Files
less.js/lib/less/functions/color.js
2014-10-19 16:57:22 +01:00

278 lines
7.9 KiB
JavaScript

var Dimension = require("../tree/dimension"),
Color = require("../tree/color"),
Quoted = require("../tree/quoted"),
Anonymous = require("../tree/anonymous"),
functionRegistry = require("./function-registry"),
colorFunctions;
function clamp(val) {
return Math.min(1, Math.max(0, val));
}
function hsla(color) {
return colorFunctions.hsla(color.h, color.s, color.l, color.a);
}
function number(n) {
if (n instanceof Dimension) {
return parseFloat(n.unit.is('%') ? n.value / 100 : n.value);
} else if (typeof(n) === 'number') {
return n;
} else {
throw {
type: "Argument",
message: "color functions take numbers as parameters"
};
}
}
function scaled(n, size) {
if (n instanceof Dimension && n.unit.is('%')) {
return parseFloat(n.value * size / 100);
} else {
return number(n);
}
}
colorFunctions = {
rgb: function (r, g, b) {
return colorFunctions.rgba(r, g, b, 1.0);
},
rgba: function (r, g, b, a) {
var rgb = [r, g, b].map(function (c) { return scaled(c, 255); });
a = number(a);
return new Color(rgb, a);
},
hsl: function (h, s, l) {
return colorFunctions.hsla(h, s, l, 1.0);
},
hsla: function (h, s, l, a) {
function hue(h) {
h = h < 0 ? h + 1 : (h > 1 ? h - 1 : h);
if (h * 6 < 1) { return m1 + (m2 - m1) * h * 6; }
else if (h * 2 < 1) { return m2; }
else if (h * 3 < 2) { return m1 + (m2 - m1) * (2/3 - h) * 6; }
else { return m1; }
}
h = (number(h) % 360) / 360;
s = clamp(number(s)); l = clamp(number(l)); a = clamp(number(a));
var m2 = l <= 0.5 ? l * (s + 1) : l + s - l * s;
var m1 = l * 2 - m2;
return colorFunctions.rgba(hue(h + 1/3) * 255,
hue(h) * 255,
hue(h - 1/3) * 255,
a);
},
hsv: function(h, s, v) {
return colorFunctions.hsva(h, s, v, 1.0);
},
hsva: function(h, s, v, a) {
h = ((number(h) % 360) / 360) * 360;
s = number(s); v = number(v); a = number(a);
var i, f;
i = Math.floor((h / 60) % 6);
f = (h / 60) - i;
var vs = [v,
v * (1 - s),
v * (1 - f * s),
v * (1 - (1 - f) * s)];
var perm = [[0, 3, 1],
[2, 0, 1],
[1, 0, 3],
[1, 2, 0],
[3, 1, 0],
[0, 1, 2]];
return colorFunctions.rgba(vs[perm[i][0]] * 255,
vs[perm[i][1]] * 255,
vs[perm[i][2]] * 255,
a);
},
hue: function (color) {
return new Dimension(color.toHSL().h);
},
saturation: function (color) {
return new Dimension(color.toHSL().s * 100, '%');
},
lightness: function (color) {
return new Dimension(color.toHSL().l * 100, '%');
},
hsvhue: function(color) {
return new Dimension(color.toHSV().h);
},
hsvsaturation: function (color) {
return new Dimension(color.toHSV().s * 100, '%');
},
hsvvalue: function (color) {
return new Dimension(color.toHSV().v * 100, '%');
},
red: function (color) {
return new Dimension(color.rgb[0]);
},
green: function (color) {
return new Dimension(color.rgb[1]);
},
blue: function (color) {
return new Dimension(color.rgb[2]);
},
alpha: function (color) {
return new Dimension(color.toHSL().a);
},
luma: function (color) {
return new Dimension(color.luma() * color.alpha * 100, '%');
},
luminance: function (color) {
var luminance =
(0.2126 * color.rgb[0] / 255)
+ (0.7152 * color.rgb[1] / 255)
+ (0.0722 * color.rgb[2] / 255);
return new Dimension(luminance * color.alpha * 100, '%');
},
saturate: function (color, amount) {
// filter: saturate(3.2);
// should be kept as is, so check for color
if (!color.rgb) {
return null;
}
var hsl = color.toHSL();
hsl.s += amount.value / 100;
hsl.s = clamp(hsl.s);
return hsla(hsl);
},
desaturate: function (color, amount) {
var hsl = color.toHSL();
hsl.s -= amount.value / 100;
hsl.s = clamp(hsl.s);
return hsla(hsl);
},
lighten: function (color, amount) {
var hsl = color.toHSL();
hsl.l += amount.value / 100;
hsl.l = clamp(hsl.l);
return hsla(hsl);
},
darken: function (color, amount) {
var hsl = color.toHSL();
hsl.l -= amount.value / 100;
hsl.l = clamp(hsl.l);
return hsla(hsl);
},
fadein: function (color, amount) {
var hsl = color.toHSL();
hsl.a += amount.value / 100;
hsl.a = clamp(hsl.a);
return hsla(hsl);
},
fadeout: function (color, amount) {
var hsl = color.toHSL();
hsl.a -= amount.value / 100;
hsl.a = clamp(hsl.a);
return hsla(hsl);
},
fade: function (color, amount) {
var hsl = color.toHSL();
hsl.a = amount.value / 100;
hsl.a = clamp(hsl.a);
return hsla(hsl);
},
spin: function (color, amount) {
var hsl = color.toHSL();
var hue = (hsl.h + amount.value) % 360;
hsl.h = hue < 0 ? 360 + hue : hue;
return hsla(hsl);
},
//
// Copyright (c) 2006-2009 Hampton Catlin, Nathan Weizenbaum, and Chris Eppstein
// http://sass-lang.com
//
mix: function (color1, color2, weight) {
if (!weight) {
weight = new Dimension(50);
}
var p = weight.value / 100.0;
var w = p * 2 - 1;
var a = color1.toHSL().a - color2.toHSL().a;
var w1 = (((w * a == -1) ? w : (w + a) / (1 + w * a)) + 1) / 2.0;
var w2 = 1 - w1;
var rgb = [color1.rgb[0] * w1 + color2.rgb[0] * w2,
color1.rgb[1] * w1 + color2.rgb[1] * w2,
color1.rgb[2] * w1 + color2.rgb[2] * w2];
var alpha = color1.alpha * p + color2.alpha * (1 - p);
return new Color(rgb, alpha);
},
greyscale: function (color) {
return colorFunctions.desaturate(color, new Dimension(100));
},
contrast: function (color, dark, light, threshold) {
// filter: contrast(3.2);
// should be kept as is, so check for color
if (!color.rgb) {
return null;
}
if (typeof light === 'undefined') {
light = colorFunctions.rgba(255, 255, 255, 1.0);
}
if (typeof dark === 'undefined') {
dark = colorFunctions.rgba(0, 0, 0, 1.0);
}
//Figure out which is actually light and dark!
if (dark.luma() > light.luma()) {
var t = light;
light = dark;
dark = t;
}
if (typeof threshold === 'undefined') {
threshold = 0.43;
} else {
threshold = number(threshold);
}
if (color.luma() < threshold) {
return light;
} else {
return dark;
}
},
argb: function (color) {
return new Anonymous(color.toARGB());
},
color: function(c) {
if ((c instanceof Quoted) &&
(/^#([a-f0-9]{6}|[a-f0-9]{3})$/i.test(c.value))) {
return new Color(c.value.slice(1));
}
if ((c instanceof Color) || (c = Color.fromKeyword(c.value))) {
c.keyword = undefined;
return c;
}
throw {
type: "Argument",
message: "argument must be a color keyword or 3/6 digit hex e.g. #FFF"
};
},
tint: function(color, amount) {
return colorFunctions.mix(colorFunctions.rgb(255,255,255), color, amount);
},
shade: function(color, amount) {
return colorFunctions.mix(colorFunctions.rgb(0, 0, 0), color, amount);
}
};
functionRegistry.addMultiple(colorFunctions);