'use strict';
/**
* @namespace Color
*/
var Randomizer = require('./randomizer.js');
/**
* @class Color
* @param {number} r - Red value.
* @param {number} g - Green value.
* @param {number} b - Blue value.
*/
function Color(r, g, b) {
this.r = r;
this.g = g;
this.b = b;
}
/**
* Generate a hex representation of the color.
* @returns {string}
*/
Color.prototype.toString = function() {
return Color.createFromRGB(this.r, this.g, this.b);
};
Color.random = Randomizer.nextColor;
Color.constants = {
red: '#FF0000',
RED: '#FF0000',
green: '#00FF00',
GREEN: '#00FF00',
blue: '#0000FF',
BLUE: '#0000FF',
yellow: '#FFFF00',
YELLOW: '#FFFF00',
cyan: '#00FFFF',
CYAN: '#00FFFF',
orange: '#FFA500',
ORANGE: '#FFA500',
white: '#FFFFFF',
WHITE: '#FFFFFF',
black: '#000000',
BLACK: '#000000',
gray: '#cccccc',
GRAY: '#CCCCCC',
grey: '#cccccc',
GREY: '#CCCCCC',
purple: '#9B30FF',
PURPLE: '#9B30FF'
};
var name;
for (name in Color.constants) {
Color[name] = Color.constants[name];
}
/**
* Helpers for createFromRGB
*/
/**
* Convert RGB to a hex string.
*
* @memberof Color
* @param {number} r - Red component.
* @param {number} g - Green component.
* @param {number} b - Blue component.
* @returns {string} Hex representation.
*/
function rgbToHex(r, g, b) {
r = Math.floor(r);
g = Math.floor(g);
b = Math.floor(b);
if (r > 255 || g > 255 || b > 255) {
throw 'Invalid color component';
}
return ((r << 16) | (g << 8) | b).toString(16);
}
function getColor(r, g, b) {
return '#' + ('000000' + rgbToHex(r, g, b)).slice(-6);
}
/**
* Create a hex color from RGB values.
*
* @param {number} r - Red value.
* @param {number} g - Green value.
* @param {number} b - Blue value .
* @returns {string}
*/
Color.createFromRGB = function(r, g, b) {
return getColor(r, g, b);
};
/**
* Generate a random red value.
*
* @returns {string} Hex representation of random red color.
*/
Color.randomRed = function() {
var r = Randomizer.nextInt(50, 255);
return Color.createFromRGB(r, 0, 0);
};
/**
* Generate a random green value.
*
* @returns {string} Hex representation of random green color.
*/
Color.randomGreen = function() {
var g = Randomizer.nextInt(50, 255);
return Color.createFromRGB(0, g, 0);
};
/**
* Generate a random blue value.
*
* @returns {string} Hex representation of random blue color.
*/
Color.randomBlue = function() {
var b = Randomizer.nextInt(50, 255);
return Color.createFromRGB(0, 0, b);
};
/**
* Creates a hex color string from a (r,g,b) value as well
* as a lightness value l from [0, 1]. To do this we convert
* the rgb color to hsl. Then we modify the l, take it back to
* rgb, and then convert to a color string.
*
* @param {number} r - The red color value.
* @param {number} g - The green color value.
* @param {number} b - The blue color value.
* @param {number} l - The lightness value [0,1].
* @returns {string} The hex color string.
*/
Color.createFromRGBL = function(r, g, b, l) {
var hsl = Color.rgbToHsl(r, g, b);
if (l < 0) {
l = 0;
}
if (l > 1) {
l = 1;
}
var rgb = Color.hslToRgb(hsl[0], hsl[1], l);
return Color.createFromRGB(rgb[0], rgb[1], rgb[2]);
};
/**
* Converts an RGB color value to HSL. Conversion formula
* adapted from http://en.wikipedia.org/wiki/HSL_color_space.
* Assumes r, g, and b are contained in the set [0, 255] and
* returns h, s, and l in the set [0, 1].
*
* @param {number} r - The red color value.
* @param {number} g - The green color value.
* @param {number} b - The blue color value.
* @returns {array} The HSL representation.
*/
Color.rgbToHsl = function(r, g, b) {
r /= 255, g /= 255, b /= 255;
var max = Math.max(r, g, b), min = Math.min(r, g, b);
var h, s, l = (max + min) / 2;
if (max == min) {
h = s = 0; // achromatic
}else {
var d = max - min;
s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
switch (max) {
case r: h = (g - b) / d + (g < b ? 6 : 0); break;
case g: h = (b - r) / d + 2; break;
case b: h = (r - g) / d + 4; break;
}
h /= 6;
}
return [h, s, l];
};
/**
* Helpers for hslToRgb
*/
/**
* Converts an HSL representation to RGB.
*
* @memberof Color
* @param {number} p
* @param {number} q
* @param {number} t
* @returns {number} RGB representation of component.
*/
function hue2rgb(p, q, t) {
if (t < 0) t += 1;
if (t > 1) t -= 1;
if (t < 1 / 6) return p + (q - p) * 6 * t;
if (t < 1 / 2) return q;
if (t < 2 / 3) return p + (q - p) * (2 / 3 - t) * 6;
return p;
}
/**
* Converts an HSL color value to RGB. Conversion formula
* adapted from http://en.wikipedia.org/wiki/HSL_color_space.
* Assumes h, s, and l are contained in the set [0, 1] and
* returns r, g, and b in the set [0, 255].
*
* @param {number} h - The hue.
* @param {number} s - The saturation.
* @param {number} l - The lightness.
* @returns {object} The RGB representation.
*/
Color.hslToRgb = function(h, s, l) {
var r, g, b;
if (s === 0) {
r = g = b = l; // achromatic
} else {
var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
var p = 2 * l - q;
r = hue2rgb(p, q, h + 1 / 3);
g = hue2rgb(p, q, h);
b = hue2rgb(p, q, h - 1 / 3);
}
return [r * 255, g * 255, b * 255];
};
/**
* Generate the average of two hex colors.
*
* @param {string} colorOne - First hex color.
* @param {string} colorTwo - Second hex color.
* @returns {string} Averaged hex color.
*/
Color.average = function(colorOne, colorTwo) {
// functions for converting to/from hex/dec
function getHex(num) { return num.toString(16); }
function getDec(hex) { return parseInt(hex, 16); }
var componentRegEx = /[\da-z]{2}/gi;
var componentsOne = colorOne.match(componentRegEx);
var componentsTwo = colorTwo.match(componentRegEx);
var averageHex = '#';
var colorOneComponent;
var colorTwoComponent;
var averageDec;
var h;
for (var i = 0; i < componentsOne.length; i++) {
colorOneComponent = getDec(componentsOne[i]);
colorTwoComponent = getDec(componentsTwo[i]);
averageDec = Math.floor((colorOneComponent + colorTwoComponent) >> 1);
h = getHex(averageDec);
if (h.length == 1) h = '0' + h;
averageHex += h;
}
return averageHex;
};
Color.getColor = function(colorString) {
return Color.constants[colorString];
};
Color.getHexColor = function(hexString) {
return hexString;
};
module.exports = Color;