/**
* @class Ext.draw.Color
* @extends Object
*
* Represents an RGB color and provides helper functions get
* color components in HSL color space.
*/
Ext.define('Ext.draw.Color', {
/* Begin Definitions */
/* End Definitions */
colorToHexRe: /(.*?)rgb\((\d+),\s*(\d+),\s*(\d+)\)/,
rgbRe: /\s*rgb\s*\(\s*([0-9]+)\s*,\s*([0-9]+)\s*,\s*([0-9]+)\s*\)\s*/,
hexRe: /\s*#([0-9a-fA-F][0-9a-fA-F]?)([0-9a-fA-F][0-9a-fA-F]?)([0-9a-fA-F][0-9a-fA-F]?)\s*/,
/**
* @cfg {Number} lightnessFactor
*
* The default factor to compute the lighter or darker color. Defaults to 0.2.
*/
lightnessFactor: 0.2,
/**
* @constructor
* @param {Number} red Red component (0..255)
* @param {Number} green Green component (0..255)
* @param {Number} blue Blue component (0..255)
*/
constructor : function(red, green, blue) {
var me = this,
clamp = Ext.Number.constrain;
me.r = clamp(red, 0, 255);
me.g = clamp(green, 0, 255);
me.b = clamp(blue, 0, 255);
},
/**
* Get the red component of the color, in the range 0..255.
* @return {Number}
*/
getRed: function() {
return this.r;
},
/**
* Get the green component of the color, in the range 0..255.
* @return {Number}
*/
getGreen: function() {
return this.g;
},
/**
* Get the blue component of the color, in the range 0..255.
* @return {Number}
*/
getBlue: function() {
return this.b;
},
/**
* Get the RGB values.
* @return {Array}
*/
getRGB: function() {
var me = this;
return [me.r, me.g, me.b];
},
/**
* Get the equivalent HSL components of the color.
* @return {Array}
*/
getHSL: function() {
var me = this,
r = me.r / 255,
g = me.g / 255,
b = me.b / 255,
max = Math.max(r, g, b),
min = Math.min(r, g, b),
delta = max - min,
h,
s = 0,
l = 0.5 * (max + min);
// min==max means achromatic (hue is undefined)
if (min != max) {
s = (l < 0.5) ? delta / (max + min) : delta / (2 - max - min);
if (r == max) {
h = 60 * (g - b) / delta;
} else if (g == max) {
h = 120 + 60 * (b - r) / delta;
} else {
h = 240 + 60 * (r - g) / delta;
}
if (h < 0) {
h += 360;
}
if (h >= 360) {
h -= 360;
}
}
return [h, s, l];
},
/**
* Return a new color that is lighter than this color.
* @param {Number} factor Lighter factor (0..1), default to 0.2
* @return Ext.draw.Color
*/
getLighter: function(factor) {
var hsl = this.getHSL();
factor = factor || this.lightnessFactor;
hsl[2] = Ext.Number.constrain(hsl[2] + factor, 0, 1);
return this.fromHSL(hsl[0], hsl[1], hsl[2]);
},
/**
* Return a new color that is darker than this color.
* @param {Number} factor Darker factor (0..1), default to 0.2
* @return Ext.draw.Color
*/
getDarker: function(factor) {
factor = factor || this.lightnessFactor;
return this.getLighter(-factor);
},
/**
* Return the color in the hex format, i.e. '#rrggbb'.
* @return {String}
*/
toString: function() {
var me = this,
round = Math.round,
r = round(me.r).toString(16),
g = round(me.g).toString(16),
b = round(me.b).toString(16);
r = (r.length == 1) ? '0' + r : r;
g = (g.length == 1) ? '0' + g : g;
b = (b.length == 1) ? '0' + b : b;
return ['#', r, g, b].join('');
},
/**
* Convert a color to hexadecimal format.
*
* @param {String|Array} color The color value (i.e 'rgb(255, 255, 255)', 'color: #ffffff').
* Can also be an Array, in this case the function handles the first member.
* @returns {String} The color in hexadecimal format.
*/
toHex: function(color) {
if (Ext.isArray(color)) {
color = color[0];
}
if (!Ext.isString(color)) {
return '';
}
if (color.substr(0, 1) === '#') {
return color;
}
var digits = this.colorToHexRe.exec(color);
if (Ext.isArray(digits)) {
var red = parseInt(digits[2], 10),
green = parseInt(digits[3], 10),
blue = parseInt(digits[4], 10),
rgb = blue | (green << 8) | (red << 16);
return digits[1] + '#' + ("000000" + rgb.toString(16)).slice(-6);
}
else {
return '';
}
},
/**
* Parse the string and create a new color.
*
* Supported formats: '#rrggbb', '#rgb', and 'rgb(r,g,b)'.
*
* If the string is not recognized, an undefined will be returned instead.
*
* @param {String} str Color in string.
* @returns Ext.draw.Color
*/
fromString: function(str) {
var values, r, g, b,
parse = parseInt;
if ((str.length == 4 || str.length == 7) && str.substr(0, 1) === '#') {
values = str.match(this.hexRe);
if (values) {
r = parse(values[1], 16) >> 0;
g = parse(values[2], 16) >> 0;
b = parse(values[3], 16) >> 0;
if (str.length == 4) {
r += (r * 16);
g += (g * 16);
b += (b * 16);
}
}
}
else {
values = str.match(this.rgbRe);
if (values) {
r = values[1];
g = values[2];
b = values[3];
}
}
return (typeof r == 'undefined') ? undefined : Ext.create('Ext.draw.Color', r, g, b);
},
/**
* Returns the gray value (0 to 255) of the color.
*
* The gray value is calculated using the formula r*0.3 + g*0.59 + b*0.11.
*
* @returns {Number}
*/
getGrayscale: function() {
// http://en.wikipedia.org/wiki/Grayscale#Converting_color_to_grayscale
return this.r * 0.3 + this.g * 0.59 + this.b * 0.11;
},
/**
* Create a new color based on the specified HSL values.
*
* @param {Number} h Hue component (0..359)
* @param {Number} s Saturation component (0..1)
* @param {Number} l Lightness component (0..1)
* @returns Ext.draw.Color
*/
fromHSL: function(h, s, l) {
var C, X, m, i, rgb = [],
abs = Math.abs,
floor = Math.floor;
if (s == 0 || h == null) {
// achromatic
rgb = [l, l, l];
}
else {
// http://en.wikipedia.org/wiki/HSL_and_HSV#From_HSL
// C is the chroma
// X is the second largest component
// m is the lightness adjustment
h /= 60;
C = s * (1 - abs(2 * l - 1));
X = C * (1 - abs(h - 2 * floor(h / 2) - 1));
m = l - C / 2;
switch (floor(h)) {
case 0:
rgb = [C, X, 0];
break;
case 1:
rgb = [X, C, 0];
break;
case 2:
rgb = [0, C, X];
break;
case 3:
rgb = [0, X, C];
break;
case 4:
rgb = [X, 0, C];
break;
case 5:
rgb = [C, 0, X];
break;
}
rgb = [rgb[0] + m, rgb[1] + m, rgb[2] + m];
}
return Ext.create('Ext.draw.Color', rgb[0] * 255, rgb[1] * 255, rgb[2] * 255);
}
}, function() {
var prototype = this.prototype;
//These functions are both static and instance. TODO: find a more elegant way of copying them
this.extend({
fromHSL: function() {
return prototype.fromHSL.apply(prototype, arguments);
},
fromString: function() {
return prototype.fromString.apply(prototype, arguments);
},
toHex: function() {
return prototype.toHex.apply(prototype, arguments);
}
});
});