
#include "Context.h"
#include "Numeric.h"
 
void ColorTable_InitParam(int number, GmshColorTable *ct)
{
  ct->size = 255;
  for(int i = 0; i < COLORTABLE_NBMAX_PARAM; i++) {
    ct->ipar[i] = 0;
    ct->dpar[i] = 0.;
  }
  ct->ipar[COLORTABLE_MODE] = COLORTABLE_RGB;
  ct->ipar[COLORTABLE_NUMBER] = number;
  ct->dpar[COLORTABLE_ALPHA] = 1.0;
}
 
static double gray(double s) { return s < 0. ? 0. : (s < 1. ? s : 1.); }
 
static double hot_r(double s)
{
  return s < 0. ? 0. : (s < 3. / 8. ? 8. / 3. * s : 1.);
}
 
static double hot_g(double s)
{
  return s < 3. / 8. ? 0. : (s < 6. / 8. ? 8. / 3. * (s - 3. / 8.) : 1.);
}
 
static double hot_b(double s)
{
  return s < 6. / 8. ? 0. : (s < 1. ? 8. / 2. * (s - 6. / 8.) : 1.);
}
 
static double cubic(double a, double b, double c, double d, double x)
{
  return a + b * x + c * x * x + d * x * x * x;
}
 
// New matplotlib colormaps by Nathaniel J. Smith, Stefan van der Walt,
// and (in the case of viridis) Eric Firing.
//
// This file and the colormaps in it are released under the CC0 license /
// public domain dedication. We would appreciate credit if you use or
// redistribute these colormaps, but do not impose any legal restrictions.
//
// To the extent possible under law, the persons who associated CC0 with
// mpl-colormaps have waived all copyright and related or neighboring rights
// to mpl-colormaps.
//
// You should have received a copy of the CC0 legalcode along with this
// work.  If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
 
static double _magma_data[][3] = {
  {0.001462, 0.000466, 0.013866}, {0.002258, 0.001295, 0.018331},
  {0.003279, 0.002305, 0.023708}, {0.004512, 0.003490, 0.029965},
  {0.005950, 0.004843, 0.037130}, {0.007588, 0.006356, 0.044973},
  {0.009426, 0.008022, 0.052844}, {0.011465, 0.009828, 0.060750},
  {0.013708, 0.011771, 0.068667}, {0.016156, 0.013840, 0.076603},
  {0.018815, 0.016026, 0.084584}, {0.021692, 0.018320, 0.092610},
  {0.024792, 0.020715, 0.100676}, {0.028123, 0.023201, 0.108787},
  {0.031696, 0.025765, 0.116965}, {0.035520, 0.028397, 0.125209},
  {0.039608, 0.031090, 0.133515}, {0.043830, 0.033830, 0.141886},
  {0.048062, 0.036607, 0.150327}, {0.052320, 0.039407, 0.158841},
  {0.056615, 0.042160, 0.167446}, {0.060949, 0.044794, 0.176129},
  {0.065330, 0.047318, 0.184892}, {0.069764, 0.049726, 0.193735},
  {0.074257, 0.052017, 0.202660}, {0.078815, 0.054184, 0.211667},
  {0.083446, 0.056225, 0.220755}, {0.088155, 0.058133, 0.229922},
  {0.092949, 0.059904, 0.239164}, {0.097833, 0.061531, 0.248477},
  {0.102815, 0.063010, 0.257854}, {0.107899, 0.064335, 0.267289},
  {0.113094, 0.065492, 0.276784}, {0.118405, 0.066479, 0.286321},
  {0.123833, 0.067295, 0.295879}, {0.129380, 0.067935, 0.305443},
  {0.135053, 0.068391, 0.315000}, {0.140858, 0.068654, 0.324538},
  {0.146785, 0.068738, 0.334011}, {0.152839, 0.068637, 0.343404},
  {0.159018, 0.068354, 0.352688}, {0.165308, 0.067911, 0.361816},
  {0.171713, 0.067305, 0.370771}, {0.178212, 0.066576, 0.379497},
  {0.184801, 0.065732, 0.387973}, {0.191460, 0.064818, 0.396152},
  {0.198177, 0.063862, 0.404009}, {0.204935, 0.062907, 0.411514},
  {0.211718, 0.061992, 0.418647}, {0.218512, 0.061158, 0.425392},
  {0.225302, 0.060445, 0.431742}, {0.232077, 0.059889, 0.437695},
  {0.238826, 0.059517, 0.443256}, {0.245543, 0.059352, 0.448436},
  {0.252220, 0.059415, 0.453248}, {0.258857, 0.059706, 0.457710},
  {0.265447, 0.060237, 0.461840}, {0.271994, 0.060994, 0.465660},
  {0.278493, 0.061978, 0.469190}, {0.284951, 0.063168, 0.472451},
  {0.291366, 0.064553, 0.475462}, {0.297740, 0.066117, 0.478243},
  {0.304081, 0.067835, 0.480812}, {0.310382, 0.069702, 0.483186},
  {0.316654, 0.071690, 0.485380}, {0.322899, 0.073782, 0.487408},
  {0.329114, 0.075972, 0.489287}, {0.335308, 0.078236, 0.491024},
  {0.341482, 0.080564, 0.492631}, {0.347636, 0.082946, 0.494121},
  {0.353773, 0.085373, 0.495501}, {0.359898, 0.087831, 0.496778},
  {0.366012, 0.090314, 0.497960}, {0.372116, 0.092816, 0.499053},
  {0.378211, 0.095332, 0.500067}, {0.384299, 0.097855, 0.501002},
  {0.390384, 0.100379, 0.501864}, {0.396467, 0.102902, 0.502658},
  {0.402548, 0.105420, 0.503386}, {0.408629, 0.107930, 0.504052},
  {0.414709, 0.110431, 0.504662}, {0.420791, 0.112920, 0.505215},
  {0.426877, 0.115395, 0.505714}, {0.432967, 0.117855, 0.506160},
  {0.439062, 0.120298, 0.506555}, {0.445163, 0.122724, 0.506901},
  {0.451271, 0.125132, 0.507198}, {0.457386, 0.127522, 0.507448},
  {0.463508, 0.129893, 0.507652}, {0.469640, 0.132245, 0.507809},
  {0.475780, 0.134577, 0.507921}, {0.481929, 0.136891, 0.507989},
  {0.488088, 0.139186, 0.508011}, {0.494258, 0.141462, 0.507988},
  {0.500438, 0.143719, 0.507920}, {0.506629, 0.145958, 0.507806},
  {0.512831, 0.148179, 0.507648}, {0.519045, 0.150383, 0.507443},
  {0.525270, 0.152569, 0.507192}, {0.531507, 0.154739, 0.506895},
  {0.537755, 0.156894, 0.506551}, {0.544015, 0.159033, 0.506159},
  {0.550287, 0.161158, 0.505719}, {0.556571, 0.163269, 0.505230},
  {0.562866, 0.165368, 0.504692}, {0.569172, 0.167454, 0.504105},
  {0.575490, 0.169530, 0.503466}, {0.581819, 0.171596, 0.502777},
  {0.588158, 0.173652, 0.502035}, {0.594508, 0.175701, 0.501241},
  {0.600868, 0.177743, 0.500394}, {0.607238, 0.179779, 0.499492},
  {0.613617, 0.181811, 0.498536}, {0.620005, 0.183840, 0.497524},
  {0.626401, 0.185867, 0.496456}, {0.632805, 0.187893, 0.495332},
  {0.639216, 0.189921, 0.494150}, {0.645633, 0.191952, 0.492910},
  {0.652056, 0.193986, 0.491611}, {0.658483, 0.196027, 0.490253},
  {0.664915, 0.198075, 0.488836}, {0.671349, 0.200133, 0.487358},
  {0.677786, 0.202203, 0.485819}, {0.684224, 0.204286, 0.484219},
  {0.690661, 0.206384, 0.482558}, {0.697098, 0.208501, 0.480835},
  {0.703532, 0.210638, 0.479049}, {0.709962, 0.212797, 0.477201},
  {0.716387, 0.214982, 0.475290}, {0.722805, 0.217194, 0.473316},
  {0.729216, 0.219437, 0.471279}, {0.735616, 0.221713, 0.469180},
  {0.742004, 0.224025, 0.467018}, {0.748378, 0.226377, 0.464794},
  {0.754737, 0.228772, 0.462509}, {0.761077, 0.231214, 0.460162},
  {0.767398, 0.233705, 0.457755}, {0.773695, 0.236249, 0.455289},
  {0.779968, 0.238851, 0.452765}, {0.786212, 0.241514, 0.450184},
  {0.792427, 0.244242, 0.447543}, {0.798608, 0.247040, 0.444848},
  {0.804752, 0.249911, 0.442102}, {0.810855, 0.252861, 0.439305},
  {0.816914, 0.255895, 0.436461}, {0.822926, 0.259016, 0.433573},
  {0.828886, 0.262229, 0.430644}, {0.834791, 0.265540, 0.427671},
  {0.840636, 0.268953, 0.424666}, {0.846416, 0.272473, 0.421631},
  {0.852126, 0.276106, 0.418573}, {0.857763, 0.279857, 0.415496},
  {0.863320, 0.283729, 0.412403}, {0.868793, 0.287728, 0.409303},
  {0.874176, 0.291859, 0.406205}, {0.879464, 0.296125, 0.403118},
  {0.884651, 0.300530, 0.400047}, {0.889731, 0.305079, 0.397002},
  {0.894700, 0.309773, 0.393995}, {0.899552, 0.314616, 0.391037},
  {0.904281, 0.319610, 0.388137}, {0.908884, 0.324755, 0.385308},
  {0.913354, 0.330052, 0.382563}, {0.917689, 0.335500, 0.379915},
  {0.921884, 0.341098, 0.377376}, {0.925937, 0.346844, 0.374959},
  {0.929845, 0.352734, 0.372677}, {0.933606, 0.358764, 0.370541},
  {0.937221, 0.364929, 0.368567}, {0.940687, 0.371224, 0.366762},
  {0.944006, 0.377643, 0.365136}, {0.947180, 0.384178, 0.363701},
  {0.950210, 0.390820, 0.362468}, {0.953099, 0.397563, 0.361438},
  {0.955849, 0.404400, 0.360619}, {0.958464, 0.411324, 0.360014},
  {0.960949, 0.418323, 0.359630}, {0.963310, 0.425390, 0.359469},
  {0.965549, 0.432519, 0.359529}, {0.967671, 0.439703, 0.359810},
  {0.969680, 0.446936, 0.360311}, {0.971582, 0.454210, 0.361030},
  {0.973381, 0.461520, 0.361965}, {0.975082, 0.468861, 0.363111},
  {0.976690, 0.476226, 0.364466}, {0.978210, 0.483612, 0.366025},
  {0.979645, 0.491014, 0.367783}, {0.981000, 0.498428, 0.369734},
  {0.982279, 0.505851, 0.371874}, {0.983485, 0.513280, 0.374198},
  {0.984622, 0.520713, 0.376698}, {0.985693, 0.528148, 0.379371},
  {0.986700, 0.535582, 0.382210}, {0.987646, 0.543015, 0.385210},
  {0.988533, 0.550446, 0.388365}, {0.989363, 0.557873, 0.391671},
  {0.990138, 0.565296, 0.395122}, {0.990871, 0.572706, 0.398714},
  {0.991558, 0.580107, 0.402441}, {0.992196, 0.587502, 0.406299},
  {0.992785, 0.594891, 0.410283}, {0.993326, 0.602275, 0.414390},
  {0.993834, 0.609644, 0.418613}, {0.994309, 0.616999, 0.422950},
  {0.994738, 0.624350, 0.427397}, {0.995122, 0.631696, 0.431951},
  {0.995480, 0.639027, 0.436607}, {0.995810, 0.646344, 0.441361},
  {0.996096, 0.653659, 0.446213}, {0.996341, 0.660969, 0.451160},
  {0.996580, 0.668256, 0.456192}, {0.996775, 0.675541, 0.461314},
  {0.996925, 0.682828, 0.466526}, {0.997077, 0.690088, 0.471811},
  {0.997186, 0.697349, 0.477182}, {0.997254, 0.704611, 0.482635},
  {0.997325, 0.711848, 0.488154}, {0.997351, 0.719089, 0.493755},
  {0.997351, 0.726324, 0.499428}, {0.997341, 0.733545, 0.505167},
  {0.997285, 0.740772, 0.510983}, {0.997228, 0.747981, 0.516859},
  {0.997138, 0.755190, 0.522806}, {0.997019, 0.762398, 0.528821},
  {0.996898, 0.769591, 0.534892}, {0.996727, 0.776795, 0.541039},
  {0.996571, 0.783977, 0.547233}, {0.996369, 0.791167, 0.553499},
  {0.996162, 0.798348, 0.559820}, {0.995932, 0.805527, 0.566202},
  {0.995680, 0.812706, 0.572645}, {0.995424, 0.819875, 0.579140},
  {0.995131, 0.827052, 0.585701}, {0.994851, 0.834213, 0.592307},
  {0.994524, 0.841387, 0.598983}, {0.994222, 0.848540, 0.605696},
  {0.993866, 0.855711, 0.612482}, {0.993545, 0.862859, 0.619299},
  {0.993170, 0.870024, 0.626189}, {0.992831, 0.877168, 0.633109},
  {0.992440, 0.884330, 0.640099}, {0.992089, 0.891470, 0.647116},
  {0.991688, 0.898627, 0.654202}, {0.991332, 0.905763, 0.661309},
  {0.990930, 0.912915, 0.668481}, {0.990570, 0.920049, 0.675675},
  {0.990175, 0.927196, 0.682926}, {0.989815, 0.934329, 0.690198},
  {0.989434, 0.941470, 0.697519}, {0.989077, 0.948604, 0.704863},
  {0.988717, 0.955742, 0.712242}, {0.988367, 0.962878, 0.719649},
  {0.988033, 0.970012, 0.727077}, {0.987691, 0.977154, 0.734536},
  {0.987387, 0.984288, 0.742002}, {0.987053, 0.991438, 0.749504}};
 
static double _inferno_data[][3] = {
  {0.001462, 0.000466, 0.013866}, {0.002267, 0.001270, 0.018570},
  {0.003299, 0.002249, 0.024239}, {0.004547, 0.003392, 0.030909},
  {0.006006, 0.004692, 0.038558}, {0.007676, 0.006136, 0.046836},
  {0.009561, 0.007713, 0.055143}, {0.011663, 0.009417, 0.063460},
  {0.013995, 0.011225, 0.071862}, {0.016561, 0.013136, 0.080282},
  {0.019373, 0.015133, 0.088767}, {0.022447, 0.017199, 0.097327},
  {0.025793, 0.019331, 0.105930}, {0.029432, 0.021503, 0.114621},
  {0.033385, 0.023702, 0.123397}, {0.037668, 0.025921, 0.132232},
  {0.042253, 0.028139, 0.141141}, {0.046915, 0.030324, 0.150164},
  {0.051644, 0.032474, 0.159254}, {0.056449, 0.034569, 0.168414},
  {0.061340, 0.036590, 0.177642}, {0.066331, 0.038504, 0.186962},
  {0.071429, 0.040294, 0.196354}, {0.076637, 0.041905, 0.205799},
  {0.081962, 0.043328, 0.215289}, {0.087411, 0.044556, 0.224813},
  {0.092990, 0.045583, 0.234358}, {0.098702, 0.046402, 0.243904},
  {0.104551, 0.047008, 0.253430}, {0.110536, 0.047399, 0.262912},
  {0.116656, 0.047574, 0.272321}, {0.122908, 0.047536, 0.281624},
  {0.129285, 0.047293, 0.290788}, {0.135778, 0.046856, 0.299776},
  {0.142378, 0.046242, 0.308553}, {0.149073, 0.045468, 0.317085},
  {0.155850, 0.044559, 0.325338}, {0.162689, 0.043554, 0.333277},
  {0.169575, 0.042489, 0.340874}, {0.176493, 0.041402, 0.348111},
  {0.183429, 0.040329, 0.354971}, {0.190367, 0.039309, 0.361447},
  {0.197297, 0.038400, 0.367535}, {0.204209, 0.037632, 0.373238},
  {0.211095, 0.037030, 0.378563}, {0.217949, 0.036615, 0.383522},
  {0.224763, 0.036405, 0.388129}, {0.231538, 0.036405, 0.392400},
  {0.238273, 0.036621, 0.396353}, {0.244967, 0.037055, 0.400007},
  {0.251620, 0.037705, 0.403378}, {0.258234, 0.038571, 0.406485},
  {0.264810, 0.039647, 0.409345}, {0.271347, 0.040922, 0.411976},
  {0.277850, 0.042353, 0.414392}, {0.284321, 0.043933, 0.416608},
  {0.290763, 0.045644, 0.418637}, {0.297178, 0.047470, 0.420491},
  {0.303568, 0.049396, 0.422182}, {0.309935, 0.051407, 0.423721},
  {0.316282, 0.053490, 0.425116}, {0.322610, 0.055634, 0.426377},
  {0.328921, 0.057827, 0.427511}, {0.335217, 0.060060, 0.428524},
  {0.341500, 0.062325, 0.429425}, {0.347771, 0.064616, 0.430217},
  {0.354032, 0.066925, 0.430906}, {0.360284, 0.069247, 0.431497},
  {0.366529, 0.071579, 0.431994}, {0.372768, 0.073915, 0.432400},
  {0.379001, 0.076253, 0.432719}, {0.385228, 0.078591, 0.432955},
  {0.391453, 0.080927, 0.433109}, {0.397674, 0.083257, 0.433183},
  {0.403894, 0.085580, 0.433179}, {0.410113, 0.087896, 0.433098},
  {0.416331, 0.090203, 0.432943}, {0.422549, 0.092501, 0.432714},
  {0.428768, 0.094790, 0.432412}, {0.434987, 0.097069, 0.432039},
  {0.441207, 0.099338, 0.431594}, {0.447428, 0.101597, 0.431080},
  {0.453651, 0.103848, 0.430498}, {0.459875, 0.106089, 0.429846},
  {0.466100, 0.108322, 0.429125}, {0.472328, 0.110547, 0.428334},
  {0.478558, 0.112764, 0.427475}, {0.484789, 0.114974, 0.426548},
  {0.491022, 0.117179, 0.425552}, {0.497257, 0.119379, 0.424488},
  {0.503493, 0.121575, 0.423356}, {0.509730, 0.123769, 0.422156},
  {0.515967, 0.125960, 0.420887}, {0.522206, 0.128150, 0.419549},
  {0.528444, 0.130341, 0.418142}, {0.534683, 0.132534, 0.416667},
  {0.540920, 0.134729, 0.415123}, {0.547157, 0.136929, 0.413511},
  {0.553392, 0.139134, 0.411829}, {0.559624, 0.141346, 0.410078},
  {0.565854, 0.143567, 0.408258}, {0.572081, 0.145797, 0.406369},
  {0.578304, 0.148039, 0.404411}, {0.584521, 0.150294, 0.402385},
  {0.590734, 0.152563, 0.400290}, {0.596940, 0.154848, 0.398125},
  {0.603139, 0.157151, 0.395891}, {0.609330, 0.159474, 0.393589},
  {0.615513, 0.161817, 0.391219}, {0.621685, 0.164184, 0.388781},
  {0.627847, 0.166575, 0.386276}, {0.633998, 0.168992, 0.383704},
  {0.640135, 0.171438, 0.381065}, {0.646260, 0.173914, 0.378359},
  {0.652369, 0.176421, 0.375586}, {0.658463, 0.178962, 0.372748},
  {0.664540, 0.181539, 0.369846}, {0.670599, 0.184153, 0.366879},
  {0.676638, 0.186807, 0.363849}, {0.682656, 0.189501, 0.360757},
  {0.688653, 0.192239, 0.357603}, {0.694627, 0.195021, 0.354388},
  {0.700576, 0.197851, 0.351113}, {0.706500, 0.200728, 0.347777},
  {0.712396, 0.203656, 0.344383}, {0.718264, 0.206636, 0.340931},
  {0.724103, 0.209670, 0.337424}, {0.729909, 0.212759, 0.333861},
  {0.735683, 0.215906, 0.330245}, {0.741423, 0.219112, 0.326576},
  {0.747127, 0.222378, 0.322856}, {0.752794, 0.225706, 0.319085},
  {0.758422, 0.229097, 0.315266}, {0.764010, 0.232554, 0.311399},
  {0.769556, 0.236077, 0.307485}, {0.775059, 0.239667, 0.303526},
  {0.780517, 0.243327, 0.299523}, {0.785929, 0.247056, 0.295477},
  {0.791293, 0.250856, 0.291390}, {0.796607, 0.254728, 0.287264},
  {0.801871, 0.258674, 0.283099}, {0.807082, 0.262692, 0.278898},
  {0.812239, 0.266786, 0.274661}, {0.817341, 0.270954, 0.270390},
  {0.822386, 0.275197, 0.266085}, {0.827372, 0.279517, 0.261750},
  {0.832299, 0.283913, 0.257383}, {0.837165, 0.288385, 0.252988},
  {0.841969, 0.292933, 0.248564}, {0.846709, 0.297559, 0.244113},
  {0.851384, 0.302260, 0.239636}, {0.855992, 0.307038, 0.235133},
  {0.860533, 0.311892, 0.230606}, {0.865006, 0.316822, 0.226055},
  {0.869409, 0.321827, 0.221482}, {0.873741, 0.326906, 0.216886},
  {0.878001, 0.332060, 0.212268}, {0.882188, 0.337287, 0.207628},
  {0.886302, 0.342586, 0.202968}, {0.890341, 0.347957, 0.198286},
  {0.894305, 0.353399, 0.193584}, {0.898192, 0.358911, 0.188860},
  {0.902003, 0.364492, 0.184116}, {0.905735, 0.370140, 0.179350},
  {0.909390, 0.375856, 0.174563}, {0.912966, 0.381636, 0.169755},
  {0.916462, 0.387481, 0.164924}, {0.919879, 0.393389, 0.160070},
  {0.923215, 0.399359, 0.155193}, {0.926470, 0.405389, 0.150292},
  {0.929644, 0.411479, 0.145367}, {0.932737, 0.417627, 0.140417},
  {0.935747, 0.423831, 0.135440}, {0.938675, 0.430091, 0.130438},
  {0.941521, 0.436405, 0.125409}, {0.944285, 0.442772, 0.120354},
  {0.946965, 0.449191, 0.115272}, {0.949562, 0.455660, 0.110164},
  {0.952075, 0.462178, 0.105031}, {0.954506, 0.468744, 0.099874},
  {0.956852, 0.475356, 0.094695}, {0.959114, 0.482014, 0.089499},
  {0.961293, 0.488716, 0.084289}, {0.963387, 0.495462, 0.079073},
  {0.965397, 0.502249, 0.073859}, {0.967322, 0.509078, 0.068659},
  {0.969163, 0.515946, 0.063488}, {0.970919, 0.522853, 0.058367},
  {0.972590, 0.529798, 0.053324}, {0.974176, 0.536780, 0.048392},
  {0.975677, 0.543798, 0.043618}, {0.977092, 0.550850, 0.039050},
  {0.978422, 0.557937, 0.034931}, {0.979666, 0.565057, 0.031409},
  {0.980824, 0.572209, 0.028508}, {0.981895, 0.579392, 0.026250},
  {0.982881, 0.586606, 0.024661}, {0.983779, 0.593849, 0.023770},
  {0.984591, 0.601122, 0.023606}, {0.985315, 0.608422, 0.024202},
  {0.985952, 0.615750, 0.025592}, {0.986502, 0.623105, 0.027814},
  {0.986964, 0.630485, 0.030908}, {0.987337, 0.637890, 0.034916},
  {0.987622, 0.645320, 0.039886}, {0.987819, 0.652773, 0.045581},
  {0.987926, 0.660250, 0.051750}, {0.987945, 0.667748, 0.058329},
  {0.987874, 0.675267, 0.065257}, {0.987714, 0.682807, 0.072489},
  {0.987464, 0.690366, 0.079990}, {0.987124, 0.697944, 0.087731},
  {0.986694, 0.705540, 0.095694}, {0.986175, 0.713153, 0.103863},
  {0.985566, 0.720782, 0.112229}, {0.984865, 0.728427, 0.120785},
  {0.984075, 0.736087, 0.129527}, {0.983196, 0.743758, 0.138453},
  {0.982228, 0.751442, 0.147565}, {0.981173, 0.759135, 0.156863},
  {0.980032, 0.766837, 0.166353}, {0.978806, 0.774545, 0.176037},
  {0.977497, 0.782258, 0.185923}, {0.976108, 0.789974, 0.196018},
  {0.974638, 0.797692, 0.206332}, {0.973088, 0.805409, 0.216877},
  {0.971468, 0.813122, 0.227658}, {0.969783, 0.820825, 0.238686},
  {0.968041, 0.828515, 0.249972}, {0.966243, 0.836191, 0.261534},
  {0.964394, 0.843848, 0.273391}, {0.962517, 0.851476, 0.285546},
  {0.960626, 0.859069, 0.298010}, {0.958720, 0.866624, 0.310820},
  {0.956834, 0.874129, 0.323974}, {0.954997, 0.881569, 0.337475},
  {0.953215, 0.888942, 0.351369}, {0.951546, 0.896226, 0.365627},
  {0.950018, 0.903409, 0.380271}, {0.948683, 0.910473, 0.395289},
  {0.947594, 0.917399, 0.410665}, {0.946809, 0.924168, 0.426373},
  {0.946392, 0.930761, 0.442367}, {0.946403, 0.937159, 0.458592},
  {0.946903, 0.943348, 0.474970}, {0.947937, 0.949318, 0.491426},
  {0.949545, 0.955063, 0.507860}, {0.951740, 0.960587, 0.524203},
  {0.954529, 0.965896, 0.540361}, {0.957896, 0.971003, 0.556275},
  {0.961812, 0.975924, 0.571925}, {0.966249, 0.980678, 0.587206},
  {0.971162, 0.985282, 0.602154}, {0.976511, 0.989753, 0.616760},
  {0.982257, 0.994109, 0.631017}, {0.988362, 0.998364, 0.644924}};
 
static double _plasma_data[][3] = {
  {0.050383, 0.029803, 0.527975}, {0.063536, 0.028426, 0.533124},
  {0.075353, 0.027206, 0.538007}, {0.086222, 0.026125, 0.542658},
  {0.096379, 0.025165, 0.547103}, {0.105980, 0.024309, 0.551368},
  {0.115124, 0.023556, 0.555468}, {0.123903, 0.022878, 0.559423},
  {0.132381, 0.022258, 0.563250}, {0.140603, 0.021687, 0.566959},
  {0.148607, 0.021154, 0.570562}, {0.156421, 0.020651, 0.574065},
  {0.164070, 0.020171, 0.577478}, {0.171574, 0.019706, 0.580806},
  {0.178950, 0.019252, 0.584054}, {0.186213, 0.018803, 0.587228},
  {0.193374, 0.018354, 0.590330}, {0.200445, 0.017902, 0.593364},
  {0.207435, 0.017442, 0.596333}, {0.214350, 0.016973, 0.599239},
  {0.221197, 0.016497, 0.602083}, {0.227983, 0.016007, 0.604867},
  {0.234715, 0.015502, 0.607592}, {0.241396, 0.014979, 0.610259},
  {0.248032, 0.014439, 0.612868}, {0.254627, 0.013882, 0.615419},
  {0.261183, 0.013308, 0.617911}, {0.267703, 0.012716, 0.620346},
  {0.274191, 0.012109, 0.622722}, {0.280648, 0.011488, 0.625038},
  {0.287076, 0.010855, 0.627295}, {0.293478, 0.010213, 0.629490},
  {0.299855, 0.009561, 0.631624}, {0.306210, 0.008902, 0.633694},
  {0.312543, 0.008239, 0.635700}, {0.318856, 0.007576, 0.637640},
  {0.325150, 0.006915, 0.639512}, {0.331426, 0.006261, 0.641316},
  {0.337683, 0.005618, 0.643049}, {0.343925, 0.004991, 0.644710},
  {0.350150, 0.004382, 0.646298}, {0.356359, 0.003798, 0.647810},
  {0.362553, 0.003243, 0.649245}, {0.368733, 0.002724, 0.650601},
  {0.374897, 0.002245, 0.651876}, {0.381047, 0.001814, 0.653068},
  {0.387183, 0.001434, 0.654177}, {0.393304, 0.001114, 0.655199},
  {0.399411, 0.000859, 0.656133}, {0.405503, 0.000678, 0.656977},
  {0.411580, 0.000577, 0.657730}, {0.417642, 0.000564, 0.658390},
  {0.423689, 0.000646, 0.658956}, {0.429719, 0.000831, 0.659425},
  {0.435734, 0.001127, 0.659797}, {0.441732, 0.001540, 0.660069},
  {0.447714, 0.002080, 0.660240}, {0.453677, 0.002755, 0.660310},
  {0.459623, 0.003574, 0.660277}, {0.465550, 0.004545, 0.660139},
  {0.471457, 0.005678, 0.659897}, {0.477344, 0.006980, 0.659549},
  {0.483210, 0.008460, 0.659095}, {0.489055, 0.010127, 0.658534},
  {0.494877, 0.011990, 0.657865}, {0.500678, 0.014055, 0.657088},
  {0.506454, 0.016333, 0.656202}, {0.512206, 0.018833, 0.655209},
  {0.517933, 0.021563, 0.654109}, {0.523633, 0.024532, 0.652901},
  {0.529306, 0.027747, 0.651586}, {0.534952, 0.031217, 0.650165},
  {0.540570, 0.034950, 0.648640}, {0.546157, 0.038954, 0.647010},
  {0.551715, 0.043136, 0.645277}, {0.557243, 0.047331, 0.643443},
  {0.562738, 0.051545, 0.641509}, {0.568201, 0.055778, 0.639477},
  {0.573632, 0.060028, 0.637349}, {0.579029, 0.064296, 0.635126},
  {0.584391, 0.068579, 0.632812}, {0.589719, 0.072878, 0.630408},
  {0.595011, 0.077190, 0.627917}, {0.600266, 0.081516, 0.625342},
  {0.605485, 0.085854, 0.622686}, {0.610667, 0.090204, 0.619951},
  {0.615812, 0.094564, 0.617140}, {0.620919, 0.098934, 0.614257},
  {0.625987, 0.103312, 0.611305}, {0.631017, 0.107699, 0.608287},
  {0.636008, 0.112092, 0.605205}, {0.640959, 0.116492, 0.602065},
  {0.645872, 0.120898, 0.598867}, {0.650746, 0.125309, 0.595617},
  {0.655580, 0.129725, 0.592317}, {0.660374, 0.134144, 0.588971},
  {0.665129, 0.138566, 0.585582}, {0.669845, 0.142992, 0.582154},
  {0.674522, 0.147419, 0.578688}, {0.679160, 0.151848, 0.575189},
  {0.683758, 0.156278, 0.571660}, {0.688318, 0.160709, 0.568103},
  {0.692840, 0.165141, 0.564522}, {0.697324, 0.169573, 0.560919},
  {0.701769, 0.174005, 0.557296}, {0.706178, 0.178437, 0.553657},
  {0.710549, 0.182868, 0.550004}, {0.714883, 0.187299, 0.546338},
  {0.719181, 0.191729, 0.542663}, {0.723444, 0.196158, 0.538981},
  {0.727670, 0.200586, 0.535293}, {0.731862, 0.205013, 0.531601},
  {0.736019, 0.209439, 0.527908}, {0.740143, 0.213864, 0.524216},
  {0.744232, 0.218288, 0.520524}, {0.748289, 0.222711, 0.516834},
  {0.752312, 0.227133, 0.513149}, {0.756304, 0.231555, 0.509468},
  {0.760264, 0.235976, 0.505794}, {0.764193, 0.240396, 0.502126},
  {0.768090, 0.244817, 0.498465}, {0.771958, 0.249237, 0.494813},
  {0.775796, 0.253658, 0.491171}, {0.779604, 0.258078, 0.487539},
  {0.783383, 0.262500, 0.483918}, {0.787133, 0.266922, 0.480307},
  {0.790855, 0.271345, 0.476706}, {0.794549, 0.275770, 0.473117},
  {0.798216, 0.280197, 0.469538}, {0.801855, 0.284626, 0.465971},
  {0.805467, 0.289057, 0.462415}, {0.809052, 0.293491, 0.458870},
  {0.812612, 0.297928, 0.455338}, {0.816144, 0.302368, 0.451816},
  {0.819651, 0.306812, 0.448306}, {0.823132, 0.311261, 0.444806},
  {0.826588, 0.315714, 0.441316}, {0.830018, 0.320172, 0.437836},
  {0.833422, 0.324635, 0.434366}, {0.836801, 0.329105, 0.430905},
  {0.840155, 0.333580, 0.427455}, {0.843484, 0.338062, 0.424013},
  {0.846788, 0.342551, 0.420579}, {0.850066, 0.347048, 0.417153},
  {0.853319, 0.351553, 0.413734}, {0.856547, 0.356066, 0.410322},
  {0.859750, 0.360588, 0.406917}, {0.862927, 0.365119, 0.403519},
  {0.866078, 0.369660, 0.400126}, {0.869203, 0.374212, 0.396738},
  {0.872303, 0.378774, 0.393355}, {0.875376, 0.383347, 0.389976},
  {0.878423, 0.387932, 0.386600}, {0.881443, 0.392529, 0.383229},
  {0.884436, 0.397139, 0.379860}, {0.887402, 0.401762, 0.376494},
  {0.890340, 0.406398, 0.373130}, {0.893250, 0.411048, 0.369768},
  {0.896131, 0.415712, 0.366407}, {0.898984, 0.420392, 0.363047},
  {0.901807, 0.425087, 0.359688}, {0.904601, 0.429797, 0.356329},
  {0.907365, 0.434524, 0.352970}, {0.910098, 0.439268, 0.349610},
  {0.912800, 0.444029, 0.346251}, {0.915471, 0.448807, 0.342890},
  {0.918109, 0.453603, 0.339529}, {0.920714, 0.458417, 0.336166},
  {0.923287, 0.463251, 0.332801}, {0.925825, 0.468103, 0.329435},
  {0.928329, 0.472975, 0.326067}, {0.930798, 0.477867, 0.322697},
  {0.933232, 0.482780, 0.319325}, {0.935630, 0.487712, 0.315952},
  {0.937990, 0.492667, 0.312575}, {0.940313, 0.497642, 0.309197},
  {0.942598, 0.502639, 0.305816}, {0.944844, 0.507658, 0.302433},
  {0.947051, 0.512699, 0.299049}, {0.949217, 0.517763, 0.295662},
  {0.951344, 0.522850, 0.292275}, {0.953428, 0.527960, 0.288883},
  {0.955470, 0.533093, 0.285490}, {0.957469, 0.538250, 0.282096},
  {0.959424, 0.543431, 0.278701}, {0.961336, 0.548636, 0.275305},
  {0.963203, 0.553865, 0.271909}, {0.965024, 0.559118, 0.268513},
  {0.966798, 0.564396, 0.265118}, {0.968526, 0.569700, 0.261721},
  {0.970205, 0.575028, 0.258325}, {0.971835, 0.580382, 0.254931},
  {0.973416, 0.585761, 0.251540}, {0.974947, 0.591165, 0.248151},
  {0.976428, 0.596595, 0.244767}, {0.977856, 0.602051, 0.241387},
  {0.979233, 0.607532, 0.238013}, {0.980556, 0.613039, 0.234646},
  {0.981826, 0.618572, 0.231287}, {0.983041, 0.624131, 0.227937},
  {0.984199, 0.629718, 0.224595}, {0.985301, 0.635330, 0.221265},
  {0.986345, 0.640969, 0.217948}, {0.987332, 0.646633, 0.214648},
  {0.988260, 0.652325, 0.211364}, {0.989128, 0.658043, 0.208100},
  {0.989935, 0.663787, 0.204859}, {0.990681, 0.669558, 0.201642},
  {0.991365, 0.675355, 0.198453}, {0.991985, 0.681179, 0.195295},
  {0.992541, 0.687030, 0.192170}, {0.993032, 0.692907, 0.189084},
  {0.993456, 0.698810, 0.186041}, {0.993814, 0.704741, 0.183043},
  {0.994103, 0.710698, 0.180097}, {0.994324, 0.716681, 0.177208},
  {0.994474, 0.722691, 0.174381}, {0.994553, 0.728728, 0.171622},
  {0.994561, 0.734791, 0.168938}, {0.994495, 0.740880, 0.166335},
  {0.994355, 0.746995, 0.163821}, {0.994141, 0.753137, 0.161404},
  {0.993851, 0.759304, 0.159092}, {0.993482, 0.765499, 0.156891},
  {0.993033, 0.771720, 0.154808}, {0.992505, 0.777967, 0.152855},
  {0.991897, 0.784239, 0.151042}, {0.991209, 0.790537, 0.149377},
  {0.990439, 0.796859, 0.147870}, {0.989587, 0.803205, 0.146529},
  {0.988648, 0.809579, 0.145357}, {0.987621, 0.815978, 0.144363},
  {0.986509, 0.822401, 0.143557}, {0.985314, 0.828846, 0.142945},
  {0.984031, 0.835315, 0.142528}, {0.982653, 0.841812, 0.142303},
  {0.981190, 0.848329, 0.142279}, {0.979644, 0.854866, 0.142453},
  {0.977995, 0.861432, 0.142808}, {0.976265, 0.868016, 0.143351},
  {0.974443, 0.874622, 0.144061}, {0.972530, 0.881250, 0.144923},
  {0.970533, 0.887896, 0.145919}, {0.968443, 0.894564, 0.147014},
  {0.966271, 0.901249, 0.148180}, {0.964021, 0.907950, 0.149370},
  {0.961681, 0.914672, 0.150520}, {0.959276, 0.921407, 0.151566},
  {0.956808, 0.928152, 0.152409}, {0.954287, 0.934908, 0.152921},
  {0.951726, 0.941671, 0.152925}, {0.949151, 0.948435, 0.152178},
  {0.946602, 0.955190, 0.150328}, {0.944152, 0.961916, 0.146861},
  {0.941896, 0.968590, 0.140956}, {0.940015, 0.975158, 0.131326}};
 
static double _viridis_data[][3] = {
  {0.267004, 0.004874, 0.329415}, {0.268510, 0.009605, 0.335427},
  {0.269944, 0.014625, 0.341379}, {0.271305, 0.019942, 0.347269},
  {0.272594, 0.025563, 0.353093}, {0.273809, 0.031497, 0.358853},
  {0.274952, 0.037752, 0.364543}, {0.276022, 0.044167, 0.370164},
  {0.277018, 0.050344, 0.375715}, {0.277941, 0.056324, 0.381191},
  {0.278791, 0.062145, 0.386592}, {0.279566, 0.067836, 0.391917},
  {0.280267, 0.073417, 0.397163}, {0.280894, 0.078907, 0.402329},
  {0.281446, 0.084320, 0.407414}, {0.281924, 0.089666, 0.412415},
  {0.282327, 0.094955, 0.417331}, {0.282656, 0.100196, 0.422160},
  {0.282910, 0.105393, 0.426902}, {0.283091, 0.110553, 0.431554},
  {0.283197, 0.115680, 0.436115}, {0.283229, 0.120777, 0.440584},
  {0.283187, 0.125848, 0.444960}, {0.283072, 0.130895, 0.449241},
  {0.282884, 0.135920, 0.453427}, {0.282623, 0.140926, 0.457517},
  {0.282290, 0.145912, 0.461510}, {0.281887, 0.150881, 0.465405},
  {0.281412, 0.155834, 0.469201}, {0.280868, 0.160771, 0.472899},
  {0.280255, 0.165693, 0.476498}, {0.279574, 0.170599, 0.479997},
  {0.278826, 0.175490, 0.483397}, {0.278012, 0.180367, 0.486697},
  {0.277134, 0.185228, 0.489898}, {0.276194, 0.190074, 0.493001},
  {0.275191, 0.194905, 0.496005}, {0.274128, 0.199721, 0.498911},
  {0.273006, 0.204520, 0.501721}, {0.271828, 0.209303, 0.504434},
  {0.270595, 0.214069, 0.507052}, {0.269308, 0.218818, 0.509577},
  {0.267968, 0.223549, 0.512008}, {0.266580, 0.228262, 0.514349},
  {0.265145, 0.232956, 0.516599}, {0.263663, 0.237631, 0.518762},
  {0.262138, 0.242286, 0.520837}, {0.260571, 0.246922, 0.522828},
  {0.258965, 0.251537, 0.524736}, {0.257322, 0.256130, 0.526563},
  {0.255645, 0.260703, 0.528312}, {0.253935, 0.265254, 0.529983},
  {0.252194, 0.269783, 0.531579}, {0.250425, 0.274290, 0.533103},
  {0.248629, 0.278775, 0.534556}, {0.246811, 0.283237, 0.535941},
  {0.244972, 0.287675, 0.537260}, {0.243113, 0.292092, 0.538516},
  {0.241237, 0.296485, 0.539709}, {0.239346, 0.300855, 0.540844},
  {0.237441, 0.305202, 0.541921}, {0.235526, 0.309527, 0.542944},
  {0.233603, 0.313828, 0.543914}, {0.231674, 0.318106, 0.544834},
  {0.229739, 0.322361, 0.545706}, {0.227802, 0.326594, 0.546532},
  {0.225863, 0.330805, 0.547314}, {0.223925, 0.334994, 0.548053},
  {0.221989, 0.339161, 0.548752}, {0.220057, 0.343307, 0.549413},
  {0.218130, 0.347432, 0.550038}, {0.216210, 0.351535, 0.550627},
  {0.214298, 0.355619, 0.551184}, {0.212395, 0.359683, 0.551710},
  {0.210503, 0.363727, 0.552206}, {0.208623, 0.367752, 0.552675},
  {0.206756, 0.371758, 0.553117}, {0.204903, 0.375746, 0.553533},
  {0.203063, 0.379716, 0.553925}, {0.201239, 0.383670, 0.554294},
  {0.199430, 0.387607, 0.554642}, {0.197636, 0.391528, 0.554969},
  {0.195860, 0.395433, 0.555276}, {0.194100, 0.399323, 0.555565},
  {0.192357, 0.403199, 0.555836}, {0.190631, 0.407061, 0.556089},
  {0.188923, 0.410910, 0.556326}, {0.187231, 0.414746, 0.556547},
  {0.185556, 0.418570, 0.556753}, {0.183898, 0.422383, 0.556944},
  {0.182256, 0.426184, 0.557120}, {0.180629, 0.429975, 0.557282},
  {0.179019, 0.433756, 0.557430}, {0.177423, 0.437527, 0.557565},
  {0.175841, 0.441290, 0.557685}, {0.174274, 0.445044, 0.557792},
  {0.172719, 0.448791, 0.557885}, {0.171176, 0.452530, 0.557965},
  {0.169646, 0.456262, 0.558030}, {0.168126, 0.459988, 0.558082},
  {0.166617, 0.463708, 0.558119}, {0.165117, 0.467423, 0.558141},
  {0.163625, 0.471133, 0.558148}, {0.162142, 0.474838, 0.558140},
  {0.160665, 0.478540, 0.558115}, {0.159194, 0.482237, 0.558073},
  {0.157729, 0.485932, 0.558013}, {0.156270, 0.489624, 0.557936},
  {0.154815, 0.493313, 0.557840}, {0.153364, 0.497000, 0.557724},
  {0.151918, 0.500685, 0.557587}, {0.150476, 0.504369, 0.557430},
  {0.149039, 0.508051, 0.557250}, {0.147607, 0.511733, 0.557049},
  {0.146180, 0.515413, 0.556823}, {0.144759, 0.519093, 0.556572},
  {0.143343, 0.522773, 0.556295}, {0.141935, 0.526453, 0.555991},
  {0.140536, 0.530132, 0.555659}, {0.139147, 0.533812, 0.555298},
  {0.137770, 0.537492, 0.554906}, {0.136408, 0.541173, 0.554483},
  {0.135066, 0.544853, 0.554029}, {0.133743, 0.548535, 0.553541},
  {0.132444, 0.552216, 0.553018}, {0.131172, 0.555899, 0.552459},
  {0.129933, 0.559582, 0.551864}, {0.128729, 0.563265, 0.551229},
  {0.127568, 0.566949, 0.550556}, {0.126453, 0.570633, 0.549841},
  {0.125394, 0.574318, 0.549086}, {0.124395, 0.578002, 0.548287},
  {0.123463, 0.581687, 0.547445}, {0.122606, 0.585371, 0.546557},
  {0.121831, 0.589055, 0.545623}, {0.121148, 0.592739, 0.544641},
  {0.120565, 0.596422, 0.543611}, {0.120092, 0.600104, 0.542530},
  {0.119738, 0.603785, 0.541400}, {0.119512, 0.607464, 0.540218},
  {0.119423, 0.611141, 0.538982}, {0.119483, 0.614817, 0.537692},
  {0.119699, 0.618490, 0.536347}, {0.120081, 0.622161, 0.534946},
  {0.120638, 0.625828, 0.533488}, {0.121380, 0.629492, 0.531973},
  {0.122312, 0.633153, 0.530398}, {0.123444, 0.636809, 0.528763},
  {0.124780, 0.640461, 0.527068}, {0.126326, 0.644107, 0.525311},
  {0.128087, 0.647749, 0.523491}, {0.130067, 0.651384, 0.521608},
  {0.132268, 0.655014, 0.519661}, {0.134692, 0.658636, 0.517649},
  {0.137339, 0.662252, 0.515571}, {0.140210, 0.665859, 0.513427},
  {0.143303, 0.669459, 0.511215}, {0.146616, 0.673050, 0.508936},
  {0.150148, 0.676631, 0.506589}, {0.153894, 0.680203, 0.504172},
  {0.157851, 0.683765, 0.501686}, {0.162016, 0.687316, 0.499129},
  {0.166383, 0.690856, 0.496502}, {0.170948, 0.694384, 0.493803},
  {0.175707, 0.697900, 0.491033}, {0.180653, 0.701402, 0.488189},
  {0.185783, 0.704891, 0.485273}, {0.191090, 0.708366, 0.482284},
  {0.196571, 0.711827, 0.479221}, {0.202219, 0.715272, 0.476084},
  {0.208030, 0.718701, 0.472873}, {0.214000, 0.722114, 0.469588},
  {0.220124, 0.725509, 0.466226}, {0.226397, 0.728888, 0.462789},
  {0.232815, 0.732247, 0.459277}, {0.239374, 0.735588, 0.455688},
  {0.246070, 0.738910, 0.452024}, {0.252899, 0.742211, 0.448284},
  {0.259857, 0.745492, 0.444467}, {0.266941, 0.748751, 0.440573},
  {0.274149, 0.751988, 0.436601}, {0.281477, 0.755203, 0.432552},
  {0.288921, 0.758394, 0.428426}, {0.296479, 0.761561, 0.424223},
  {0.304148, 0.764704, 0.419943}, {0.311925, 0.767822, 0.415586},
  {0.319809, 0.770914, 0.411152}, {0.327796, 0.773980, 0.406640},
  {0.335885, 0.777018, 0.402049}, {0.344074, 0.780029, 0.397381},
  {0.352360, 0.783011, 0.392636}, {0.360741, 0.785964, 0.387814},
  {0.369214, 0.788888, 0.382914}, {0.377779, 0.791781, 0.377939},
  {0.386433, 0.794644, 0.372886}, {0.395174, 0.797475, 0.367757},
  {0.404001, 0.800275, 0.362552}, {0.412913, 0.803041, 0.357269},
  {0.421908, 0.805774, 0.351910}, {0.430983, 0.808473, 0.346476},
  {0.440137, 0.811138, 0.340967}, {0.449368, 0.813768, 0.335384},
  {0.458674, 0.816363, 0.329727}, {0.468053, 0.818921, 0.323998},
  {0.477504, 0.821444, 0.318195}, {0.487026, 0.823929, 0.312321},
  {0.496615, 0.826376, 0.306377}, {0.506271, 0.828786, 0.300362},
  {0.515992, 0.831158, 0.294279}, {0.525776, 0.833491, 0.288127},
  {0.535621, 0.835785, 0.281908}, {0.545524, 0.838039, 0.275626},
  {0.555484, 0.840254, 0.269281}, {0.565498, 0.842430, 0.262877},
  {0.575563, 0.844566, 0.256415}, {0.585678, 0.846661, 0.249897},
  {0.595839, 0.848717, 0.243329}, {0.606045, 0.850733, 0.236712},
  {0.616293, 0.852709, 0.230052}, {0.626579, 0.854645, 0.223353},
  {0.636902, 0.856542, 0.216620}, {0.647257, 0.858400, 0.209861},
  {0.657642, 0.860219, 0.203082}, {0.668054, 0.861999, 0.196293},
  {0.678489, 0.863742, 0.189503}, {0.688944, 0.865448, 0.182725},
  {0.699415, 0.867117, 0.175971}, {0.709898, 0.868751, 0.169257},
  {0.720391, 0.870350, 0.162603}, {0.730889, 0.871916, 0.156029},
  {0.741388, 0.873449, 0.149561}, {0.751884, 0.874951, 0.143228},
  {0.762373, 0.876424, 0.137064}, {0.772852, 0.877868, 0.131109},
  {0.783315, 0.879285, 0.125405}, {0.793760, 0.880678, 0.120005},
  {0.804182, 0.882046, 0.114965}, {0.814576, 0.883393, 0.110347},
  {0.824940, 0.884720, 0.106217}, {0.835270, 0.886029, 0.102646},
  {0.845561, 0.887322, 0.099702}, {0.855810, 0.888601, 0.097452},
  {0.866013, 0.889868, 0.095953}, {0.876168, 0.891125, 0.095250},
  {0.886271, 0.892374, 0.095374}, {0.896320, 0.893616, 0.096335},
  {0.906311, 0.894855, 0.098125}, {0.916242, 0.896091, 0.100717},
  {0.926106, 0.897330, 0.104071}, {0.935904, 0.898570, 0.108131},
  {0.945636, 0.899815, 0.112838}, {0.955300, 0.901065, 0.118128},
  {0.964894, 0.902323, 0.123941}, {0.974417, 0.903590, 0.130215},
  {0.983868, 0.904867, 0.136897}, {0.993248, 0.906157, 0.143936}};
 
// Copyright 2019 Google LLC.
// SPDX-License-Identifier: Apache-2.0
// Author: Anton Mikhailov
// The look-up tables contains 256 entries. Each entry is a an sRGB triplet.
static double _turbo_data[][3] = {
  {0.18995, 0.07176, 0.23217}, {0.19483, 0.08339, 0.26149},
  {0.19956, 0.09498, 0.29024}, {0.20415, 0.10652, 0.31844},
  {0.20860, 0.11802, 0.34607}, {0.21291, 0.12947, 0.37314},
  {0.21708, 0.14087, 0.39964}, {0.22111, 0.15223, 0.42558},
  {0.22500, 0.16354, 0.45096}, {0.22875, 0.17481, 0.47578},
  {0.23236, 0.18603, 0.50004}, {0.23582, 0.19720, 0.52373},
  {0.23915, 0.20833, 0.54686}, {0.24234, 0.21941, 0.56942},
  {0.24539, 0.23044, 0.59142}, {0.24830, 0.24143, 0.61286},
  {0.25107, 0.25237, 0.63374}, {0.25369, 0.26327, 0.65406},
  {0.25618, 0.27412, 0.67381}, {0.25853, 0.28492, 0.69300},
  {0.26074, 0.29568, 0.71162}, {0.26280, 0.30639, 0.72968},
  {0.26473, 0.31706, 0.74718}, {0.26652, 0.32768, 0.76412},
  {0.26816, 0.33825, 0.78050}, {0.26967, 0.34878, 0.79631},
  {0.27103, 0.35926, 0.81156}, {0.27226, 0.36970, 0.82624},
  {0.27334, 0.38008, 0.84037}, {0.27429, 0.39043, 0.85393},
  {0.27509, 0.40072, 0.86692}, {0.27576, 0.41097, 0.87936},
  {0.27628, 0.42118, 0.89123}, {0.27667, 0.43134, 0.90254},
  {0.27691, 0.44145, 0.91328}, {0.27701, 0.45152, 0.92347},
  {0.27698, 0.46153, 0.93309}, {0.27680, 0.47151, 0.94214},
  {0.27648, 0.48144, 0.95064}, {0.27603, 0.49132, 0.95857},
  {0.27543, 0.50115, 0.96594}, {0.27469, 0.51094, 0.97275},
  {0.27381, 0.52069, 0.97899}, {0.27273, 0.53040, 0.98461},
  {0.27106, 0.54015, 0.98930}, {0.26878, 0.54995, 0.99303},
  {0.26592, 0.55979, 0.99583}, {0.26252, 0.56967, 0.99773},
  {0.25862, 0.57958, 0.99876}, {0.25425, 0.58950, 0.99896},
  {0.24946, 0.59943, 0.99835}, {0.24427, 0.60937, 0.99697},
  {0.23874, 0.61931, 0.99485}, {0.23288, 0.62923, 0.99202},
  {0.22676, 0.63913, 0.98851}, {0.22039, 0.64901, 0.98436},
  {0.21382, 0.65886, 0.97959}, {0.20708, 0.66866, 0.97423},
  {0.20021, 0.67842, 0.96833}, {0.19326, 0.68812, 0.96190},
  {0.18625, 0.69775, 0.95498}, {0.17923, 0.70732, 0.94761},
  {0.17223, 0.71680, 0.93981}, {0.16529, 0.72620, 0.93161},
  {0.15844, 0.73551, 0.92305}, {0.15173, 0.74472, 0.91416},
  {0.14519, 0.75381, 0.90496}, {0.13886, 0.76279, 0.89550},
  {0.13278, 0.77165, 0.88580}, {0.12698, 0.78037, 0.87590},
  {0.12151, 0.78896, 0.86581}, {0.11639, 0.79740, 0.85559},
  {0.11167, 0.80569, 0.84525}, {0.10738, 0.81381, 0.83484},
  {0.10357, 0.82177, 0.82437}, {0.10026, 0.82955, 0.81389},
  {0.09750, 0.83714, 0.80342}, {0.09532, 0.84455, 0.79299},
  {0.09377, 0.85175, 0.78264}, {0.09287, 0.85875, 0.77240},
  {0.09267, 0.86554, 0.76230}, {0.09320, 0.87211, 0.75237},
  {0.09451, 0.87844, 0.74265}, {0.09662, 0.88454, 0.73316},
  {0.09958, 0.89040, 0.72393}, {0.10342, 0.89600, 0.71500},
  {0.10815, 0.90142, 0.70599}, {0.11374, 0.90673, 0.69651},
  {0.12014, 0.91193, 0.68660}, {0.12733, 0.91701, 0.67627},
  {0.13526, 0.92197, 0.66556}, {0.14391, 0.92680, 0.65448},
  {0.15323, 0.93151, 0.64308}, {0.16319, 0.93609, 0.63137},
  {0.17377, 0.94053, 0.61938}, {0.18491, 0.94484, 0.60713},
  {0.19659, 0.94901, 0.59466}, {0.20877, 0.95304, 0.58199},
  {0.22142, 0.95692, 0.56914}, {0.23449, 0.96065, 0.55614},
  {0.24797, 0.96423, 0.54303}, {0.26180, 0.96765, 0.52981},
  {0.27597, 0.97092, 0.51653}, {0.29042, 0.97403, 0.50321},
  {0.30513, 0.97697, 0.48987}, {0.32006, 0.97974, 0.47654},
  {0.33517, 0.98234, 0.46325}, {0.35043, 0.98477, 0.45002},
  {0.36581, 0.98702, 0.43688}, {0.38127, 0.98909, 0.42386},
  {0.39678, 0.99098, 0.41098}, {0.41229, 0.99268, 0.39826},
  {0.42778, 0.99419, 0.38575}, {0.44321, 0.99551, 0.37345},
  {0.45854, 0.99663, 0.36140}, {0.47375, 0.99755, 0.34963},
  {0.48879, 0.99828, 0.33816}, {0.50362, 0.99879, 0.32701},
  {0.51822, 0.99910, 0.31622}, {0.53255, 0.99919, 0.30581},
  {0.54658, 0.99907, 0.29581}, {0.56026, 0.99873, 0.28623},
  {0.57357, 0.99817, 0.27712}, {0.58646, 0.99739, 0.26849},
  {0.59891, 0.99638, 0.26038}, {0.61088, 0.99514, 0.25280},
  {0.62233, 0.99366, 0.24579}, {0.63323, 0.99195, 0.23937},
  {0.64362, 0.98999, 0.23356}, {0.65394, 0.98775, 0.22835},
  {0.66428, 0.98524, 0.22370}, {0.67462, 0.98246, 0.21960},
  {0.68494, 0.97941, 0.21602}, {0.69525, 0.97610, 0.21294},
  {0.70553, 0.97255, 0.21032}, {0.71577, 0.96875, 0.20815},
  {0.72596, 0.96470, 0.20640}, {0.73610, 0.96043, 0.20504},
  {0.74617, 0.95593, 0.20406}, {0.75617, 0.95121, 0.20343},
  {0.76608, 0.94627, 0.20311}, {0.77591, 0.94113, 0.20310},
  {0.78563, 0.93579, 0.20336}, {0.79524, 0.93025, 0.20386},
  {0.80473, 0.92452, 0.20459}, {0.81410, 0.91861, 0.20552},
  {0.82333, 0.91253, 0.20663}, {0.83241, 0.90627, 0.20788},
  {0.84133, 0.89986, 0.20926}, {0.85010, 0.89328, 0.21074},
  {0.85868, 0.88655, 0.21230}, {0.86709, 0.87968, 0.21391},
  {0.87530, 0.87267, 0.21555}, {0.88331, 0.86553, 0.21719},
  {0.89112, 0.85826, 0.21880}, {0.89870, 0.85087, 0.22038},
  {0.90605, 0.84337, 0.22188}, {0.91317, 0.83576, 0.22328},
  {0.92004, 0.82806, 0.22456}, {0.92666, 0.82025, 0.22570},
  {0.93301, 0.81236, 0.22667}, {0.93909, 0.80439, 0.22744},
  {0.94489, 0.79634, 0.22800}, {0.95039, 0.78823, 0.22831},
  {0.95560, 0.78005, 0.22836}, {0.96049, 0.77181, 0.22811},
  {0.96507, 0.76352, 0.22754}, {0.96931, 0.75519, 0.22663},
  {0.97323, 0.74682, 0.22536}, {0.97679, 0.73842, 0.22369},
  {0.98000, 0.73000, 0.22161}, {0.98289, 0.72140, 0.21918},
  {0.98549, 0.71250, 0.21650}, {0.98781, 0.70330, 0.21358},
  {0.98986, 0.69382, 0.21043}, {0.99163, 0.68408, 0.20706},
  {0.99314, 0.67408, 0.20348}, {0.99438, 0.66386, 0.19971},
  {0.99535, 0.65341, 0.19577}, {0.99607, 0.64277, 0.19165},
  {0.99654, 0.63193, 0.18738}, {0.99675, 0.62093, 0.18297},
  {0.99672, 0.60977, 0.17842}, {0.99644, 0.59846, 0.17376},
  {0.99593, 0.58703, 0.16899}, {0.99517, 0.57549, 0.16412},
  {0.99419, 0.56386, 0.15918}, {0.99297, 0.55214, 0.15417},
  {0.99153, 0.54036, 0.14910}, {0.98987, 0.52854, 0.14398},
  {0.98799, 0.51667, 0.13883}, {0.98590, 0.50479, 0.13367},
  {0.98360, 0.49291, 0.12849}, {0.98108, 0.48104, 0.12332},
  {0.97837, 0.46920, 0.11817}, {0.97545, 0.45740, 0.11305},
  {0.97234, 0.44565, 0.10797}, {0.96904, 0.43399, 0.10294},
  {0.96555, 0.42241, 0.09798}, {0.96187, 0.41093, 0.09310},
  {0.95801, 0.39958, 0.08831}, {0.95398, 0.38836, 0.08362},
  {0.94977, 0.37729, 0.07905}, {0.94538, 0.36638, 0.07461},
  {0.94084, 0.35566, 0.07031}, {0.93612, 0.34513, 0.06616},
  {0.93125, 0.33482, 0.06218}, {0.92623, 0.32473, 0.05837},
  {0.92105, 0.31489, 0.05475}, {0.91572, 0.30530, 0.05134},
  {0.91024, 0.29599, 0.04814}, {0.90463, 0.28696, 0.04516},
  {0.89888, 0.27824, 0.04243}, {0.89298, 0.26981, 0.03993},
  {0.88691, 0.26152, 0.03753}, {0.88066, 0.25334, 0.03521},
  {0.87422, 0.24526, 0.03297}, {0.86760, 0.23730, 0.03082},
  {0.86079, 0.22945, 0.02875}, {0.85380, 0.22170, 0.02677},
  {0.84662, 0.21407, 0.02487}, {0.83926, 0.20654, 0.02305},
  {0.83172, 0.19912, 0.02131}, {0.82399, 0.19182, 0.01966},
  {0.81608, 0.18462, 0.01809}, {0.80799, 0.17753, 0.01660},
  {0.79971, 0.17055, 0.01520}, {0.79125, 0.16368, 0.01387},
  {0.78260, 0.15693, 0.01264}, {0.77377, 0.15028, 0.01148},
  {0.76476, 0.14374, 0.01041}, {0.75556, 0.13731, 0.00942},
  {0.74617, 0.13098, 0.00851}, {0.73661, 0.12477, 0.00769},
  {0.72686, 0.11867, 0.00695}, {0.71692, 0.11268, 0.00629},
  {0.70680, 0.10680, 0.00571}, {0.69650, 0.10102, 0.00522},
  {0.68602, 0.09536, 0.00481}, {0.67535, 0.08980, 0.00449},
  {0.66449, 0.08436, 0.00424}, {0.65345, 0.07902, 0.00408},
  {0.64223, 0.07380, 0.00401}, {0.63082, 0.06868, 0.00401},
  {0.61923, 0.06367, 0.00410}, {0.60746, 0.05878, 0.00427},
  {0.59550, 0.05399, 0.00453}, {0.58336, 0.04931, 0.00486},
  {0.57103, 0.04474, 0.00529}, {0.55852, 0.04028, 0.00579},
  {0.54583, 0.03593, 0.00638}, {0.53295, 0.03169, 0.00705},
  {0.51989, 0.02756, 0.00780}, {0.50664, 0.02354, 0.00863},
  {0.49321, 0.01963, 0.00955}, {0.47960, 0.01583, 0.01055}};
 
void ColorTable_Recompute(GmshColorTable *ct)
{
  double s, t, gamma;
  int r, g, b, a;
 
  double bias = ct->dpar[COLORTABLE_BIAS];
  double curvature = ct->dpar[COLORTABLE_CURVATURE];
  int rotation = ct->ipar[COLORTABLE_ROTATION];
 
  // resize fixed-size colormaps:
  switch(ct->ipar[COLORTABLE_NUMBER]) {
  case 20: ct->size = sizeof(_magma_data) / (3 * sizeof(double)); break;
  case 21: ct->size = sizeof(_inferno_data) / (3 * sizeof(double)); break;
  case 22: ct->size = sizeof(_plasma_data) / (3 * sizeof(double)); break;
  case 23: ct->size = sizeof(_viridis_data) / (3 * sizeof(double)); break;
  case 24: ct->size = sizeof(_turbo_data) / (3 * sizeof(double)); break;
  }
 
  for(int i = 0; i < ct->size; i++) {
    if(ct->size > 1) {
      if(i + rotation < 0)
        s = (double)(i + rotation + ct->size) / (double)(ct->size - 1);
      else if(i + rotation > ct->size - 1)
        s = (double)(i + rotation - ct->size) / (double)(ct->size - 1);
      else
        s = (double)(i + rotation) / (double)(ct->size - 1);
    }
    else
      s = 0.;
 
    if(ct->ipar[COLORTABLE_SWAP]) s = 1.0 - s;
 
    switch(ct->ipar[COLORTABLE_NUMBER]) {
    case 0: // all black
      r = g = b = 0;
      break;
    case 1: // vis5d
      t = (curvature + 1.4) * (s - (1. + bias) / 2.);
      r = (int)(128.0 + 127.0 * atan(7.0 * t) / 1.57);
      g = (int)(128.0 + 127.0 * (2 * exp(-7 * t * t) - 1));
      b = (int)(128.0 + 127.0 * atan(-7.0 * t) / 1.57);
      break;
    case 2: // matlab "jet"
    {
      double ii = (double)(s - bias) * 128.;
      if(ii < 0) ii = 0;
      if(ii > 128) ii = 128;
      double rr = ii <= 46  ? 0. :
                  ii >= 111 ? -0.03125 * (ii - 111) + 1. :
                  ii >= 78  ? 1. :
                              0.03125 * (ii - 46);
      double gg = ii <= 14 || ii >= 111 ? 0. :
                  ii >= 79              ? -0.03125 * (ii - 111) :
                  ii <= 46              ? 0.03125 * (ii - 14) :
                                          1.;
      double bb = ii >= 79 ? 0. :
                  ii >= 47 ? -0.03125 * (ii - 79) :
                  ii <= 14 ? 0.03125 * (ii - 14) + 1. :
                             1.;
      r = (int)(rr * 255.);
      g = (int)(gg * 255.);
      b = (int)(bb * 255.);
    } break;
    case 3: // lucie, samcef (?)
      if(s - bias <= 0.) {
        r = 0;
        g = 0;
        b = 255;
      }
      else if(s - bias <= 0.40) {
        r = 0;
        g = (int)((s - bias) * 637.5);
        b = (int)(255. - (s - bias) * 637.5);
      }
      else if(s - bias <= 0.60) {
        r = (int)(1275. * (s - bias - 0.4));
        g = 255;
        b = 0;
      }
      else if(s - bias <= 1.) {
        r = 255;
        g = (int)(255. - 637.5 * (s - bias - 0.6));
        b = 0;
      }
      else {
        r = 255;
        g = 0;
        b = 0;
      }
      break;
    case 4: // rainbow
      if(s - bias <= 0.) {
        r = 0;
        g = 0;
        b = 255;
      }
      else if(s - bias <= 0.25 + curvature) {
        curvature = (curvature == -0.25) ? -0.26 : curvature;
        r = 0;
        g = (int)((s - bias) * (255. / (0.25 + curvature)));
        b = 255;
      }
      else if(s - bias <= 0.50) {
        curvature = (curvature == 0.25) ? 0.26 : curvature;
        r = 0;
        g = 255;
        b = (int)(255. -
                  (255. / (0.25 - curvature)) * (s - bias - 0.25 - curvature));
      }
      else if(s - bias <= 0.75 - curvature) {
        curvature = (curvature == 0.25) ? 0.26 : curvature;
        r = (int)((s - bias - 0.5) * (255. / (0.25 - curvature)));
        g = 255;
        b = 0;
      }
      else if(s - bias <= 1.) {
        curvature = (curvature == -0.25) ? -0.26 : curvature;
        r = 255;
        g = (int)(255. -
                  (255. / (0.25 + curvature)) * (s - bias - 0.75 + curvature));
        b = 0;
      }
      else {
        r = 255;
        g = 0;
        b = 0;
      }
      break;
    case 5: // emc2000 (rainbow with black and white)
      if(s - bias <= 0.) {
        r = 0;
        g = 0;
        b = 0;
      }
      else if(s - bias <= 0.2) {
        r = (int)(57 * (1 - 100 * ((s - bias) - 0.1) * ((s - bias) - 0.1)));
        g = 0;
        b = (int)((s - bias) * (255. / 0.2));
      }
      else if(s - bias <= 0.3624) {
        r = 0;
        g = (int)((s - bias - 0.2) * (255. / 0.1624));
        b = 255;
      }
      else if(s - bias <= 0.50) {
        r = 0;
        g = 255;
        b = (int)(255. - (255. / 0.1376) * (s - bias - 0.3624));
      }
      else if(s - bias <= 0.6376) {
        r = (int)((s - bias - 0.5) * (255. / 0.1376));
        g = 255;
        b = 0;
      }
      else if(s - bias <= 0.8) {
        r = 255;
        g = (int)(255. - (255. / 0.1624) * (s - bias - 0.6376));
        b = 0;
      }
      else if(s - bias <= 1.0) {
        r = 255;
        g = (int)((255. / 0.2) * (s - bias - 0.8));
        b = (int)(-3187.66 * (s - bias) * (s - bias) + 7012.76 * (s - bias) -
                  3570.61);
      }
      else {
        r = 255;
        g = 255;
        b = 255;
      }
      break;
    case 6: // incandescent (darkblue->red->yellow->white)
      r =
        (int)(255. * cubic(-0.0506169, 2.81633, -1.87033, 0.0524573, s - bias));
      g = (int)(255. * cubic(0.0485868, -1.26109, 6.3074, -4.12498, s - bias));
      b = (int)(255. * cubic(0.364662, 1.50814, -7.36756, 6.51847, s - bias));
      break;
    case 7: // matlab "hot"
      r = (int)(255. * hot_r(s - bias));
      g = (int)(255. * hot_g(s - bias));
      b = (int)(255. * hot_b(s - bias));
      break;
    case 8: // matlab "pink"
      r = (int)(255. * sqrt((2. * gray(s - bias) + hot_r(s - bias)) / 3.));
      g = (int)(255. * sqrt((2. * gray(s - bias) + hot_g(s - bias)) / 3.));
      b = (int)(255. * sqrt((2. * gray(s - bias) + hot_b(s - bias)) / 3.));
      break;
    case 9: // grayscale
      if(s - bias <= 0.) { r = g = b = 0; }
      else if(s - bias <= 1.) {
        r = g = b = (int)(255 * (1. - curvature) * (s - bias));
      }
      else {
        r = g = b = (int)(255 * (1. - curvature));
      }
      break;
    case 10: // "french flag"
    {
      double ii = (double)(s - bias);
      if(ii < 0) ii = 0;
      if(ii > 1) ii = 1;
      double rr = ii >= .75 ? 2 * (0.75 - ii) + 1. :
                  ii >= .5  ? 1. :
                  ii >= .25 ? 4. * (ii - 0.25) :
                              0.;
      double gg = ii <= .25 ? 1.33333 * ii :
                  ii <= .5  ? 0.33333 + 2.66667 * (ii - 0.25) :
                  ii <= .75 ? 1 - 2.66667 * (ii - 0.5) :
                              1.33333 * (1. - ii);
      double bb = ii <= 0.25 ? 2 * ii + 0.5 :
                  ii <= 0.5  ? 1. :
                  ii <= 0.75 ? 4 * (0.75 - ii) :
                               0.;
      r = (int)(rr * 255.);
      g = (int)(gg * 255.);
      b = (int)(bb * 255.);
    } break;
    case 11: // matlab "hsv"
    {
      double H = 6. * s + 1.e-10, R, G, B;
      HSV_to_RGB(H, 1., 1., &R, &G, &B);
      r = (int)(255 * R);
      g = (int)(255 * G);
      b = (int)(255 * B);
    } break;
    case 12: // spectrum (truncated hsv)
    {
      double H = 5. * s + 1.e-10, R, G, B;
      HSV_to_RGB(H, 1., 1., &R, &G, &B);
      r = (int)(255 * R);
      g = (int)(255 * G);
      b = (int)(255 * B);
    } break;
    case 13: // matlab "bone"
      r = (int)(255. * (7. * gray(s - bias) + hot_b(s - bias)) / 8.);
      g = (int)(255. * (7. * gray(s - bias) + hot_g(s - bias)) / 8.);
      b = (int)(255. * (7. * gray(s - bias) + hot_r(s - bias)) / 8.);
      break;
    case 14: // matlab "spring"
      r = (int)(255. * 1.);
      g = (int)(255. * gray(s - bias));
      b = (int)(255. * (1. - gray(s - bias)));
      break;
    case 15: // matlab "summer"
      r = (int)(255. * gray(s - bias));
      g = (int)(255. * (0.5 + gray(s - bias) / 2.));
      b = (int)(255. * 0.4);
      break;
    case 16: // matlab "autumn"
      r = (int)(255. * 1.);
      g = (int)(255. * gray(s - bias));
      b = (int)(255. * 0.);
      break;
    case 17: // matlab "winter"
      r = (int)(255. * 0.);
      g = (int)(255. * gray(s - bias));
      b = (int)(255. * (0.5 + (1. - gray(s - bias)) / 2.));
      break;
    case 18: // matlab "cool"
      r = (int)(255. * gray(s - bias));
      g = (int)(255. * (1. - gray(s - bias)));
      b = (int)(255. * 1.);
      break;
    case 19: // matlab "copper"
      r = (int)(255. * std::min(1., gray(s - bias) * 1.25));
      g = (int)(255. * std::min(1., gray(s - bias) * 0.7812));
      b = (int)(255. * std::min(1., gray(s - bias) * 0.4975));
      break;
    case 20: // matplotlib "magma"
      r = (int)(255. * _magma_data[i][0]);
      g = (int)(255. * _magma_data[i][1]);
      b = (int)(255. * _magma_data[i][2]);
      break;
    case 21: // matplotlib "inferno"
      r = (int)(255. * _inferno_data[i][0]);
      g = (int)(255. * _inferno_data[i][1]);
      b = (int)(255. * _inferno_data[i][2]);
      break;
    case 22: // matplotlib "plasma"
      r = (int)(255. * _plasma_data[i][0]);
      g = (int)(255. * _plasma_data[i][1]);
      b = (int)(255. * _plasma_data[i][2]);
      break;
    case 23: // matplotlib "viridis"
      r = (int)(255. * _viridis_data[i][0]);
      g = (int)(255. * _viridis_data[i][1]);
      b = (int)(255. * _viridis_data[i][2]);
      break;
    case 24: // google "turbo"
      r = (int)(255. * _turbo_data[i][0]);
      g = (int)(255. * _turbo_data[i][1]);
      b = (int)(255. * _turbo_data[i][2]);
      break;
    default: r = g = b = 0; break;
    }
 
    double aa = 1.0;
    if(ct->dpar[COLORTABLE_ALPHAPOW])
      aa = pow(s ? s : 1.e-10, ct->dpar[COLORTABLE_ALPHAPOW]);
    a = (int)(255. * aa * ct->dpar[COLORTABLE_ALPHA]);
 
    if(ct->dpar[COLORTABLE_BETA]) {
      if(ct->dpar[COLORTABLE_BETA] > 0.0)
        gamma = 1. - ct->dpar[COLORTABLE_BETA];
      else
        gamma =
          1. /
          (1.001 + ct->dpar[COLORTABLE_BETA]); // beta is thresholded to [-1,1]
      r = (int)(255. * pow((double)r / 255., gamma));
      g = (int)(255. * pow((double)g / 255., gamma));
      b = (int)(255. * pow((double)b / 255., gamma));
    }
 
    if(ct->ipar[COLORTABLE_INVERT]) {
      r = 255 - r;
      g = 255 - g;
      b = 255 - b;
    }
 
    // clamp to [0,255]
    r = r < 0 ? 0 : (r > 255 ? 255 : r);
    g = g < 0 ? 0 : (g > 255 ? 255 : g);
    b = b < 0 ? 0 : (b > 255 ? 255 : b);
    a = a < 0 ? 0 : (a > 255 ? 255 : a);
 
    ct->table[i] = CTX::instance()->packColor(r, g, b, a);
  }
}
 
static GmshColorTable clip;
 
void ColorTable_Copy(GmshColorTable *ct)
{
  clip.size = ct->size;
  memcpy(clip.table, ct->table, ct->size * sizeof(unsigned int));
  memcpy(clip.ipar, ct->ipar, COLORTABLE_NBMAX_PARAM * sizeof(int));
  memcpy(clip.dpar, ct->dpar, COLORTABLE_NBMAX_PARAM * sizeof(double));
}
 
void ColorTable_Paste(GmshColorTable *ct)
{
  ct->size = clip.size;
  memcpy(ct->table, clip.table, clip.size * sizeof(unsigned int));
  memcpy(ct->ipar, clip.ipar, COLORTABLE_NBMAX_PARAM * sizeof(int));
  memcpy(ct->dpar, clip.dpar, COLORTABLE_NBMAX_PARAM * sizeof(double));
}
 
int ColorTable_Diff(GmshColorTable *ct1, GmshColorTable *ct2)
{
  if(ct1->size != ct2->size) return 1;
  for(int i = 0; i < ct1->size; i++)
    if(ct1->table[i] != ct2->table[i]) return 1;
  return 0;
}
 
void ColorTable_Print(GmshColorTable *ct, FILE *fp,
                      std::vector<std::string> *vec)
{
  int i, r, g, b, a;
  char tmp1[1024], tmp2[1024];
 
  strcpy(tmp1, "");
  for(i = 0; i < ct->size; i++) {
    r = CTX::instance()->unpackRed(ct->table[i]);
    g = CTX::instance()->unpackGreen(ct->table[i]);
    b = CTX::instance()->unpackBlue(ct->table[i]);
    a = CTX::instance()->unpackAlpha(ct->table[i]);
    if(i && !(i % 4)) {
      if(fp)
        fprintf(fp, "%s\n", tmp1);
      else if(vec)
        vec->push_back(tmp1);
      else
        Msg::Direct(tmp1);
      strcpy(tmp1, "");
    }
    sprintf(tmp2, "{%d, %d, %d, %d}", r, g, b, a);
    strcat(tmp1, tmp2);
    if(i != ct->size - 1) strcat(tmp1, ", ");
  }
  if(fp)
    fprintf(fp, "%s\n", tmp1);
  else if(vec)
    vec->push_back(tmp1);
  else
    Msg::Direct(tmp1);
}
 
int ColorTable_IsAlpha(GmshColorTable *ct)
{
  int i, a;
  for(i = 0; i < ct->size; i++) {
    a = CTX::instance()->unpackAlpha(ct->table[i]);
    if(a < 255) return 1;
  }
  return 0;
}
 
// HSV/RBG conversion routines
 
void HSV_to_RGB(double H, double S, double V, double *R, double *G, double *B)
{
  if(S < 5.0e-6) { *R = *G = *B = V; }
  else {
    int i = (int)H;
    double f = H - (float)i;
    double p1 = V * (1.0 - S);
    double p2 = V * (1.0 - S * f);
    double p3 = V * (1.0 - S * (1.0 - f));
    switch(i) {
    case 0:
      *R = V;
      *G = p3;
      *B = p1;
      break;
    case 1:
      *R = p2;
      *G = V;
      *B = p1;
      break;
    case 2:
      *R = p1;
      *G = V;
      *B = p3;
      break;
    case 3:
      *R = p1;
      *G = p2;
      *B = V;
      break;
    case 4:
      *R = p3;
      *G = p1;
      *B = V;
      break;
    case 5:
      *R = V;
      *G = p1;
      *B = p2;
      break;
    default:
      *R = V;
      *G = V;
      *B = V;
      break;
    }
  }
}
 
void RGB_to_HSV(double R, double G, double B, double *H, double *S, double *V)
{
  double maxv = R > G ? R : G;
  if(B > maxv) maxv = B;
  *V = maxv;
  if(maxv > 0) {
    double minv = R < G ? R : G;
    if(B < minv) minv = B;
    *S = 1.0 - double(minv) / maxv;
    if(maxv > minv) {
      if(maxv == R) {
        *H = (G - B) / double(maxv - minv);
        if(*H < 0) *H += 6.0;
      }
      else if(maxv == G)
        *H = 2.0 + (B - R) / double(maxv - minv);
      else
        *H = 4.0 + (R - G) / double(maxv - minv);
    }
  }
}