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Diffstat (limited to 'docs/js/cielab.js')
| -rw-r--r-- | docs/js/cielab.js | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/docs/js/cielab.js b/docs/js/cielab.js new file mode 100644 index 0000000..2293f0d --- /dev/null +++ b/docs/js/cielab.js @@ -0,0 +1,70 @@ +var cielab = (function(){ + var cielab = {} + + var xyz = [0,0,0] + var rgb = [0,0,0] + + L_range = [0, 100] + a_range = [-86.185, 98.254] + b_range = [-107.863, 94.482] + + cielab.gradient = function (n) { + n = n || 100 + var k = 0 + + var L, a, b + + var L0 = randrange(L_range[0] + 50, L_range[1]) + var L1 = randrange(L_range[0]+ 50, L_range[1]) + var a0 = randrange(a_range[0], a_range[1]) + var a1 = randrange(a_range[0], a_range[1]) + var b0 = randrange(b_range[0], b_range[1]) + var b1 = randrange(b_range[0], b_range[1]) + return function next (aa){ + L = mix(k/n, L0, L1) + a = mix(k/n, a0, a1) + b = mix(k/n, b0, b1) + rgb = xyz2rgb(hunterlab2xyz(L, a, b)) + k += 1 + return rgba_string(rgb, aa) + } + } + function rgba_string (rgb, a) { return "rgb(" + rgb.map(Math.round).join(",") + "," + a + ")" } + function hex_string (rgb) { return "#" + rgb.map(Math.round).map(function(n){ var s = n.toString(16); return s.length == 1 ? "0"+s : s }).join("") } + + function mix(n,a,b){ return n*a + (1-n)*b } + function clamp(n,a,b){ return n<a?a:n<b?n:b } + function hunterlab2xyz (L,a,b) { + var_Y = L / 10 + var_X = a / 17.5 * L / 10 + var_Z = b / 7 * L / 10 + + Y = Math.pow(var_Y, 2) + X = ( var_X + Y ) / 1.02 + Z = -( var_Z - Y ) / 0.847 + xyz = [X,Y,Z] + } + function xyz2rgb(){ + var var_X = xyz[0] / 100 //X from 0 to 95.047 (Observer = 2°, Illuminant = D65) + var var_Y = xyz[1] / 100 //Y from 0 to 100.000 + var var_Z = xyz[2] / 100 //Z from 0 to 108.883 + + var_R = var_X * 3.2406 + var_Y * -1.5372 + var_Z * -0.4986 + var_G = var_X * -0.9689 + var_Y * 1.8758 + var_Z * 0.0415 + var_B = var_X * 0.0557 + var_Y * -0.2040 + var_Z * 1.0570 + + if ( var_R > 0.0031308 ) var_R = 1.055 * Math.pow( var_R, 1 / 2.4 ) - 0.055 + else var_R = 12.92 * var_R + if ( var_G > 0.0031308 ) var_G = 1.055 * Math.pow( var_G, 1 / 2.4 ) - 0.055 + else var_G = 12.92 * var_G + if ( var_B > 0.0031308 ) var_B = 1.055 * Math.pow( var_B, 1 / 2.4 ) - 0.055 + else var_B = 12.92 * var_B + + rgb[0] = clamp(var_R * 255, 0, 255) + rgb[1] = clamp(var_G * 255, 0, 255) + rgb[2] = clamp(var_B * 255, 0, 255) + return rgb + } + + return cielab +})()
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