/*
Colour.js
Functions for colour handling and processing.
http://www.safalra.com/web-design/javascript/colour-handling-and-processing/
The author of this program, Safalra (Stephen Morley), irrevocably releases all
rights to this program, with the intention of it becoming part of the public
domain. Because this program is released into the public domain, it comes with
no warranty either expressed or implied, to the extent permitted by law.
For more free and public domain JavaScript code by the same author, visit:
http://www.safalra.com/web-design/javascript/
*/
/* An abstract Colour implementation. Concrete Colour implementations should use
* an instance of this function as their prototype, and implement the getRGB and
* getHSL functions. getRGB should return an object representing the RGB
* components of this Colour, with the red, green, and blue components in the
* range [0,255] and the alpha component in the range [0,100]. getHSL should
* return an object representing the HSL components of this Colour, with the hue
* component in the range [0,360), the saturation and lightness components in
* the range [0,100], and the alpha component in the range [0,1].
*/
Roo.lib.Colour = function(){
/* Returns an object representing the RGBA components of this Colour. The red,
* green, and blue components are converted to integers in the range [0,255].
* The alpha is a value in the range [0,1].
*/
this.getIntegerRGB = function(){
// get the RGB components of this colour
var rgb = this.getRGB();
// return the integer components
return {
'r' : Math.round(rgb.r),
'g' : Math.round(rgb.g),
'b' : Math.round(rgb.b),
'a' : rgb.a
};
};
/* Returns an object representing the RGBA components of this Colour. The red,
* green, and blue components are converted to numbers in the range [0,100].
* The alpha is a value in the range [0,1].
*/
this.getPercentageRGB = function(){
// get the RGB components of this colour
var rgb = this.getRGB();
// return the percentage components
return {
'r' : 100 * rgb.r / 255,
'g' : 100 * rgb.g / 255,
'b' : 100 * rgb.b / 255,
'a' : rgb.a
};
};
/* Returns a string representing this Colour as a CSS hexadecimal RGB colour
* value - that is, a string of the form #RRGGBB where each of RR, GG, and BB
* are two-digit hexadecimal numbers.
*/
this.getCSSHexadecimalRGB = function(){
// get the integer RGB components
var rgb = this.getIntegerRGB();
// determine the hexadecimal equivalents
var r16 = rgb.r.toString(16);
var g16 = rgb.g.toString(16);
var b16 = rgb.b.toString(16);
// return the CSS RGB colour value
return '#'
+ (r16.length == 2 ? r16 : '0' + r16)
+ (g16.length == 2 ? g16 : '0' + g16)
+ (b16.length == 2 ? b16 : '0' + b16);
};
/* Returns a string representing this Colour as a CSS integer RGB colour
* value - that is, a string of the form rgb(r,g,b) where each of r, g, and b
* are integers in the range [0,255].
*/
this.getCSSIntegerRGB = function(){
// get the integer RGB components
var rgb = this.getIntegerRGB();
// return the CSS RGB colour value
return 'rgb(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ')';
};
/* Returns a string representing this Colour as a CSS integer RGBA colour
* value - that is, a string of the form rgba(r,g,b,a) where each of r, g, and
* b are integers in the range [0,255] and a is in the range [0,1].
*/
this.getCSSIntegerRGBA = function(){
// get the integer RGB components
var rgb = this.getIntegerRGB();
// return the CSS integer RGBA colour value
return 'rgb(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + rgb.a + ')';
};
/* Returns a string representing this Colour as a CSS percentage RGB colour
* value - that is, a string of the form rgb(r%,g%,b%) where each of r, g, and
* b are in the range [0,100].
*/
this.getCSSPercentageRGB = function(){
// get the percentage RGB components
var rgb = this.getPercentageRGB();
// return the CSS RGB colour value
return 'rgb(' + rgb.r + '%,' + rgb.g + '%,' + rgb.b + '%)';
};
/* Returns a string representing this Colour as a CSS percentage RGBA colour
* value - that is, a string of the form rgba(r%,g%,b%,a) where each of r, g,
* and b are in the range [0,100] and a is in the range [0,1].
*/
this.getCSSPercentageRGBA = function(){
// get the percentage RGB components
var rgb = this.getPercentageRGB();
// return the CSS percentage RGBA colour value
return 'rgb(' + rgb.r + '%,' + rgb.g + '%,' + rgb.b + '%,' + rgb.a + ')';
};
/* Returns a string representing this Colour as a CSS HSL colour value - that
* is, a string of the form hsl(h,s%,l%) where h is in the range [0,100] and
* s and l are in the range [0,100].
*/
this.getCSSHSL = function(){
// get the HSL components
var hsl = this.getHSL();
// return the CSS HSL colour value
return 'hsl(' + hsl.h + ',' + hsl.s + '%,' + hsl.l + '%)';
};
/* Returns a string representing this Colour as a CSS HSLA colour value - that
* is, a string of the form hsla(h,s%,l%,a) where h is in the range [0,100],
* s and l are in the range [0,100], and a is in the range [0,1].
*/
this.getCSSHSLA = function(){
// get the HSL components
var hsl = this.getHSL();
// return the CSS HSL colour value
return 'hsl(' + hsl.h + ',' + hsl.s + '%,' + hsl.l + '%,' + hsl.a + ')';
};
/* Sets the colour of the specified node to this Colour. This functions sets
* the CSS 'color' property for the node. The parameter is:
*
* node - the node whose colour should be set
*/
this.setNodeColour = function(node){
// set the colour of the node
node.style.color = this.getCSSHexadecimalRGB();
};
/* Sets the background colour of the specified node to this Colour. This
* functions sets the CSS 'background-color' property for the node. The
* parameter is:
*
* node - the node whose background colour should be set
*/
this.setNodeBackgroundColour = function(node){
// set the background colour of the node
node.style.backgroundColor = this.getCSSHexadecimalRGB();
};
// convert between formats..
this.toRGB= function()
{
var r = this.getIntegerRGB();
return new Roo.lib.RGBColour(r.r,r.g,r.b,r.a);
}
this.toHSL = function()
{
var hsl = this.getHSL();
// return the CSS HSL colour value
return new Roo.lib.HSLColour(hsl.h, hsl.s, hsl.l , hsl.a );
}
this.toHSV = function()
{
var rgb = this.toRGB();
var hsv = rgb.getHSV();
// return the CSS HSL colour value
return new Roo.lib.HSVColour(hsv.h, hsv.s, hsv.v , hsv.a );
}
// modify v = 0 ... 1 (eg. 0.5)
this.saturate = function(v)
{
var rgb = this.toRGB();
var hsv = rgb.getHSV();
return new Roo.lib.HSVColour(hsv.h, hsv.s * v, hsv.v , hsv.a );
}
}
/* Creates a colour specified in the RGB colour space, with an optional alpha
* component. The parameters are:
*
* r - the red component, clipped to the range [0,255]
* g - the green component, clipped to the range [0,255]
* b - the blue component, clipped to the range [0,255]
* a - the alpha component, clipped to the range [0,1] - this parameter is
* optional and defaults to 1
*/
Roo.lib.RGBColour = function (r, g, b, a){
// store the alpha component after clipping it if necessary
var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
// store the RGB components after clipping them if necessary
var rgb =
{
'r' : Math.max(0, Math.min(255, r)),
'g' : Math.max(0, Math.min(255, g)),
'b' : Math.max(0, Math.min(255, b))
};
// initialise the HSV and HSL components to null
var hsv = null;
var hsl = null;
/* Returns the HSV or HSL hue component of this RGBColour. The hue is in the
* range [0,360). The parameters are:
*
* maximum - the maximum of the RGB component values
* range - the range of the RGB component values
*/
function getHue(maximum, range){
// check whether the range is zero
if (range == 0){
// set the hue to zero (any hue is acceptable as the colour is grey)
var hue = 0;
}else{
// determine which of the components has the highest value and set the hue
switch (maximum){
// red has the highest value
case rgb.r:
var hue = (rgb.g - rgb.b) / range * 60;
if (hue < 0) hue += 360;
break;
// green has the highest value
case rgb.g:
var hue = (rgb.b - rgb.r) / range * 60 + 120;
break;
// blue has the highest value
case rgb.b:
var hue = (rgb.r - rgb.g) / range * 60 + 240;
break;
}
}
// return the hue
return hue;
}
/* Calculates and stores the HSV components of this RGBColour so that they can
* be returned be the getHSV function.
*/
function calculateHSV(){
// get the maximum and range of the RGB component values
var maximum = Math.max(rgb.r, rgb.g, rgb.b);
var range = maximum - Math.min(rgb.r, rgb.g, rgb.b);
// store the HSV components
hsv =
{
'h' : getHue(maximum, range),
's' : (maximum == 0 ? 0 : 100 * range / maximum),
'v' : maximum / 2.55
};
}
/* Calculates and stores the HSL components of this RGBColour so that they can
* be returned be the getHSL function.
*/
function calculateHSL(){
// get the maximum and range of the RGB component values
var maximum = Math.max(rgb.r, rgb.g, rgb.b);
var range = maximum - Math.min(rgb.r, rgb.g, rgb.b);
// determine the lightness in the range [0,1]
var l = maximum / 255 - range / 510;
// store the HSL components
hsl =
{
'h' : getHue(maximum, range),
's' : (range == 0 ? 0 : range / 2.55 / (l < 0.5 ? l * 2 : 2 - l * 2)),
'l' : 100 * l
};
}
/* Returns the RGB and alpha components of this RGBColour as an object with r,
* g, b, and a properties. r, g, and b are in the range [0,255] and a is in
* the range [0,1].
*/
this.getRGB = function(){
// return the RGB components
return {
'r' : rgb.r,
'g' : rgb.g,
'b' : rgb.b,
'a' : alpha
};
};
/* Returns the HSV and alpha components of this RGBColour as an object with h,
* s, v, and a properties. h is in the range [0,360), s and v are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSV = function(){
// calculate the HSV components if necessary
if (hsv == null) calculateHSV();
// return the HSV components
return {
'h' : hsv.h,
's' : hsv.s,
'v' : hsv.v,
'a' : alpha
};
};
/* Returns the HSL and alpha components of this RGBColour as an object with h,
* s, l, and a properties. h is in the range [0,360), s and l are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSL = function(){
// calculate the HSV components if necessary
if (hsl == null) calculateHSL();
// return the HSL components
return {
'h' : hsl.h,
's' : hsl.s,
'l' : hsl.l,
'a' : alpha
};
};
}
Roo.lib.RGBColour.prototype = new Roo.lib.Colour();
/* Creates a colour specified in the HSV colour space, with an optional alpha
* component. The parameters are:
*
* h - the hue component, wrapped to the range [0,360)
* s - the saturation component, clipped to the range [0,100]
* v - the value component, clipped to the range [0,100]
* a - the alpha component, clipped to the range [0,1] - this parameter is
* optional and defaults to 1
*/
Roo.lib.HSVColour = function (h, s, v, a){
// store the alpha component after clipping it if necessary
var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
// store the HSV components after clipping or wrapping them if necessary
var hsv =
{
'h' : (h % 360 + 360) % 360,
's' : Math.max(0, Math.min(100, s)),
'v' : Math.max(0, Math.min(100, v))
};
// initialise the RGB and HSL components to null
var rgb = null;
var hsl = null;
/* Calculates and stores the RGB components of this HSVColour so that they can
* be returned be the getRGB function.
*/
function calculateRGB(){
// check whether the saturation is zero
if (hsv.s == 0){
// set the colour to the appropriate shade of grey
var r = hsv.v;
var g = hsv.v;
var b = hsv.v;
}else{
// set some temporary values
var f = hsv.h / 60 - Math.floor(hsv.h / 60);
var p = hsv.v * (1 - hsv.s / 100);
var q = hsv.v * (1 - hsv.s / 100 * f);
var t = hsv.v * (1 - hsv.s / 100 * (1 - f));
// set the RGB colour components to their temporary values
switch (Math.floor(hsv.h / 60)){
case 0: var r = hsv.v; var g = t; var b = p; break;
case 1: var r = q; var g = hsv.v; var b = p; break;
case 2: var r = p; var g = hsv.v; var b = t; break;
case 3: var r = p; var g = q; var b = hsv.v; break;
case 4: var r = t; var g = p; var b = hsv.v; break;
case 5: var r = hsv.v; var g = p; var b = q; break;
}
}
// store the RGB components
rgb =
{
'r' : r * 2.55,
'g' : g * 2.55,
'b' : b * 2.55
};
}
/* Calculates and stores the HSL components of this HSVColour so that they can
* be returned be the getHSL function.
*/
function calculateHSL(){
// determine the lightness in the range [0,100]
var l = (2 - hsv.s / 100) * hsv.v / 2;
// store the HSL components
hsl =
{
'h' : hsv.h,
's' : hsv.s * hsv.v / (l < 50 ? l * 2 : 200 - l * 2),
'l' : l
};
// correct a division-by-zero error
if (isNaN(hsl.s)) hsl.s = 0;
}
/* Returns the RGB and alpha components of this HSVColour as an object with r,
* g, b, and a properties. r, g, and b are in the range [0,255] and a is in
* the range [0,1].
*/
this.getRGB = function(){
// calculate the RGB components if necessary
if (rgb == null) calculateRGB();
// return the RGB components
return {
'r' : rgb.r,
'g' : rgb.g,
'b' : rgb.b,
'a' : alpha
};
};
/* Returns the HSV and alpha components of this HSVColour as an object with h,
* s, v, and a properties. h is in the range [0,360), s and v are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSV = function(){
// return the HSV components
return {
'h' : hsv.h,
's' : hsv.s,
'v' : hsv.v,
'a' : alpha
};
};
/* Returns the HSL and alpha components of this HSVColour as an object with h,
* s, l, and a properties. h is in the range [0,360), s and l are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSL = function(){
// calculate the HSL components if necessary
if (hsl == null) calculateHSL();
// return the HSL components
return {
'h' : hsl.h,
's' : hsl.s,
'l' : hsl.l,
'a' : alpha
};
};
}
Roo.lib.HSVColour.prototype = new Roo.lib.Colour();
/* Creates a colour specified in the HSL colour space, with an optional alpha
* component. The parameters are:
*
* h - the hue component, wrapped to the range [0,360)
* s - the saturation component, clipped to the range [0,100]
* l - the lightness component, clipped to the range [0,100]
* a - the alpha component, clipped to the range [0,1] - this parameter is
* optional and defaults to 1
*/
Roo.lib.HSLColour = function(h, s, l, a){
// store the alpha component after clipping it if necessary
var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
// store the HSL components after clipping or wrapping them if necessary
var hsl =
{
'h' : (h % 360 + 360) % 360,
's' : Math.max(0, Math.min(100, s)),
'l' : Math.max(0, Math.min(100, l))
};
// initialise the RGB and HSV components to null
var rgb = null;
var hsv = null;
/* Calculates and stores the RGB components of this HSLColour so that they can
* be returned be the getRGB function.
*/
function calculateRGB(){
// check whether the saturation is zero
if (hsl.s == 0){
// store the RGB components representing the appropriate shade of grey
rgb =
{
'r' : hsl.l * 2.55,
'g' : hsl.l * 2.55,
'b' : hsl.l * 2.55
};
}else{
// set some temporary values
var p = hsl.l < 50
? hsl.l * (1 + hsl.s / 100)
: hsl.l + hsl.s - hsl.l * hsl.s / 100;
var q = 2 * hsl.l - p;
// initialise the RGB components
rgb =
{
'r' : (h + 120) / 60 % 6,
'g' : h / 60,
'b' : (h + 240) / 60 % 6
};
// loop over the RGB components
for (var key in rgb){
// ensure that the property is not inherited from the root object
if (rgb.hasOwnProperty(key)){
// set the component to its value in the range [0,100]
if (rgb[key] < 1){
rgb[key] = q + (p - q) * rgb[key];
}else if (rgb[key] < 3){
rgb[key] = p;
}else if (rgb[key] < 4){
rgb[key] = q + (p - q) * (4 - rgb[key]);
}else{
rgb[key] = q;
}
// set the component to its value in the range [0,255]
rgb[key] *= 2.55;
}
}
}
}
/* Calculates and stores the HSV components of this HSLColour so that they can
* be returned be the getHSL function.
*/
function calculateHSV(){
// set a temporary value
var t = hsl.s * (hsl.l < 50 ? hsl.l : 100 - hsl.l) / 100;
// store the HSV components
hsv =
{
'h' : hsl.h,
's' : 200 * t / (hsl.l + t),
'v' : t + hsl.l
};
// correct a division-by-zero error
if (isNaN(hsv.s)) hsv.s = 0;
}
/* Returns the RGB and alpha components of this HSLColour as an object with r,
* g, b, and a properties. r, g, and b are in the range [0,255] and a is in
* the range [0,1].
*/
this.getRGB = function(){
// calculate the RGB components if necessary
if (rgb == null) calculateRGB();
// return the RGB components
return {
'r' : rgb.r,
'g' : rgb.g,
'b' : rgb.b,
'a' : alpha
};
};
/* Returns the HSV and alpha components of this HSLColour as an object with h,
* s, v, and a properties. h is in the range [0,360), s and v are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSV = function(){
// calculate the HSV components if necessary
if (hsv == null) calculateHSV();
// return the HSV components
return {
'h' : hsv.h,
's' : hsv.s,
'v' : hsv.v,
'a' : alpha
};
};
/* Returns the HSL and alpha components of this HSLColour as an object with h,
* s, l, and a properties. h is in the range [0,360), s and l are in the range
* [0,100], and a is in the range [0,1].
*/
this.getHSL = function(){
// return the HSL components
return {
'h' : hsl.h,
's' : hsl.s,
'l' : hsl.l,
'a' : alpha
};
};
}
Roo.lib.HSLColour.prototype = new Roo.lib.Colour();