Black body colors table?

[zvezdochiot]

Hi all.

Maybe it's worth replacing the black body colors table with an approximation?

redshift/src/colorramp.c

Lines 30 to 273 in 490ba2a

	static const float blackbody_color[] = {
	1.00000000, 0.18172716, 0.00000000, /* 1000K */
	1.00000000, 0.25503671, 0.00000000, /* 1100K */
	1.00000000, 0.30942099, 0.00000000, /* 1200K */
	1.00000000, 0.35357379, 0.00000000, /* ... */
	1.00000000, 0.39091524, 0.00000000,
	1.00000000, 0.42322816, 0.00000000,
	1.00000000, 0.45159884, 0.00000000,
	1.00000000, 0.47675916, 0.00000000,
	1.00000000, 0.49923747, 0.00000000,
	1.00000000, 0.51943421, 0.00000000,
	1.00000000, 0.54360078, 0.08679949,
	1.00000000, 0.56618736, 0.14065513,
	1.00000000, 0.58734976, 0.18362641,
	1.00000000, 0.60724493, 0.22137978,
	1.00000000, 0.62600248, 0.25591950,
	1.00000000, 0.64373109, 0.28819679,
	1.00000000, 0.66052319, 0.31873863,
	1.00000000, 0.67645822, 0.34786758,
	1.00000000, 0.69160518, 0.37579588,
	1.00000000, 0.70602449, 0.40267128,
	1.00000000, 0.71976951, 0.42860152,
	1.00000000, 0.73288760, 0.45366838,
	1.00000000, 0.74542112, 0.47793608,
	1.00000000, 0.75740814, 0.50145662,
	1.00000000, 0.76888303, 0.52427322,
	1.00000000, 0.77987699, 0.54642268,
	1.00000000, 0.79041843, 0.56793692,
	1.00000000, 0.80053332, 0.58884417,
	1.00000000, 0.81024551, 0.60916971,
	1.00000000, 0.81957693, 0.62893653,
	1.00000000, 0.82854786, 0.64816570,
	1.00000000, 0.83717703, 0.66687674,
	1.00000000, 0.84548188, 0.68508786,
	1.00000000, 0.85347859, 0.70281616,
	1.00000000, 0.86118227, 0.72007777,
	1.00000000, 0.86860704, 0.73688797,
	1.00000000, 0.87576611, 0.75326132,
	1.00000000, 0.88267187, 0.76921169,
	1.00000000, 0.88933596, 0.78475236,
	1.00000000, 0.89576933, 0.79989606,
	1.00000000, 0.90198230, 0.81465502,
	1.00000000, 0.90963069, 0.82838210,
	1.00000000, 0.91710889, 0.84190889,
	1.00000000, 0.92441842, 0.85523742,
	1.00000000, 0.93156127, 0.86836903,
	1.00000000, 0.93853986, 0.88130458,
	1.00000000, 0.94535695, 0.89404470,
	1.00000000, 0.95201559, 0.90658983,
	1.00000000, 0.95851906, 0.91894041,
	1.00000000, 0.96487079, 0.93109690,
	1.00000000, 0.97107439, 0.94305985,
	1.00000000, 0.97713351, 0.95482993,
	1.00000000, 0.98305189, 0.96640795,
	1.00000000, 0.98883326, 0.97779486,
	1.00000000, 0.99448139, 0.98899179,
	1.00000000, 1.00000000, 1.00000000, /* 6500K */
	0.98947904, 0.99348723, 1.00000000,
	0.97940448, 0.98722715, 1.00000000,
	0.96975025, 0.98120637, 1.00000000,
	0.96049223, 0.97541240, 1.00000000,
	0.95160805, 0.96983355, 1.00000000,
	0.94303638, 0.96443333, 1.00000000,
	0.93480451, 0.95923080, 1.00000000,
	0.92689056, 0.95421394, 1.00000000,
	0.91927697, 0.94937330, 1.00000000,
	0.91194747, 0.94470005, 1.00000000,
	0.90488690, 0.94018594, 1.00000000,
	0.89808115, 0.93582323, 1.00000000,
	0.89151710, 0.93160469, 1.00000000,
	0.88518247, 0.92752354, 1.00000000,
	0.87906581, 0.92357340, 1.00000000,
	0.87315640, 0.91974827, 1.00000000,
	0.86744421, 0.91604254, 1.00000000,
	0.86191983, 0.91245088, 1.00000000,
	0.85657444, 0.90896831, 1.00000000,
	0.85139976, 0.90559011, 1.00000000,
	0.84638799, 0.90231183, 1.00000000,
	0.84153180, 0.89912926, 1.00000000,
	0.83682430, 0.89603843, 1.00000000,
	0.83225897, 0.89303558, 1.00000000,
	0.82782969, 0.89011714, 1.00000000,
	0.82353066, 0.88727974, 1.00000000,
	0.81935641, 0.88452017, 1.00000000,
	0.81530175, 0.88183541, 1.00000000,
	0.81136180, 0.87922257, 1.00000000,
	0.80753191, 0.87667891, 1.00000000,
	0.80380769, 0.87420182, 1.00000000,
	0.80018497, 0.87178882, 1.00000000,
	0.79665980, 0.86943756, 1.00000000,
	0.79322843, 0.86714579, 1.00000000,
	0.78988728, 0.86491137, 1.00000000, /* 10000K */
	0.78663296, 0.86273225, 1.00000000,
	0.78346225, 0.86060650, 1.00000000,
	0.78037207, 0.85853224, 1.00000000,
	0.77735950, 0.85650771, 1.00000000,
	0.77442176, 0.85453121, 1.00000000,
	0.77155617, 0.85260112, 1.00000000,
	0.76876022, 0.85071588, 1.00000000,
	0.76603147, 0.84887402, 1.00000000,
	0.76336762, 0.84707411, 1.00000000,
	0.76076645, 0.84531479, 1.00000000,
	0.75822586, 0.84359476, 1.00000000,
	0.75574383, 0.84191277, 1.00000000,
	0.75331843, 0.84026762, 1.00000000,
	0.75094780, 0.83865816, 1.00000000,
	0.74863017, 0.83708329, 1.00000000,
	0.74636386, 0.83554194, 1.00000000,
	0.74414722, 0.83403311, 1.00000000,
	0.74197871, 0.83255582, 1.00000000,
	0.73985682, 0.83110912, 1.00000000,
	0.73778012, 0.82969211, 1.00000000,
	0.73574723, 0.82830393, 1.00000000,
	0.73375683, 0.82694373, 1.00000000,
	0.73180765, 0.82561071, 1.00000000,
	0.72989845, 0.82430410, 1.00000000,
	0.72802807, 0.82302316, 1.00000000,
	0.72619537, 0.82176715, 1.00000000,
	0.72439927, 0.82053539, 1.00000000,
	0.72263872, 0.81932722, 1.00000000,
	0.72091270, 0.81814197, 1.00000000,
	0.71922025, 0.81697905, 1.00000000,
	0.71756043, 0.81583783, 1.00000000,
	0.71593234, 0.81471775, 1.00000000,
	0.71433510, 0.81361825, 1.00000000,
	0.71276788, 0.81253878, 1.00000000,
	0.71122987, 0.81147883, 1.00000000,
	0.70972029, 0.81043789, 1.00000000,
	0.70823838, 0.80941546, 1.00000000,
	0.70678342, 0.80841109, 1.00000000,
	0.70535469, 0.80742432, 1.00000000,
	0.70395153, 0.80645469, 1.00000000,
	0.70257327, 0.80550180, 1.00000000,
	0.70121928, 0.80456522, 1.00000000,
	0.69988894, 0.80364455, 1.00000000,
	0.69858167, 0.80273941, 1.00000000,
	0.69729688, 0.80184943, 1.00000000,
	0.69603402, 0.80097423, 1.00000000,
	0.69479255, 0.80011347, 1.00000000,
	0.69357196, 0.79926681, 1.00000000,
	0.69237173, 0.79843391, 1.00000000,
	0.69119138, 0.79761446, 1.00000000, /* 15000K */
	0.69003044, 0.79680814, 1.00000000,
	0.68888844, 0.79601466, 1.00000000,
	0.68776494, 0.79523371, 1.00000000,
	0.68665951, 0.79446502, 1.00000000,
	0.68557173, 0.79370830, 1.00000000,
	0.68450119, 0.79296330, 1.00000000,
	0.68344751, 0.79222975, 1.00000000,
	0.68241029, 0.79150740, 1.00000000,
	0.68138918, 0.79079600, 1.00000000,
	0.68038380, 0.79009531, 1.00000000,
	0.67939381, 0.78940511, 1.00000000,
	0.67841888, 0.78872517, 1.00000000,
	0.67745866, 0.78805526, 1.00000000,
	0.67651284, 0.78739518, 1.00000000,
	0.67558112, 0.78674472, 1.00000000,
	0.67466317, 0.78610368, 1.00000000,
	0.67375872, 0.78547186, 1.00000000,
	0.67286748, 0.78484907, 1.00000000,
	0.67198916, 0.78423512, 1.00000000,
	0.67112350, 0.78362984, 1.00000000,
	0.67027024, 0.78303305, 1.00000000,
	0.66942911, 0.78244457, 1.00000000,
	0.66859988, 0.78186425, 1.00000000,
	0.66778228, 0.78129191, 1.00000000,
	0.66697610, 0.78072740, 1.00000000,
	0.66618110, 0.78017057, 1.00000000,
	0.66539706, 0.77962127, 1.00000000,
	0.66462376, 0.77907934, 1.00000000,
	0.66386098, 0.77854465, 1.00000000,
	0.66310852, 0.77801705, 1.00000000,
	0.66236618, 0.77749642, 1.00000000,
	0.66163375, 0.77698261, 1.00000000,
	0.66091106, 0.77647551, 1.00000000,
	0.66019791, 0.77597498, 1.00000000,
	0.65949412, 0.77548090, 1.00000000,
	0.65879952, 0.77499315, 1.00000000,
	0.65811392, 0.77451161, 1.00000000,
	0.65743716, 0.77403618, 1.00000000,
	0.65676908, 0.77356673, 1.00000000,
	0.65610952, 0.77310316, 1.00000000,
	0.65545831, 0.77264537, 1.00000000,
	0.65481530, 0.77219324, 1.00000000,
	0.65418036, 0.77174669, 1.00000000,
	0.65355332, 0.77130560, 1.00000000,
	0.65293404, 0.77086988, 1.00000000,
	0.65232240, 0.77043944, 1.00000000,
	0.65171824, 0.77001419, 1.00000000,
	0.65112144, 0.76959404, 1.00000000,
	0.65053187, 0.76917889, 1.00000000,
	0.64994941, 0.76876866, 1.00000000, /* 20000K */
	0.64937392, 0.76836326, 1.00000000,
	0.64880528, 0.76796263, 1.00000000,
	0.64824339, 0.76756666, 1.00000000,
	0.64768812, 0.76717529, 1.00000000,
	0.64713935, 0.76678844, 1.00000000,
	0.64659699, 0.76640603, 1.00000000,
	0.64606092, 0.76602798, 1.00000000,
	0.64553103, 0.76565424, 1.00000000,
	0.64500722, 0.76528472, 1.00000000,
	0.64448939, 0.76491935, 1.00000000,
	0.64397745, 0.76455808, 1.00000000,
	0.64347129, 0.76420082, 1.00000000,
	0.64297081, 0.76384753, 1.00000000,
	0.64247594, 0.76349813, 1.00000000,
	0.64198657, 0.76315256, 1.00000000,
	0.64150261, 0.76281076, 1.00000000,
	0.64102399, 0.76247267, 1.00000000,
	0.64055061, 0.76213824, 1.00000000,
	0.64008239, 0.76180740, 1.00000000,
	0.63961926, 0.76148010, 1.00000000,
	0.63916112, 0.76115628, 1.00000000,
	0.63870790, 0.76083590, 1.00000000,
	0.63825953, 0.76051890, 1.00000000,
	0.63781592, 0.76020522, 1.00000000,
	0.63737701, 0.75989482, 1.00000000,
	0.63694273, 0.75958764, 1.00000000,
	0.63651299, 0.75928365, 1.00000000,
	0.63608774, 0.75898278, 1.00000000,
	0.63566691, 0.75868499, 1.00000000,
	0.63525042, 0.75839025, 1.00000000,
	0.63483822, 0.75809849, 1.00000000,
	0.63443023, 0.75780969, 1.00000000,
	0.63402641, 0.75752379, 1.00000000,
	0.63362667, 0.75724075, 1.00000000,
	0.63323097, 0.75696053, 1.00000000,
	0.63283925, 0.75668310, 1.00000000,
	0.63245144, 0.75640840, 1.00000000,
	0.63206749, 0.75613641, 1.00000000,
	0.63168735, 0.75586707, 1.00000000,
	0.63131096, 0.75560036, 1.00000000,
	0.63093826, 0.75533624, 1.00000000,
	0.63056920, 0.75507467, 1.00000000,
	0.63020374, 0.75481562, 1.00000000,
	0.62984181, 0.75455904, 1.00000000,
	0.62948337, 0.75430491, 1.00000000,
	0.62912838, 0.75405319, 1.00000000,
	0.62877678, 0.75380385, 1.00000000,
	0.62842852, 0.75355685, 1.00000000,
	0.62808356, 0.75331217, 1.00000000,
	0.62774186, 0.75306977, 1.00000000, /* 25000K */
	0.62740336, 0.75282962, 1.00000000 /* 25100K */
	};

Example see https://github.com/X11-good-tools/xsct .