5 Functions for colour handling and processing.
7 http://www.safalra.com/web-design/javascript/colour-handling-and-processing/
9 The author of this program, Safalra (Stephen Morley), irrevocably releases all
10 rights to this program, with the intention of it becoming part of the public
11 domain. Because this program is released into the public domain, it comes with
12 no warranty either expressed or implied, to the extent permitted by law.
14 For more free and public domain JavaScript code by the same author, visit:
15 http://www.safalra.com/web-design/javascript/
20 /* An abstract Colour implementation. Concrete Colour implementations should use
21 * an instance of this function as their prototype, and implement the getRGB and
22 * getHSL functions. getRGB should return an object representing the RGB
23 * components of this Colour, with the red, green, and blue components in the
24 * range [0,255] and the alpha component in the range [0,100]. getHSL should
25 * return an object representing the HSL components of this Colour, with the hue
26 * component in the range [0,360), the saturation and lightness components in
27 * the range [0,100], and the alpha component in the range [0,1].
29 Roo.lib.Colour = function(){
31 /* Returns an object representing the RGBA components of this Colour. The red,
32 * green, and blue components are converted to integers in the range [0,255].
33 * The alpha is a value in the range [0,1].
35 this.getIntegerRGB = function(){
37 // get the RGB components of this colour
38 var rgb = this.getRGB();
40 // return the integer components
42 'r' : Math.round(rgb.r),
43 'g' : Math.round(rgb.g),
44 'b' : Math.round(rgb.b),
50 /* Returns an object representing the RGBA components of this Colour. The red,
51 * green, and blue components are converted to numbers in the range [0,100].
52 * The alpha is a value in the range [0,1].
54 this.getPercentageRGB = function(){
56 // get the RGB components of this colour
57 var rgb = this.getRGB();
59 // return the percentage components
61 'r' : 100 * rgb.r / 255,
62 'g' : 100 * rgb.g / 255,
63 'b' : 100 * rgb.b / 255,
69 /* Returns a string representing this Colour as a CSS hexadecimal RGB colour
70 * value - that is, a string of the form #RRGGBB where each of RR, GG, and BB
71 * are two-digit hexadecimal numbers.
73 this.getCSSHexadecimalRGB = function(){
75 // get the integer RGB components
76 var rgb = this.getIntegerRGB();
78 // determine the hexadecimal equivalents
79 var r16 = rgb.r.toString(16);
80 var g16 = rgb.g.toString(16);
81 var b16 = rgb.b.toString(16);
83 // return the CSS RGB colour value
85 + (r16.length == 2 ? r16 : '0' + r16)
86 + (g16.length == 2 ? g16 : '0' + g16)
87 + (b16.length == 2 ? b16 : '0' + b16);
91 /* Returns a string representing this Colour as a CSS integer RGB colour
92 * value - that is, a string of the form rgb(r,g,b) where each of r, g, and b
93 * are integers in the range [0,255].
95 this.getCSSIntegerRGB = function(){
97 // get the integer RGB components
98 var rgb = this.getIntegerRGB();
100 // return the CSS RGB colour value
101 return 'rgb(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ')';
105 /* Returns a string representing this Colour as a CSS integer RGBA colour
106 * value - that is, a string of the form rgba(r,g,b,a) where each of r, g, and
107 * b are integers in the range [0,255] and a is in the range [0,1].
109 this.getCSSIntegerRGBA = function(){
111 // get the integer RGB components
112 var rgb = this.getIntegerRGB();
114 // return the CSS integer RGBA colour value
115 return 'rgb(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + rgb.a + ')';
119 /* Returns a string representing this Colour as a CSS percentage RGB colour
120 * value - that is, a string of the form rgb(r%,g%,b%) where each of r, g, and
121 * b are in the range [0,100].
123 this.getCSSPercentageRGB = function(){
125 // get the percentage RGB components
126 var rgb = this.getPercentageRGB();
128 // return the CSS RGB colour value
129 return 'rgb(' + rgb.r + '%,' + rgb.g + '%,' + rgb.b + '%)';
133 /* Returns a string representing this Colour as a CSS percentage RGBA colour
134 * value - that is, a string of the form rgba(r%,g%,b%,a) where each of r, g,
135 * and b are in the range [0,100] and a is in the range [0,1].
137 this.getCSSPercentageRGBA = function(){
139 // get the percentage RGB components
140 var rgb = this.getPercentageRGB();
142 // return the CSS percentage RGBA colour value
143 return 'rgb(' + rgb.r + '%,' + rgb.g + '%,' + rgb.b + '%,' + rgb.a + ')';
147 /* Returns a string representing this Colour as a CSS HSL colour value - that
148 * is, a string of the form hsl(h,s%,l%) where h is in the range [0,100] and
149 * s and l are in the range [0,100].
151 this.getCSSHSL = function(){
153 // get the HSL components
154 var hsl = this.getHSL();
156 // return the CSS HSL colour value
157 return 'hsl(' + hsl.h + ',' + hsl.s + '%,' + hsl.l + '%)';
161 /* Returns a string representing this Colour as a CSS HSLA colour value - that
162 * is, a string of the form hsla(h,s%,l%,a) where h is in the range [0,100],
163 * s and l are in the range [0,100], and a is in the range [0,1].
165 this.getCSSHSLA = function(){
167 // get the HSL components
168 var hsl = this.getHSL();
170 // return the CSS HSL colour value
171 return 'hsl(' + hsl.h + ',' + hsl.s + '%,' + hsl.l + '%,' + hsl.a + ')';
175 /* Sets the colour of the specified node to this Colour. This functions sets
176 * the CSS 'color' property for the node. The parameter is:
178 * node - the node whose colour should be set
180 this.setNodeColour = function(node){
182 // set the colour of the node
183 node.style.color = this.getCSSHexadecimalRGB();
187 /* Sets the background colour of the specified node to this Colour. This
188 * functions sets the CSS 'background-color' property for the node. The
191 * node - the node whose background colour should be set
193 this.setNodeBackgroundColour = function(node){
195 // set the background colour of the node
196 node.style.backgroundColor = this.getCSSHexadecimalRGB();
199 // convert between formats..
200 this.toRGB= function()
202 var r = this.getIntegerRGB();
203 return new Roo.lib.RGBColour(r.r,r,g,r,b,r.a);
206 this.toHSL = function()
208 var hsl = this.getHSL();
209 // return the CSS HSL colour value
210 return new Roo.lib.HSLColour(hsl.h, hsl.s, hsl.l , hsl.a );
214 this.toHSV = function()
216 var rgb = this.toRGB();
217 var hsv = rgb.getHSV();
218 var hsl = this.getHSL();
219 // return the CSS HSL colour value
220 return new Roo.lib.HSVColour(hsv.h, hsv.s, hsv.v , hsv.a );
233 /* Creates a colour specified in the RGB colour space, with an optional alpha
234 * component. The parameters are:
236 * r - the red component, clipped to the range [0,255]
237 * g - the green component, clipped to the range [0,255]
238 * b - the blue component, clipped to the range [0,255]
239 * a - the alpha component, clipped to the range [0,1] - this parameter is
240 * optional and defaults to 1
242 Roo.lib.RGBColour = function (r, g, b, a){
244 // store the alpha component after clipping it if necessary
245 var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
247 // store the RGB components after clipping them if necessary
250 'r' : Math.max(0, Math.min(255, r)),
251 'g' : Math.max(0, Math.min(255, g)),
252 'b' : Math.max(0, Math.min(255, b))
255 // initialise the HSV and HSL components to null
259 /* Returns the HSV or HSL hue component of this RGBColour. The hue is in the
260 * range [0,360). The parameters are:
262 * maximum - the maximum of the RGB component values
263 * range - the range of the RGB component values
265 function getHue(maximum, range){
267 // check whether the range is zero
270 // set the hue to zero (any hue is acceptable as the colour is grey)
275 // determine which of the components has the highest value and set the hue
278 // red has the highest value
280 var hue = (rgb.g - rgb.b) / range * 60;
281 if (hue < 0) hue += 360;
284 // green has the highest value
286 var hue = (rgb.b - rgb.r) / range * 60 + 120;
289 // blue has the highest value
291 var hue = (rgb.r - rgb.g) / range * 60 + 240;
303 /* Calculates and stores the HSV components of this RGBColour so that they can
304 * be returned be the getHSV function.
306 function calculateHSV(){
308 // get the maximum and range of the RGB component values
309 var maximum = Math.max(rgb.r, rgb.g, rgb.b);
310 var range = maximum - Math.min(rgb.r, rgb.g, rgb.b);
312 // store the HSV components
315 'h' : getHue(maximum, range),
316 's' : (maximum == 0 ? 0 : 100 * range / maximum),
322 /* Calculates and stores the HSL components of this RGBColour so that they can
323 * be returned be the getHSL function.
325 function calculateHSL(){
327 // get the maximum and range of the RGB component values
328 var maximum = Math.max(rgb.r, rgb.g, rgb.b);
329 var range = maximum - Math.min(rgb.r, rgb.g, rgb.b);
331 // determine the lightness in the range [0,1]
332 var l = maximum / 255 - range / 510;
334 // store the HSL components
337 'h' : getHue(maximum, range),
338 's' : (range == 0 ? 0 : range / 2.55 / (l < 0.5 ? l * 2 : 2 - l * 2)),
344 /* Returns the RGB and alpha components of this RGBColour as an object with r,
345 * g, b, and a properties. r, g, and b are in the range [0,255] and a is in
348 this.getRGB = function(){
350 // return the RGB components
360 /* Returns the HSV and alpha components of this RGBColour as an object with h,
361 * s, v, and a properties. h is in the range [0,360), s and v are in the range
362 * [0,100], and a is in the range [0,1].
364 this.getHSV = function(){
366 // calculate the HSV components if necessary
367 if (hsv == null) calculateHSV();
369 // return the HSV components
379 /* Returns the HSL and alpha components of this RGBColour as an object with h,
380 * s, l, and a properties. h is in the range [0,360), s and l are in the range
381 * [0,100], and a is in the range [0,1].
383 this.getHSL = function(){
385 // calculate the HSV components if necessary
386 if (hsl == null) calculateHSL();
388 // return the HSL components
399 Roo.lib.RGBColour.prototype = new Roo.lib.Colour();
402 /* Creates a colour specified in the HSV colour space, with an optional alpha
403 * component. The parameters are:
405 * h - the hue component, wrapped to the range [0,360)
406 * s - the saturation component, clipped to the range [0,100]
407 * v - the value component, clipped to the range [0,100]
408 * a - the alpha component, clipped to the range [0,1] - this parameter is
409 * optional and defaults to 1
411 Roo.lib.HSVColour = function (h, s, v, a){
413 // store the alpha component after clipping it if necessary
414 var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
416 // store the HSV components after clipping or wrapping them if necessary
419 'h' : (h % 360 + 360) % 360,
420 's' : Math.max(0, Math.min(100, s)),
421 'v' : Math.max(0, Math.min(100, v))
424 // initialise the RGB and HSL components to null
428 /* Calculates and stores the RGB components of this HSVColour so that they can
429 * be returned be the getRGB function.
431 function calculateRGB(){
433 // check whether the saturation is zero
436 // set the colour to the appropriate shade of grey
443 // set some temporary values
444 var f = hsv.h / 60 - Math.floor(hsv.h / 60);
445 var p = hsv.v * (1 - hsv.s / 100);
446 var q = hsv.v * (1 - hsv.s / 100 * f);
447 var t = hsv.v * (1 - hsv.s / 100 * (1 - f));
449 // set the RGB colour components to their temporary values
450 switch (Math.floor(hsv.h / 60)){
451 case 0: var r = hsv.v; var g = t; var b = p; break;
452 case 1: var r = q; var g = hsv.v; var b = p; break;
453 case 2: var r = p; var g = hsv.v; var b = t; break;
454 case 3: var r = p; var g = q; var b = hsv.v; break;
455 case 4: var r = t; var g = p; var b = hsv.v; break;
456 case 5: var r = hsv.v; var g = p; var b = q; break;
461 // store the RGB components
471 /* Calculates and stores the HSL components of this HSVColour so that they can
472 * be returned be the getHSL function.
474 function calculateHSL(){
476 // determine the lightness in the range [0,100]
477 var l = (2 - hsv.s / 100) * hsv.v / 2;
479 // store the HSL components
483 's' : hsv.s * hsv.v / (l < 50 ? l * 2 : 200 - l * 2),
487 // correct a division-by-zero error
488 if (isNaN(hsl.s)) hsl.s = 0;
492 /* Returns the RGB and alpha components of this HSVColour as an object with r,
493 * g, b, and a properties. r, g, and b are in the range [0,255] and a is in
496 this.getRGB = function(){
498 // calculate the RGB components if necessary
499 if (rgb == null) calculateRGB();
501 // return the RGB components
511 /* Returns the HSV and alpha components of this HSVColour as an object with h,
512 * s, v, and a properties. h is in the range [0,360), s and v are in the range
513 * [0,100], and a is in the range [0,1].
515 this.getHSV = function(){
517 // return the HSV components
527 /* Returns the HSL and alpha components of this HSVColour as an object with h,
528 * s, l, and a properties. h is in the range [0,360), s and l are in the range
529 * [0,100], and a is in the range [0,1].
531 this.getHSL = function(){
533 // calculate the HSL components if necessary
534 if (hsl == null) calculateHSL();
536 // return the HSL components
547 Roo.lib.HSVColour.prototype = new Roo.lib.Colour();
550 /* Creates a colour specified in the HSL colour space, with an optional alpha
551 * component. The parameters are:
553 * h - the hue component, wrapped to the range [0,360)
554 * s - the saturation component, clipped to the range [0,100]
555 * l - the lightness component, clipped to the range [0,100]
556 * a - the alpha component, clipped to the range [0,1] - this parameter is
557 * optional and defaults to 1
560 Roo.lib.HSLColour = function(h, s, l, a){
562 // store the alpha component after clipping it if necessary
563 var alpha = (a === undefined ? 1 : Math.max(0, Math.min(1, a)));
565 // store the HSL components after clipping or wrapping them if necessary
568 'h' : (h % 360 + 360) % 360,
569 's' : Math.max(0, Math.min(100, s)),
570 'l' : Math.max(0, Math.min(100, l))
573 // initialise the RGB and HSV components to null
577 /* Calculates and stores the RGB components of this HSLColour so that they can
578 * be returned be the getRGB function.
580 function calculateRGB(){
582 // check whether the saturation is zero
585 // store the RGB components representing the appropriate shade of grey
595 // set some temporary values
597 ? hsl.l * (1 + hsl.s / 100)
598 : hsl.l + hsl.s - hsl.l * hsl.s / 100;
599 var q = 2 * hsl.l - p;
601 // initialise the RGB components
604 'r' : (h + 120) / 60 % 6,
606 'b' : (h + 240) / 60 % 6
609 // loop over the RGB components
610 for (var key in rgb){
612 // ensure that the property is not inherited from the root object
613 if (rgb.hasOwnProperty(key)){
615 // set the component to its value in the range [0,100]
617 rgb[key] = q + (p - q) * rgb[key];
618 }else if (rgb[key] < 3){
620 }else if (rgb[key] < 4){
621 rgb[key] = q + (p - q) * (4 - rgb[key]);
626 // set the component to its value in the range [0,255]
637 /* Calculates and stores the HSV components of this HSLColour so that they can
638 * be returned be the getHSL function.
640 function calculateHSV(){
642 // set a temporary value
643 var t = hsl.s * (hsl.l < 50 ? hsl.l : 100 - hsl.l) / 100;
645 // store the HSV components
649 's' : 200 * t / (hsl.l + t),
653 // correct a division-by-zero error
654 if (isNaN(hsv.s)) hsv.s = 0;
658 /* Returns the RGB and alpha components of this HSLColour as an object with r,
659 * g, b, and a properties. r, g, and b are in the range [0,255] and a is in
662 this.getRGB = function(){
664 // calculate the RGB components if necessary
665 if (rgb == null) calculateRGB();
667 // return the RGB components
677 /* Returns the HSV and alpha components of this HSLColour as an object with h,
678 * s, v, and a properties. h is in the range [0,360), s and v are in the range
679 * [0,100], and a is in the range [0,1].
681 this.getHSV = function(){
683 // calculate the HSV components if necessary
684 if (hsv == null) calculateHSV();
686 // return the HSV components
696 /* Returns the HSL and alpha components of this HSLColour as an object with h,
697 * s, l, and a properties. h is in the range [0,360), s and l are in the range
698 * [0,100], and a is in the range [0,1].
700 this.getHSL = function(){
702 // return the HSL components
713 Roo.lib.HSLColour.prototype = new Roo.lib.Colour();