git.iko.soy/elk
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elk/core/Native/Color.js
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1function nativeColor(elm) {
2"use strict";
4function extract(c) {
5 if (c._3 === 1) { return 'rgb(' + c._0 + ',' + c._1 + ',' + c._2 + ')'; }
6 return 'rgba(' + c._0 + ',' + c._1 + ',' + c._2 + ',' + c._3 + ')';
7}
8function complement(rgb) {
9 var hsv = toHSV(rgb);
10 hsv.hue = (hsv.hue + 180) % 360;
11 return toRGB(hsv);
14function hsva(h) { return function(s) { return function(v) { return function(a) {
15 var clr = toRGB({hue:h, saturation:s, value:v});
16 clr._3 = a;
17 return clr;
18 }; }; };
21function hsv(h) { return function(s) { return function(v) {
22 return toRGB({hue:h, saturation:s, value:v}); }; }; }
24function toHSV(rgb) {
25 var hsv = {};
26 var r = rgb._0 / 255.0, g = rgb._1 / 255.0, b = rgb._2 / 255.0;
27 var M = Math.max(r,g,b);
28 var m = Math.min(r,g,b);
29 var c = M - m;
31 var h = 0;
32 if (c === 0) { h = 0; }
33 else if (M === r) { h = ((g - b) / c) % 6; }
34 else if (M === g) { h = ((b - r) / c) + 2; }
35 else if (M === b) { h = ((r - g) / c) + 4; }
36 h *= 60;
38 return { value : M, hue : h, saturation : (M === 0 ? 0 : c / M) };
41function between(lo,hi,x) { return lo <= x && x < hi; }
42function norm(n) { return Math.round(n*255); }
44function toRGB(hsv) {
45 var c = hsv.value * hsv.saturation;
46 var hue = hsv.hue / 60;
47 var x = c * (1 - Math.abs((hue % 2) - 1));
48 var r = 0, g = 0, b = 0;
49 if (between(0,1,hue)) { r = c; g = x; b = 0; }
50 else if (between(1,2,hue)) { r = x; g = c; b = 0; }
51 else if (between(2,3,hue)) { r = 0; g = c; b = x; }
52 else if (between(3,4,hue)) { r = 0; g = x; b = c; }
53 else if (between(4,5,hue)) { r = x; g = 0; b = c; }
54 else if (between(5,6,hue)) { r = c; g = 0; b = x; }
56 var m = hsv.value - c;
57 return [ "Color", norm(r+m), norm(g+m), norm(b+m), 1 ];
60elm.Native.Color = {
61 hsva:hsva,
62 hsv:hsv,
63 complement:complement,
64 extract:extract};