File: /home1/bloga741/public_html/likedreams/test/js/colors.js
;(function(window, undefined){
"use strict"
var _valueRanges = {
rgb: {r: [0, 255], g: [0, 255], b: [0, 255]},
hsv: {h: [0, 360], s: [0, 100], v: [0, 100]},
hsl: {h: [0, 360], s: [0, 100], l: [0, 100]},
cmy: {c: [0, 100], m: [0, 100], y: [0, 100]},
cmyk: {c: [0, 100], m: [0, 100], y: [0, 100], k: [0, 100]},
Lab: {L: [0, 100], a: [-128, 127], b: [-128, 127]},
XYZ: {X: [0, 100], Y: [0, 100], Z: [0, 100]},
alpha: {alpha: [0, 1]},
HEX: {HEX: [0, 16777215]} // maybe we don't need this
},
_instance = {},
_colors = {},
// http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html for more
XYZMatrix = { // Observer = 2° (CIE 1931), Illuminant = D65
X: [ 0.4124564, 0.3575761, 0.1804375],
Y: [ 0.2126729, 0.7151522, 0.0721750],
Z: [ 0.0193339, 0.1191920, 0.9503041],
R: [ 3.2404542, -1.5371385, -0.4985314],
G: [-0.9692660, 1.8760108, 0.0415560],
B: [ 0.0556434, -0.2040259, 1.0572252]
},
grey = {r: 0.298954, g: 0.586434, b: 0.114612}, // CIE-XYZ 1931
luminance = {r: 0.2126, g: 0.7152, b: 0.0722}, // W3C 2.0
_math = Math,
_parseint = parseInt,
Colors = window.Colors = function(options) {
this.colors = {RND: {}};
this.options = {
color: 'rgba(204, 82, 37, 0.8)', // init value(s)...
XYZMatrix: XYZMatrix,
// XYZReference: {},
grey: grey,
luminance: luminance,
valueRanges: _valueRanges
// customBG: '#808080'
// convertCallback: undefined,
// allMixDetails: false
};
initInstance(this, options || {});
},
initInstance = function(THIS, options) {
var matrix,
importColor,
_options = THIS.options,
customBG;
focusInstance(THIS);
for (var option in options) {
if (options[option] !== undefined) _options[option] = options[option];
}
matrix = _options.XYZMatrix;
if (!options.XYZReference) _options.XYZReference = {
X: matrix.X[0] + matrix.X[1] + matrix.X[2],
Y: matrix.Y[0] + matrix.Y[1] + matrix.Y[2],
Z: matrix.Z[0] + matrix.Z[1] + matrix.Z[2]
};
customBG = _options.customBG;
_options.customBG = (typeof customBG === 'string') ? ColorConverter.txt2color(customBG).rgb : customBG;
_colors = setColor(THIS.colors, _options.color, undefined, true); // THIS.colors = _colors =
},
focusInstance = function(THIS) {
if (_instance !== THIS) {
_instance = THIS;
_colors = THIS.colors;
}
};
Colors.prototype.setColor = function(newCol, type, alpha) {
focusInstance(this);
if (newCol) {
return setColor(this.colors, newCol, type, undefined, alpha);
} else {
if (alpha !== undefined) {
this.colors.alpha = limitValue(alpha, 0, 1);
}
return convertColors(type);
}
};
Colors.prototype.getColor = function(type) {
var result = this.colors, n = 0;
if (type) {
type = type.split('.');
while (result[type[n]]) {
result = result[type[n++]];
}
if (type.length !== n) {
result = undefined;
}
}
return result;
};
Colors.prototype.setCustomBackground = function(col) { // wild gues,... check again...
focusInstance(this); // needed???
this.options.customBG = (typeof col === 'string') ? ColorConverter.txt2color(col).rgb : col;
// return setColor(this.colors, this.options.customBG, 'rgb', true); // !!!!RGB
return setColor(this.colors, undefined, 'rgb'); // just recalculate existing
};
Colors.prototype.saveAsBackground = function() { // alpha
focusInstance(this); // needed???
// return setColor(this.colors, this.colors.RND.rgb, 'rgb', true);
return setColor(this.colors, undefined, 'rgb', true);
};
Colors.prototype.convertColor = function(color, type) {
var convert = ColorConverter,
ranges = _valueRanges,
types = type.split('2'),
fromType = types[0],
toType = types[1],
test = /(?:RG|HS|CM|LA)/,
normalizeFrom = test.test(fromType),
normalizeTo = test.test(toType),
exceptions = {LAB: 'Lab'},
normalize = function(color, type, reverse) {
var result = {},
Lab = type === 'Lab' ? 1 : 0;
for (var n in color) { // faster (but bigger) way: if/else outside 2 for loops
result[n] = reverse ?
_math.round(color[n] * (Lab || ranges[type][n][1])) :
color[n] / (Lab || ranges[type][n][1]);
}
return result;
};
fromType = ranges[fromType] ? fromType : exceptions[fromType] || fromType.toLowerCase();
toType = ranges[toType] ? toType : exceptions[toType] || toType.toLowerCase();
if (normalizeFrom && type !== 'RGB2HEX') { // from ABC to abc
color = normalize(color, fromType);
}
color = fromType === toType ? color : ( // same type; returns same/normalized version
convert[fromType + '2' + toType] ? convert[fromType + '2' + toType](color, true) : // existing converter
toType === 'HEX' ? convert.RGB2HEX(type === 'RGB2HEX' ? color : normalize(fromType === 'rgb' ? color :
convert[fromType + '2rgb'](color, true), 'rgb', true)) :
convert['rgb2' + toType](convert[fromType + '2rgb'](color, true), true) // not in ColorConverter
);
if (normalizeTo) { // from abc to ABC
color = normalize(color, toType, true);
}
return color;
};
// ------------------------------------------------------ //
// ---------- Color calculation related stuff ---------- //
// -------------------------------------------------------//
function setColor(colors, color, type, save, alpha) { // color only full range
if (typeof color === 'string') {
var color = ColorConverter.txt2color(color); // new object
type = color.type;
_colors[type] = color[type];
alpha = alpha !== undefined ? alpha : color.alpha;
} else if (color) {
for (var n in color) {
colors[type][n] = limitValue(color[n] / _valueRanges[type][n][1], 0 , 1);
}
}
if (alpha !== undefined) {
colors.alpha = limitValue(+alpha, 0, 1);
}
return convertColors(type, save ? colors : undefined);
}
function saveAsBackground(RGB, rgb, alpha) {
var grey = _instance.options.grey,
color = {};
color.RGB = {r: RGB.r, g: RGB.g, b: RGB.b};
color.rgb = {r: rgb.r, g: rgb.g, b: rgb.b};
color.alpha = alpha;
// color.RGBLuminance = getLuminance(RGB);
color.equivalentGrey = _math.round(grey.r * RGB.r + grey.g * RGB.g + grey.b * RGB.b);
color.rgbaMixBlack = mixColors(rgb, {r: 0, g: 0, b: 0}, alpha, 1);
color.rgbaMixWhite = mixColors(rgb, {r: 1, g: 1, b: 1}, alpha, 1);
color.rgbaMixBlack.luminance = getLuminance(color.rgbaMixBlack, true);
color.rgbaMixWhite.luminance = getLuminance(color.rgbaMixWhite, true);
if (_instance.options.customBG) {
color.rgbaMixCustom = mixColors(rgb, _instance.options.customBG, alpha, 1);
color.rgbaMixCustom.luminance = getLuminance(color.rgbaMixCustom, true);
_instance.options.customBG.luminance = getLuminance(_instance.options.customBG, true);
}
return color;
}
function convertColors(type, colorObj) {
// console.time('convertColors');
var _Math = _math,
colors = colorObj || _colors,
convert = ColorConverter,
options = _instance.options,
ranges = _valueRanges,
RND = colors.RND,
// type = colorType, // || _mode.type,
modes, mode = '', from = '', // value = '',
exceptions = {hsl: 'hsv', cmyk: 'cmy', rgb: type},
RGB = RND.rgb, SAVE, SMART;
if (type !== 'alpha') {
for (var typ in ranges) {
if (!ranges[typ][typ]) { // no alpha|HEX
if (type !== typ && typ !== 'XYZ') {
from = exceptions[typ] || 'rgb';
colors[typ] = convert[from + '2' + typ](colors[from]);
}
if (!RND[typ]) RND[typ] = {};
modes = colors[typ];
for(mode in modes) {
RND[typ][mode] = _Math.round(modes[mode] * (typ === 'Lab' ? 1 : ranges[typ][mode][1]));
}
}
}
if (type !== 'Lab') {
delete colors._rgb;
}
RGB = RND.rgb;
colors.HEX = convert.RGB2HEX(RGB);
colors.equivalentGrey =
options.grey.r * colors.rgb.r +
options.grey.g * colors.rgb.g +
options.grey.b * colors.rgb.b;
colors.webSave = SAVE = getClosestWebColor(RGB, 51);
// colors.webSave.HEX = convert.RGB2HEX(colors.webSave);
colors.webSmart = SMART = getClosestWebColor(RGB, 17);
// colors.webSmart.HEX = convert.RGB2HEX(colors.webSmart);
colors.saveColor =
RGB.r === SAVE.r && RGB.g === SAVE.g && RGB.b === SAVE.b ? 'web save' :
RGB.r === SMART.r && RGB.g === SMART.g && RGB.b === SMART.b ? 'web smart' : '';
colors.hueRGB = convert.hue2RGB(colors.hsv.h);
if (colorObj) {
colors.background = saveAsBackground(RGB, colors.rgb, colors.alpha);
}
} // else RGB = RND.rgb;
var rgb = colors.rgb, // for better minification...
alpha = colors.alpha,
luminance = 'luminance',
background = colors.background,
rgbaMixBlack, rgbaMixWhite, rgbaMixCustom,
rgbaMixBG, rgbaMixBGMixBlack, rgbaMixBGMixWhite, rgbaMixBGMixCustom,
_mixColors = mixColors,
_getLuminance = getLuminance,
_getWCAG2Ratio = getWCAG2Ratio,
_getHueDelta = getHueDelta;
rgbaMixBlack = _mixColors(rgb, {r: 0, g: 0, b: 0}, alpha, 1);
rgbaMixBlack[luminance] = _getLuminance(rgbaMixBlack, true);
colors.rgbaMixBlack = rgbaMixBlack;
rgbaMixWhite = _mixColors(rgb, {r: 1, g: 1, b: 1}, alpha, 1);
rgbaMixWhite[luminance] = _getLuminance(rgbaMixWhite, true);
colors.rgbaMixWhite = rgbaMixWhite;
if (options.allMixDetails) {
rgbaMixBlack.WCAG2Ratio = _getWCAG2Ratio(rgbaMixBlack[luminance], 0);
rgbaMixWhite.WCAG2Ratio = _getWCAG2Ratio(rgbaMixWhite[luminance], 1);
if (options.customBG) {
rgbaMixCustom = _mixColors(rgb, options.customBG, alpha, 1);
rgbaMixCustom[luminance] = _getLuminance(rgbaMixCustom, true);
rgbaMixCustom.WCAG2Ratio = _getWCAG2Ratio(rgbaMixCustom[luminance], options.customBG[luminance]);
colors.rgbaMixCustom = rgbaMixCustom;
}
rgbaMixBG = _mixColors(rgb, background.rgb, alpha, background.alpha);
rgbaMixBG[luminance] = _getLuminance(rgbaMixBG, true); // ?? do we need this?
colors.rgbaMixBG = rgbaMixBG;
rgbaMixBGMixBlack = _mixColors(rgb, background.rgbaMixBlack, alpha, 1);
rgbaMixBGMixBlack[luminance] = _getLuminance(rgbaMixBGMixBlack, true);
rgbaMixBGMixBlack.WCAG2Ratio = _getWCAG2Ratio(rgbaMixBGMixBlack[luminance],
background.rgbaMixBlack[luminance]);
/* ------ */
rgbaMixBGMixBlack.luminanceDelta = _Math.abs(
rgbaMixBGMixBlack[luminance] - background.rgbaMixBlack[luminance]);
rgbaMixBGMixBlack.hueDelta = _getHueDelta(background.rgbaMixBlack, rgbaMixBGMixBlack, true);
/* ------ */
colors.rgbaMixBGMixBlack = rgbaMixBGMixBlack;
rgbaMixBGMixWhite = _mixColors(rgb, background.rgbaMixWhite, alpha, 1);
rgbaMixBGMixWhite[luminance] = _getLuminance(rgbaMixBGMixWhite, true);
rgbaMixBGMixWhite.WCAG2Ratio = _getWCAG2Ratio(rgbaMixBGMixWhite[luminance],
background.rgbaMixWhite[luminance]);
/* ------ */
rgbaMixBGMixWhite.luminanceDelta = _Math.abs(
rgbaMixBGMixWhite[luminance] - background.rgbaMixWhite[luminance]);
rgbaMixBGMixWhite.hueDelta = _getHueDelta(background.rgbaMixWhite, rgbaMixBGMixWhite, true);
/* ------ */
colors.rgbaMixBGMixWhite = rgbaMixBGMixWhite;
}
if (options.customBG) {
rgbaMixBGMixCustom = _mixColors(rgb, background.rgbaMixCustom, alpha, 1);
rgbaMixBGMixCustom[luminance] = _getLuminance(rgbaMixBGMixCustom, true);
rgbaMixBGMixCustom.WCAG2Ratio = _getWCAG2Ratio(rgbaMixBGMixCustom[luminance],
background.rgbaMixCustom[luminance]);
colors.rgbaMixBGMixCustom = rgbaMixBGMixCustom;
/* ------ */
rgbaMixBGMixCustom.luminanceDelta = _Math.abs(
rgbaMixBGMixCustom[luminance] - background.rgbaMixCustom[luminance]);
rgbaMixBGMixCustom.hueDelta = _getHueDelta(background.rgbaMixCustom, rgbaMixBGMixCustom, true);
/* ------ */
}
colors.RGBLuminance = _getLuminance(RGB);
colors.HUELuminance = _getLuminance(colors.hueRGB);
// renderVars.readyToRender = true;
if (options.convertCallback) {
options.convertCallback(colors, type); //, convert); //, _mode);
}
// console.timeEnd('convertColors')
// if (colorObj)
return colors;
}
// ------------------------------------------------------ //
// ------------------ color conversion ------------------ //
// -------------------------------------------------------//
var ColorConverter = {
txt2color: function(txt) {
var color = {},
parts = txt.replace(/(?:#|\)|%)/g, '').split('('),
values = (parts[1] || '').split(/,\s*/),
type = parts[1] ? parts[0].substr(0, 3) : 'rgb',
m = '';
color.type = type;
color[type] = {};
if (parts[1]) {
for (var n = 3; n--; ) {
m = type[n] || type.charAt(n); // IE7
color[type][m] = +values[n] / _valueRanges[type][m][1];
}
} else {
color.rgb = ColorConverter.HEX2rgb(parts[0]);
}
// color.color = color[type];
color.alpha = values[3] ? +values[3] : 1;
return color;
},
RGB2HEX: function(RGB) {
return (
(RGB.r < 16 ? '0' : '') + RGB.r.toString(16) +
(RGB.g < 16 ? '0' : '') + RGB.g.toString(16) +
(RGB.b < 16 ? '0' : '') + RGB.b.toString(16)
).toUpperCase();
},
HEX2rgb: function(HEX) {
var _parseInt = _parseint;
HEX = HEX.split(''); // IE7
return {
r: _parseInt(HEX[0] + HEX[HEX[3] ? 1 : 0], 16) / 255,
g: _parseInt(HEX[HEX[3] ? 2 : 1] + (HEX[3] || HEX[1]), 16) / 255,
b: _parseInt((HEX[4] || HEX[2]) + (HEX[5] || HEX[2]), 16) / 255
};
},
hue2RGB: function(hue) {
var _Math = _math,
h = hue * 6,
mod = ~~h % 6, // Math.floor(h) -> faster in most browsers
i = h === 6 ? 0 : (h - mod);
return {
r: _Math.round([1, 1 - i, 0, 0, i, 1][mod] * 255),
g: _Math.round([i, 1, 1, 1 - i, 0, 0][mod] * 255),
b: _Math.round([0, 0, i, 1, 1, 1 - i][mod] * 255)
};
},
// ------------------------ HSV ------------------------ //
rgb2hsv: function(rgb) { // faster
var _Math = _math,
r = rgb.r,
g = rgb.g,
b = rgb.b,
k = 0, chroma, min, s;
if (g < b) {
g = b + (b = g, 0);
k = -1;
}
min = b;
if (r < g) {
r = g + (g = r, 0);
k = -2 / 6 - k;
min = _Math.min(g, b); // g < b ? g : b; ???
}
chroma = r - min;
s = r ? (chroma / r) : 0;
return {
h: s < 1e-15 ? ((_colors && _colors.hsl && _colors.hsl.h) || 0) :
chroma ? _Math.abs(k + (g - b) / (6 * chroma)) : 0,
s: r ? (chroma / r) : ((_colors && _colors.hsv && _colors.hsv.s) || 0), // ??_colors.hsv.s || 0
v: r
};
},
hsv2rgb: function(hsv) {
var h = hsv.h * 6,
s = hsv.s,
v = hsv.v,
i = ~~h, // Math.floor(h) -> faster in most browsers
f = h - i,
p = v * (1 - s),
q = v * (1 - f * s),
t = v * (1 - (1 - f) * s),
mod = i % 6;
return {
r: [v, q, p, p, t, v][mod],
g: [t, v, v, q, p, p][mod],
b: [p, p, t, v, v, q][mod]
};
},
// ------------------------ HSL ------------------------ //
hsv2hsl: function(hsv) {
var l = (2 - hsv.s) * hsv.v,
s = hsv.s * hsv.v;
s = !hsv.s ? 0 : l < 1 ? (l ? s / l : 0) : s / (2 - l);
return {
h: hsv.h,
s: !hsv.v && !s ? ((_colors && _colors.hsl && _colors.hsl.s) || 0) : s, // ???
l: l / 2
};
},
rgb2hsl: function(rgb, dependent) { // not used in Color
var hsv = ColorConverter.rgb2hsv(rgb);
return ColorConverter.hsv2hsl(dependent ? hsv : (_colors.hsv = hsv));
},
hsl2rgb: function(hsl) {
var h = hsl.h * 6,
s = hsl.s,
l = hsl.l,
v = l < 0.5 ? l * (1 + s) : (l + s) - (s * l),
m = l + l - v,
sv = v ? ((v - m) / v) : 0,
sextant = ~~h, // Math.floor(h) -> faster in most browsers
fract = h - sextant,
vsf = v * sv * fract,
t = m + vsf,
q = v - vsf,
mod = sextant % 6;
return {
r: [v, q, m, m, t, v][mod],
g: [t, v, v, q, m, m][mod],
b: [m, m, t, v, v, q][mod]
};
},
// ------------------------ CMYK ------------------------ //
// Quote from Wikipedia:
// "Since RGB and CMYK spaces are both device-dependent spaces, there is no
// simple or general conversion formula that converts between them.
// Conversions are generally done through color management systems, using
// color profiles that describe the spaces being converted. Nevertheless, the
// conversions cannot be exact, since these spaces have very different gamuts."
// Translation: the following are just simple RGB to CMY(K) and visa versa conversion functions.
rgb2cmy: function(rgb) {
return {
c: 1 - rgb.r,
m: 1 - rgb.g,
y: 1 - rgb.b
};
},
cmy2cmyk: function(cmy) {
var _Math = _math,
k = _Math.min(_Math.min(cmy.c, cmy.m), cmy.y),
t = 1 - k || 1e-20;
return { // regular
c: (cmy.c - k) / t,
m: (cmy.m - k) / t,
y: (cmy.y - k) / t,
k: k
};
},
cmyk2cmy: function(cmyk) {
var k = cmyk.k;
return { // regular
c: cmyk.c * (1 - k) + k,
m: cmyk.m * (1 - k) + k,
y: cmyk.y * (1 - k) + k
};
},
cmy2rgb: function(cmy) {
return {
r: 1 - cmy.c,
g: 1 - cmy.m,
b: 1 - cmy.y
};
},
rgb2cmyk: function(rgb, dependent) {
var cmy = ColorConverter.rgb2cmy(rgb); // doppelt??
return ColorConverter.cmy2cmyk(dependent ? cmy : (_colors.cmy = cmy));
},
cmyk2rgb: function(cmyk, dependent) {
var cmy = ColorConverter.cmyk2cmy(cmyk); // doppelt??
return ColorConverter.cmy2rgb(dependent ? cmy : (_colors.cmy = cmy));
},
// ------------------------ LAB ------------------------ //
XYZ2rgb: function(XYZ, skip) {
var _Math = _math,
M = _instance.options.XYZMatrix,
X = XYZ.X,
Y = XYZ.Y,
Z = XYZ.Z,
r = X * M.R[0] + Y * M.R[1] + Z * M.R[2],
g = X * M.G[0] + Y * M.G[1] + Z * M.G[2],
b = X * M.B[0] + Y * M.B[1] + Z * M.B[2],
N = 1 / 2.4;
M = 0.0031308;
r = (r > M ? 1.055 * _Math.pow(r, N) - 0.055 : 12.92 * r);
g = (g > M ? 1.055 * _Math.pow(g, N) - 0.055 : 12.92 * g);
b = (b > M ? 1.055 * _Math.pow(b, N) - 0.055 : 12.92 * b);
if (!skip) { // out of gammut
_colors._rgb = {r: r, g: g, b: b};
}
return {
r: limitValue(r, 0, 1),
g: limitValue(g, 0, 1),
b: limitValue(b, 0, 1)
};
},
rgb2XYZ: function(rgb) {
var _Math = _math,
M = _instance.options.XYZMatrix,
r = rgb.r,
g = rgb.g,
b = rgb.b,
N = 0.04045;
r = (r > N ? _Math.pow((r + 0.055) / 1.055, 2.4) : r / 12.92);
g = (g > N ? _Math.pow((g + 0.055) / 1.055, 2.4) : g / 12.92);
b = (b > N ? _Math.pow((b + 0.055) / 1.055, 2.4) : b / 12.92);
return {
X: r * M.X[0] + g * M.X[1] + b * M.X[2],
Y: r * M.Y[0] + g * M.Y[1] + b * M.Y[2],
Z: r * M.Z[0] + g * M.Z[1] + b * M.Z[2]
};
},
XYZ2Lab: function(XYZ) {
var _Math = _math,
R = _instance.options.XYZReference,
X = XYZ.X / R.X,
Y = XYZ.Y / R.Y,
Z = XYZ.Z / R.Z,
N = 16 / 116, M = 1 / 3, K = 0.008856, L = 7.787037;
X = X > K ? _Math.pow(X, M) : (L * X) + N;
Y = Y > K ? _Math.pow(Y, M) : (L * Y) + N;
Z = Z > K ? _Math.pow(Z, M) : (L * Z) + N;
return {
L: (116 * Y) - 16,
a: 500 * (X - Y),
b: 200 * (Y - Z)
};
},
Lab2XYZ: function(Lab) {
var _Math = _math,
R = _instance.options.XYZReference,
Y = (Lab.L + 16) / 116,
X = Lab.a / 500 + Y,
Z = Y - Lab.b / 200,
X3 = _Math.pow(X, 3),
Y3 = _Math.pow(Y, 3),
Z3 = _Math.pow(Z, 3),
N = 16 / 116, K = 0.008856, L = 7.787037;
return {
X: (X3 > K ? X3 : (X - N) / L) * R.X,
Y: (Y3 > K ? Y3 : (Y - N) / L) * R.Y,
Z: (Z3 > K ? Z3 : (Z - N) / L) * R.Z
};
},
rgb2Lab: function(rgb, dependent) {
var XYZ = ColorConverter.rgb2XYZ(rgb);
return ColorConverter.XYZ2Lab(dependent ? XYZ : (_colors.XYZ = XYZ));
},
Lab2rgb: function(Lab, dependent) {
var XYZ = ColorConverter.Lab2XYZ(Lab);
return ColorConverter.XYZ2rgb(dependent ? XYZ : (_colors.XYZ = XYZ), dependent);
}
};
// ------------------------------------------------------ //
// ------------------ helper functions ------------------ //
// -------------------------------------------------------//
function getClosestWebColor(RGB, val) {
var out = {},
tmp = 0,
half = val / 2;
for (var n in RGB) {
tmp = RGB[n] % val; // 51 = 'web save', 17 = 'web smart'
out[n] = RGB[n] + (tmp > half ? val - tmp : -tmp);
}
return out;
}
function getHueDelta(rgb1, rgb2, nominal) {
var _Math = _math;
return (_Math.max(rgb1.r - rgb2.r, rgb2.r - rgb1.r) +
_Math.max(rgb1.g - rgb2.g, rgb2.g - rgb1.g) +
_Math.max(rgb1.b - rgb2.b, rgb2.b - rgb1.b)) * (nominal ? 255 : 1) / 765;
}
function getLuminance(rgb, normalized) {
var div = normalized ? 1 : 255,
RGB = [rgb.r / div, rgb.g / div, rgb.b / div],
luminance = _instance.options.luminance;
for (var i = RGB.length; i--; ) {
RGB[i] = RGB[i] <= 0.03928 ? RGB[i] / 12.92 : _math.pow(((RGB[i] + 0.055) / 1.055), 2.4);
}
return ((luminance.r * RGB[0]) + (luminance.g * RGB[1]) + (luminance.b * RGB[2]));
}
function mixColors(topColor, bottomColor, topAlpha, bottomAlpha) {
var newColor = {},
alphaTop = (topAlpha !== undefined ? topAlpha : 1),
alphaBottom = (bottomAlpha !== undefined ? bottomAlpha : 1),
alpha = alphaTop + alphaBottom * (1 - alphaTop); // 1 - (1 - alphaTop) * (1 - alphaBottom);
for(var n in topColor) {
newColor[n] = (topColor[n] * alphaTop + bottomColor[n] * alphaBottom * (1 - alphaTop)) / alpha;
}
newColor.a = alpha;
return newColor;
}
function getWCAG2Ratio(lum1, lum2) {
var ratio = 1;
if (lum1 >= lum2) {
ratio = (lum1 + 0.05) / (lum2 + 0.05);
} else {
ratio = (lum2 + 0.05) / (lum1 + 0.05);
}
return _math.round(ratio * 100) / 100;
}
function limitValue(value, min, max) {
// return Math.max(min, Math.min(max, value)); // faster??
return (value > max ? max : value < min ? min : value);
}
})(window);