Rev 1987 | Blame | Compare with Previous | Last modification | View Log | RSS feed
/*
Copyright (c) 2004-2006, The Dojo Foundation
All Rights Reserved.
Licensed under the Academic Free License version 2.1 or above OR the
modified BSD license. For more information on Dojo licensing, see:
http://dojotoolkit.org/community/licensing.shtml
*/
dojo.provide("dojo.gfx.color.hsl");
dojo.require("dojo.lang.array");
dojo.lang.extend(dojo.gfx.color.Color, {toHsl:function () {
return dojo.gfx.color.rgb2hsl(this.toRgb());
}});
dojo.gfx.color.rgb2hsl = function (r, g, b) {
if (dojo.lang.isArray(r)) {
b = r[2] || 0;
g = r[1] || 0;
r = r[0] || 0;
}
r /= 255;
g /= 255;
b /= 255;
var h = null;
var s = null;
var l = null;
var min = Math.min(r, g, b);
var max = Math.max(r, g, b);
var delta = max - min;
l = (min + max) / 2;
s = 0;
if ((l > 0) && (l < 1)) {
s = delta / ((l < 0.5) ? (2 * l) : (2 - 2 * l));
}
h = 0;
if (delta > 0) {
if ((max == r) && (max != g)) {
h += (g - b) / delta;
}
if ((max == g) && (max != b)) {
h += (2 + (b - r) / delta);
}
if ((max == b) && (max != r)) {
h += (4 + (r - g) / delta);
}
h *= 60;
}
h = (h == 0) ? 360 : Math.ceil((h / 360) * 255);
s = Math.ceil(s * 255);
l = Math.ceil(l * 255);
return [h, s, l];
};
dojo.gfx.color.hsl2rgb = function (h, s, l) {
if (dojo.lang.isArray(h)) {
l = h[2] || 0;
s = h[1] || 0;
h = h[0] || 0;
}
h = (h / 255) * 360;
if (h == 360) {
h = 0;
}
s = s / 255;
l = l / 255;
while (h < 0) {
h += 360;
}
while (h > 360) {
h -= 360;
}
var r, g, b;
if (h < 120) {
r = (120 - h) / 60;
g = h / 60;
b = 0;
} else {
if (h < 240) {
r = 0;
g = (240 - h) / 60;
b = (h - 120) / 60;
} else {
r = (h - 240) / 60;
g = 0;
b = (360 - h) / 60;
}
}
r = Math.min(r, 1);
g = Math.min(g, 1);
b = Math.min(b, 1);
r = 2 * s * r + (1 - s);
g = 2 * s * g + (1 - s);
b = 2 * s * b + (1 - s);
if (l < 0.5) {
r = l * r;
g = l * g;
b = l * b;
} else {
r = (1 - l) * r + 2 * l - 1;
g = (1 - l) * g + 2 * l - 1;
b = (1 - l) * b + 2 * l - 1;
}
r = Math.ceil(r * 255);
g = Math.ceil(g * 255);
b = Math.ceil(b * 255);
return [r, g, b];
};
dojo.gfx.color.hsl2hex = function (h, s, l) {
var rgb = dojo.gfx.color.hsl2rgb(h, s, l);
return dojo.gfx.color.rgb2hex(rgb[0], rgb[1], rgb[2]);
};
dojo.gfx.color.hex2hsl = function (hex) {
var rgb = dojo.gfx.color.hex2rgb(hex);
return dojo.gfx.color.rgb2hsl(rgb[0], rgb[1], rgb[2]);
};