| 1 |
<?php |
| 2 |
/** |
| 3 |
* Color utility and conversion |
| 4 |
* |
| 5 |
* Represents a color value, and converts between RGB/HSV/XYZ/Lab/HSL |
| 6 |
* |
| 7 |
* Example: |
| 8 |
* $color = new Jetpack_Color(0xFFFFFF); |
| 9 |
* |
| 10 |
* @author Harold Asbridge <hasbridge@gmail.com> |
| 11 |
* @author Matt Wiebe <wiebe@automattic.com> |
| 12 |
* @license http://www.opensource.org/licenses/MIT |
| 13 |
*/ |
| 14 |
|
| 15 |
class Jetpack_Color { |
| 16 |
/** |
| 17 |
* @var int |
| 18 |
*/ |
| 19 |
protected $color = 0; |
| 20 |
|
| 21 |
/** |
| 22 |
* Initialize object |
| 23 |
* |
| 24 |
* @param string|array $color A color of the type $type |
| 25 |
* @param string $type The type of color we will construct from. |
| 26 |
* One of hex (default), rgb, hsl, int |
| 27 |
*/ |
| 28 |
public function __construct( $color = null, $type = 'hex' ) { |
| 29 |
if ( $color ) { |
| 30 |
switch ( $type ) { |
| 31 |
case 'hex': |
| 32 |
$this->fromHex( $color ); |
| 33 |
break; |
| 34 |
case 'rgb': |
| 35 |
if ( is_array( $color ) && count( $color ) == 3 ) { |
| 36 |
list( $r, $g, $b ) = array_values( $color ); |
| 37 |
$this->fromRgbInt( $r, $g, $b ); |
| 38 |
} |
| 39 |
break; |
| 40 |
case 'hsl': |
| 41 |
if ( is_array( $color ) && count( $color ) == 3 ) { |
| 42 |
list( $h, $s, $l ) = array_values( $color ); |
| 43 |
$this->fromHsl( $h, $s, $l ); |
| 44 |
} |
| 45 |
break; |
| 46 |
case 'int': |
| 47 |
$this->fromInt( $color ); |
| 48 |
break; |
| 49 |
default: |
| 50 |
// there is no default. |
| 51 |
break; |
| 52 |
} |
| 53 |
} |
| 54 |
} |
| 55 |
|
| 56 |
/** |
| 57 |
* Init color from hex value |
| 58 |
* |
| 59 |
* @param string $hexValue |
| 60 |
* |
| 61 |
* @return Jetpack_Color |
| 62 |
*/ |
| 63 |
public function fromHex($hexValue) { |
| 64 |
$hexValue = str_replace( '#', '', $hexValue ); |
| 65 |
// handle short hex codes like #fff |
| 66 |
if ( 3 === strlen( $hexValue ) ) { |
| 67 |
$short = $hexValue; |
| 68 |
$i = 0; |
| 69 |
$hexValue = ''; |
| 70 |
while ( $i < 3 ) { |
| 71 |
$chunk = substr($short, $i, 1 ); |
| 72 |
$hexValue .= $chunk . $chunk; |
| 73 |
$i++; |
| 74 |
} |
| 75 |
} |
| 76 |
$intValue = hexdec( $hexValue ); |
| 77 |
|
| 78 |
if ( $intValue < 0 || $intValue > 16777215 ) { |
| 79 |
throw new RangeException( $hexValue . " out of valid color code range" ); |
| 80 |
} |
| 81 |
|
| 82 |
$this->color = $intValue; |
| 83 |
|
| 84 |
return $this; |
| 85 |
} |
| 86 |
|
| 87 |
/** |
| 88 |
* Init color from integer RGB values |
| 89 |
* |
| 90 |
* @param int $red |
| 91 |
* @param int $green |
| 92 |
* @param int $blue |
| 93 |
* |
| 94 |
* @return Jetpack_Color |
| 95 |
*/ |
| 96 |
public function fromRgbInt($red, $green, $blue) |
| 97 |
{ |
| 98 |
if ( $red < 0 || $red > 255 ) |
| 99 |
throw new RangeException( "Red value " . $red . " out of valid color code range" ); |
| 100 |
|
| 101 |
if ( $green < 0 || $green > 255 ) |
| 102 |
throw new RangeException( "Green value " . $green . " out of valid color code range" ); |
| 103 |
|
| 104 |
if ( $blue < 0 || $blue > 255 ) |
| 105 |
throw new RangeException( "Blue value " . $blue . " out of valid color code range" ); |
| 106 |
|
| 107 |
$this->color = (int)(($red << 16) + ($green << 8) + $blue); |
| 108 |
|
| 109 |
return $this; |
| 110 |
} |
| 111 |
|
| 112 |
/** |
| 113 |
* Init color from hex RGB values |
| 114 |
* |
| 115 |
* @param string $red |
| 116 |
* @param string $green |
| 117 |
* @param string $blue |
| 118 |
* |
| 119 |
* @return Jetpack_Color |
| 120 |
*/ |
| 121 |
public function fromRgbHex($red, $green, $blue) |
| 122 |
{ |
| 123 |
return $this->fromRgbInt(hexdec($red), hexdec($green), hexdec($blue)); |
| 124 |
} |
| 125 |
|
| 126 |
/** |
| 127 |
* Converts an HSL color value to RGB. Conversion formula |
| 128 |
* adapted from http://en.wikipedia.org/wiki/HSL_color_space. |
| 129 |
* @param int $h Hue. [0-360] |
| 130 |
* @param in $s Saturation [0, 100] |
| 131 |
* @param int $l Lightness [0, 100] |
| 132 |
*/ |
| 133 |
public function fromHsl( $h, $s, $l ) { |
| 134 |
$h /= 360; $s /= 100; $l /= 100; |
| 135 |
|
| 136 |
if ( $s == 0 ) { |
| 137 |
$r = $g = $b = $l; // achromatic |
| 138 |
} |
| 139 |
else { |
| 140 |
$q = $l < 0.5 ? $l * ( 1 + $s ) : $l + $s - $l * $s; |
| 141 |
$p = 2 * $l - $q; |
| 142 |
$r = $this->hue2rgb( $p, $q, $h + 1/3 ); |
| 143 |
$g = $this->hue2rgb( $p, $q, $h ); |
| 144 |
$b = $this->hue2rgb( $p, $q, $h - 1/3 ); |
| 145 |
} |
| 146 |
|
| 147 |
return $this->fromRgbInt( $r * 255, $g * 255, $b * 255 ); |
| 148 |
} |
| 149 |
|
| 150 |
/** |
| 151 |
* Helper function for Jetpack_Color::fromHsl() |
| 152 |
*/ |
| 153 |
private function hue2rgb( $p, $q, $t ) { |
| 154 |
if ( $t < 0 ) $t += 1; |
| 155 |
if ( $t > 1 ) $t -= 1; |
| 156 |
if ( $t < 1/6 ) return $p + ( $q - $p ) * 6 * $t; |
| 157 |
if ( $t < 1/2 ) return $q; |
| 158 |
if ( $t < 2/3 ) return $p + ( $q - $p ) * ( 2/3 - $t ) * 6; |
| 159 |
return $p; |
| 160 |
} |
| 161 |
|
| 162 |
/** |
| 163 |
* Init color from integer value |
| 164 |
* |
| 165 |
* @param int $intValue |
| 166 |
* |
| 167 |
* @return Jetpack_Color |
| 168 |
*/ |
| 169 |
public function fromInt($intValue) |
| 170 |
{ |
| 171 |
if ( $intValue < 0 || $intValue > 16777215 ) |
| 172 |
throw new RangeException( $intValue . " out of valid color code range" ); |
| 173 |
|
| 174 |
$this->color = $intValue; |
| 175 |
|
| 176 |
return $this; |
| 177 |
} |
| 178 |
|
| 179 |
/** |
| 180 |
* Convert color to hex |
| 181 |
* |
| 182 |
* @return string |
| 183 |
*/ |
| 184 |
public function toHex() |
| 185 |
{ |
| 186 |
return str_pad(dechex($this->color), 6, '0', STR_PAD_LEFT); |
| 187 |
} |
| 188 |
|
| 189 |
/** |
| 190 |
* Convert color to RGB array (integer values) |
| 191 |
* |
| 192 |
* @return array |
| 193 |
*/ |
| 194 |
public function toRgbInt() |
| 195 |
{ |
| 196 |
return array( |
| 197 |
'red' => (int)(255 & ($this->color >> 16)), |
| 198 |
'green' => (int)(255 & ($this->color >> 8)), |
| 199 |
'blue' => (int)(255 & ($this->color)) |
| 200 |
); |
| 201 |
} |
| 202 |
|
| 203 |
/** |
| 204 |
* Convert color to RGB array (hex values) |
| 205 |
* |
| 206 |
* @return array |
| 207 |
*/ |
| 208 |
public function toRgbHex() |
| 209 |
{ |
| 210 |
$r = array(); |
| 211 |
foreach ($this->toRgbInt() as $item) { |
| 212 |
$r[] = dechex($item); |
| 213 |
} |
| 214 |
return $r; |
| 215 |
} |
| 216 |
|
| 217 |
/** |
| 218 |
* Get Hue/Saturation/Value for the current color |
| 219 |
* (float values, slow but accurate) |
| 220 |
* |
| 221 |
* @return array |
| 222 |
*/ |
| 223 |
public function toHsvFloat() |
| 224 |
{ |
| 225 |
$rgb = $this->toRgbInt(); |
| 226 |
|
| 227 |
$rgbMin = min($rgb); |
| 228 |
$rgbMax = max($rgb); |
| 229 |
|
| 230 |
$hsv = array( |
| 231 |
'hue' => 0, |
| 232 |
'sat' => 0, |
| 233 |
'val' => $rgbMax |
| 234 |
); |
| 235 |
|
| 236 |
// If v is 0, color is black |
| 237 |
if ($hsv['val'] == 0) { |
| 238 |
return $hsv; |
| 239 |
} |
| 240 |
|
| 241 |
// Normalize RGB values to 1 |
| 242 |
$rgb['red'] /= $hsv['val']; |
| 243 |
$rgb['green'] /= $hsv['val']; |
| 244 |
$rgb['blue'] /= $hsv['val']; |
| 245 |
$rgbMin = min($rgb); |
| 246 |
$rgbMax = max($rgb); |
| 247 |
|
| 248 |
// Calculate saturation |
| 249 |
$hsv['sat'] = $rgbMax - $rgbMin; |
| 250 |
if ($hsv['sat'] == 0) { |
| 251 |
$hsv['hue'] = 0; |
| 252 |
return $hsv; |
| 253 |
} |
| 254 |
|
| 255 |
// Normalize saturation to 1 |
| 256 |
$rgb['red'] = ($rgb['red'] - $rgbMin) / ($rgbMax - $rgbMin); |
| 257 |
$rgb['green'] = ($rgb['green'] - $rgbMin) / ($rgbMax - $rgbMin); |
| 258 |
$rgb['blue'] = ($rgb['blue'] - $rgbMin) / ($rgbMax - $rgbMin); |
| 259 |
$rgbMin = min($rgb); |
| 260 |
$rgbMax = max($rgb); |
| 261 |
|
| 262 |
// Calculate hue |
| 263 |
if ($rgbMax == $rgb['red']) { |
| 264 |
$hsv['hue'] = 0.0 + 60 * ($rgb['green'] - $rgb['blue']); |
| 265 |
if ($hsv['hue'] < 0) { |
| 266 |
$hsv['hue'] += 360; |
| 267 |
} |
| 268 |
} else if ($rgbMax == $rgb['green']) { |
| 269 |
$hsv['hue'] = 120 + (60 * ($rgb['blue'] - $rgb['red'])); |
| 270 |
} else { |
| 271 |
$hsv['hue'] = 240 + (60 * ($rgb['red'] - $rgb['green'])); |
| 272 |
} |
| 273 |
|
| 274 |
return $hsv; |
| 275 |
} |
| 276 |
|
| 277 |
/** |
| 278 |
* Get HSV values for color |
| 279 |
* (integer values from 0-255, fast but less accurate) |
| 280 |
* |
| 281 |
* @return int |
| 282 |
*/ |
| 283 |
public function toHsvInt() |
| 284 |
{ |
| 285 |
$rgb = $this->toRgbInt(); |
| 286 |
|
| 287 |
$rgbMin = min($rgb); |
| 288 |
$rgbMax = max($rgb); |
| 289 |
|
| 290 |
$hsv = array( |
| 291 |
'hue' => 0, |
| 292 |
'sat' => 0, |
| 293 |
'val' => $rgbMax |
| 294 |
); |
| 295 |
|
| 296 |
// If value is 0, color is black |
| 297 |
if ($hsv['val'] == 0) { |
| 298 |
return $hsv; |
| 299 |
} |
| 300 |
|
| 301 |
// Calculate saturation |
| 302 |
$hsv['sat'] = round(255 * ($rgbMax - $rgbMin) / $hsv['val']); |
| 303 |
if ($hsv['sat'] == 0) { |
| 304 |
$hsv['hue'] = 0; |
| 305 |
return $hsv; |
| 306 |
} |
| 307 |
|
| 308 |
// Calculate hue |
| 309 |
if ($rgbMax == $rgb['red']) { |
| 310 |
$hsv['hue'] = round(0 + 43 * ($rgb['green'] - $rgb['blue']) / ($rgbMax - $rgbMin)); |
| 311 |
} else if ($rgbMax == $rgb['green']) { |
| 312 |
$hsv['hue'] = round(85 + 43 * ($rgb['blue'] - $rgb['red']) / ($rgbMax - $rgbMin)); |
| 313 |
} else { |
| 314 |
$hsv['hue'] = round(171 + 43 * ($rgb['red'] - $rgb['green']) / ($rgbMax - $rgbMin)); |
| 315 |
} |
| 316 |
if ($hsv['hue'] < 0) { |
| 317 |
$hsv['hue'] += 255; |
| 318 |
} |
| 319 |
|
| 320 |
return $hsv; |
| 321 |
} |
| 322 |
|
| 323 |
/** |
| 324 |
* Converts an RGB color value to HSL. Conversion formula |
| 325 |
* adapted from http://en.wikipedia.org/wiki/HSL_color_space. |
| 326 |
* Assumes r, g, and b are contained in the set [0, 255] and |
| 327 |
* returns h in [0, 360], s in [0, 100], l in [0, 100] |
| 328 |
* |
| 329 |
* @return Array The HSL representation |
| 330 |
*/ |
| 331 |
public function toHsl() { |
| 332 |
list( $r, $g, $b ) = array_values( $this->toRgbInt() ); |
| 333 |
$r /= 255; $g /= 255; $b /= 255; |
| 334 |
$max = max( $r, $g, $b ); |
| 335 |
$min = min( $r, $g, $b ); |
| 336 |
$h = $s = $l = ( $max + $min ) / 2; |
| 337 |
#var_dump( array( compact('max', 'min', 'r', 'g', 'b')) ); |
| 338 |
if ( $max == $min ) { |
| 339 |
$h = $s = 0; // achromatic |
| 340 |
} |
| 341 |
else { |
| 342 |
$d = $max - $min; |
| 343 |
$s = $l > 0.5 ? $d / ( 2 - $max - $min ) : $d / ( $max + $min ); |
| 344 |
switch ( $max ) { |
| 345 |
case $r: |
| 346 |
$h = ( $g - $b ) / $d + ( $g < $b ? 6 : 0 ); |
| 347 |
break; |
| 348 |
case $g: |
| 349 |
$h = ( $b - $r ) / $d + 2; |
| 350 |
break; |
| 351 |
case $b: |
| 352 |
$h = ( $r - $g ) / $d + 4; |
| 353 |
break; |
| 354 |
} |
| 355 |
$h /= 6; |
| 356 |
} |
| 357 |
$h = (int) round( $h * 360 ); |
| 358 |
$s = (int) round( $s * 100 ); |
| 359 |
$l = (int) round( $l * 100 ); |
| 360 |
return compact( 'h', 's', 'l' ); |
| 361 |
} |
| 362 |
|
| 363 |
public function toCSS( $type = 'hex', $alpha = 1 ) { |
| 364 |
switch ( $type ) { |
| 365 |
case 'hex': |
| 366 |
return $this->toString(); |
| 367 |
break; |
| 368 |
case 'rgb': |
| 369 |
case 'rgba': |
| 370 |
list( $r, $g, $b ) = array_values( $this->toRgbInt() ); |
| 371 |
if ( is_numeric( $alpha ) && $alpha < 1 ) { |
| 372 |
return "rgba( {$r}, {$g}, {$b}, $alpha )"; |
| 373 |
} |
| 374 |
else { |
| 375 |
return "rgb( {$r}, {$g}, {$b} )"; |
| 376 |
} |
| 377 |
break; |
| 378 |
case 'hsl': |
| 379 |
case 'hsla': |
| 380 |
list( $h, $s, $l ) = array_values( $this->toHsl() ); |
| 381 |
if ( is_numeric( $alpha ) && $alpha < 1 ) { |
| 382 |
return "hsla( {$h}, {$s}, {$l}, $alpha )"; |
| 383 |
} |
| 384 |
else { |
| 385 |
return "hsl( {$h}, {$s}, {$l} )"; |
| 386 |
} |
| 387 |
break; |
| 388 |
default: |
| 389 |
return $this->toString(); |
| 390 |
break; |
| 391 |
} |
| 392 |
} |
| 393 |
|
| 394 |
/** |
| 395 |
* Get current color in XYZ format |
| 396 |
* |
| 397 |
* @return array |
| 398 |
*/ |
| 399 |
public function toXyz() |
| 400 |
{ |
| 401 |
$rgb = $this->toRgbInt(); |
| 402 |
|
| 403 |
// Normalize RGB values to 1 |
| 404 |
|
| 405 |
$rgb_new = array(); |
| 406 |
foreach ($rgb as $item) { |
| 407 |
$rgb_new[] = $item / 255; |
| 408 |
} |
| 409 |
$rgb = $rgb_new; |
| 410 |
|
| 411 |
$rgb_new = array(); |
| 412 |
foreach ($rgb as $item) { |
| 413 |
if ($item > 0.04045) { |
| 414 |
$item = pow((($item + 0.055) / 1.055), 2.4); |
| 415 |
} else { |
| 416 |
$item = $item / 12.92; |
| 417 |
} |
| 418 |
$rgb_new[] = $item * 100; |
| 419 |
} |
| 420 |
$rgb = $rgb_new; |
| 421 |
|
| 422 |
//Observer. = 2�, Illuminant = D65 |
| 423 |
$xyz = array( |
| 424 |
'x' => ($rgb['red'] * 0.4124) + ($rgb['green'] * 0.3576) + ($rgb['blue'] * 0.1805), |
| 425 |
'y' => ($rgb['red'] * 0.2126) + ($rgb['green'] * 0.7152) + ($rgb['blue'] * 0.0722), |
| 426 |
'z' => ($rgb['red'] * 0.0193) + ($rgb['green'] * 0.1192) + ($rgb['blue'] * 0.9505) |
| 427 |
); |
| 428 |
|
| 429 |
return $xyz; |
| 430 |
} |
| 431 |
|
| 432 |
/** |
| 433 |
* Get color CIE-Lab values |
| 434 |
* |
| 435 |
* @return array |
| 436 |
*/ |
| 437 |
public function toLabCie() |
| 438 |
{ |
| 439 |
$xyz = $this->toXyz(); |
| 440 |
|
| 441 |
//Ovserver = 2*, Iluminant=D65 |
| 442 |
$xyz['x'] /= 95.047; |
| 443 |
$xyz['y'] /= 100; |
| 444 |
$xyz['z'] /= 108.883; |
| 445 |
|
| 446 |
$xyz_new = array(); |
| 447 |
foreach ($xyz as $item) { |
| 448 |
if ($item > 0.008856) { |
| 449 |
$xyz_new[] = pow($item, 1/3); |
| 450 |
} else { |
| 451 |
$xyz_new[] = (7.787 * $item) + (16 / 116); |
| 452 |
} |
| 453 |
} |
| 454 |
$xyz = $xyz_new; |
| 455 |
|
| 456 |
$lab = array( |
| 457 |
'l' => (116 * $xyz['y']) - 16, |
| 458 |
'a' => 500 * ($xyz['x'] - $xyz['y']), |
| 459 |
'b' => 200 * ($xyz['y'] - $xyz['z']) |
| 460 |
); |
| 461 |
|
| 462 |
return $lab; |
| 463 |
} |
| 464 |
|
| 465 |
/** |
| 466 |
* Convert color to integer |
| 467 |
* |
| 468 |
* @return int |
| 469 |
*/ |
| 470 |
public function toInt() |
| 471 |
{ |
| 472 |
return $this->color; |
| 473 |
} |
| 474 |
|
| 475 |
/** |
| 476 |
* Alias of toString() |
| 477 |
* |
| 478 |
* @return string |
| 479 |
*/ |
| 480 |
public function __toString() |
| 481 |
{ |
| 482 |
return $this->toString(); |
| 483 |
} |
| 484 |
|
| 485 |
/** |
| 486 |
* Get color as string |
| 487 |
* |
| 488 |
* @return string |
| 489 |
*/ |
| 490 |
public function toString() |
| 491 |
{ |
| 492 |
$str = $this->toHex(); |
| 493 |
return strtoupper("#{$str}"); |
| 494 |
} |
| 495 |
|
| 496 |
/** |
| 497 |
* Get the distance between this color and the given color |
| 498 |
* |
| 499 |
* @param Jetpack_Color $color |
| 500 |
* |
| 501 |
* @return int |
| 502 |
*/ |
| 503 |
public function getDistanceRgbFrom(Jetpack_Color $color) |
| 504 |
{ |
| 505 |
$rgb1 = $this->toRgbInt(); |
| 506 |
$rgb2 = $color->toRgbInt(); |
| 507 |
|
| 508 |
$rDiff = abs($rgb1['red'] - $rgb2['red']); |
| 509 |
$gDiff = abs($rgb1['green'] - $rgb2['green']); |
| 510 |
$bDiff = abs($rgb1['blue'] - $rgb2['blue']); |
| 511 |
|
| 512 |
// Sum of RGB differences |
| 513 |
$diff = $rDiff + $gDiff + $bDiff; |
| 514 |
return $diff; |
| 515 |
} |
| 516 |
|
| 517 |
/** |
| 518 |
* Get distance from the given color using the Delta E method |
| 519 |
* |
| 520 |
* @param Jetpack_Color $color |
| 521 |
* |
| 522 |
* @return float |
| 523 |
*/ |
| 524 |
public function getDistanceLabFrom(Jetpack_Color $color) |
| 525 |
{ |
| 526 |
$lab1 = $this->toLabCie(); |
| 527 |
$lab2 = $color->toLabCie(); |
| 528 |
|
| 529 |
$lDiff = abs($lab2['l'] - $lab1['l']); |
| 530 |
$aDiff = abs($lab2['a'] - $lab1['a']); |
| 531 |
$bDiff = abs($lab2['b'] - $lab1['b']); |
| 532 |
|
| 533 |
$delta = sqrt($lDiff + $aDiff + $bDiff); |
| 534 |
|
| 535 |
return $delta; |
| 536 |
} |
| 537 |
|
| 538 |
public function toLuminosity() { |
| 539 |
extract( $this->toRgbInt() ); |
| 540 |
return 0.2126 * pow( $red / 255, 2.2 ) + 0.7152 * pow( $green / 255, 2.2 ) + 0.0722 * pow( $blue / 255, 2.2); |
| 541 |
} |
| 542 |
|
| 543 |
/** |
| 544 |
* Get distance between colors using luminance. |
| 545 |
* Should be more than 5 for readable contrast |
| 546 |
* |
| 547 |
* @param Jetpack_Color $color Another color |
| 548 |
* @return float |
| 549 |
*/ |
| 550 |
public function getDistanceLuminosityFrom(Jetpack_Color $color) { |
| 551 |
$L1 = $this->toLuminosity(); |
| 552 |
$L2 = $color->toLuminosity(); |
| 553 |
if ( $L1 > $L2 ) { |
| 554 |
return ( $L1 + 0.05 ) / ( $L2 + 0.05 ); |
| 555 |
} |
| 556 |
else{ |
| 557 |
return ( $L2 + 0.05 ) / ( $L1 + 0.05 ); |
| 558 |
} |
| 559 |
} |
| 560 |
|
| 561 |
public function getMaxContrastColor() { |
| 562 |
$lum = $this->toLuminosity(); |
| 563 |
$color = new Jetpack_Color; |
| 564 |
$hex = ( $lum >= 0.5 ) ? '000000' : 'ffffff'; |
| 565 |
return $color->fromHex( $hex ); |
| 566 |
} |
| 567 |
|
| 568 |
public function getGrayscaleContrastingColor( $contrast = false ) { |
| 569 |
if ( ! $contrast ) { |
| 570 |
return $this->getMaxContrastColor(); |
| 571 |
} |
| 572 |
// don't allow less than 5 |
| 573 |
$target_contrast = ( $contrast < 5 ) ? 5 : $contrast; |
| 574 |
$color = $this->getMaxContrastColor(); |
| 575 |
$contrast = $color->getDistanceLuminosityFrom( $this ); |
| 576 |
|
| 577 |
// if current max contrast is less than the target contrast, we had wishful thinking. |
| 578 |
if ( $contrast <= $target_contrast ) { |
| 579 |
return $color; |
| 580 |
} |
| 581 |
|
| 582 |
$incr = ( '#000000' === $color->toString() ) ? 1 : -1; |
| 583 |
while ( $contrast > $target_contrast ) { |
| 584 |
$color = $color->incrementLightness( $incr ); |
| 585 |
$contrast = $color->getDistanceLuminosityFrom( $this ); |
| 586 |
} |
| 587 |
|
| 588 |
return $color; |
| 589 |
} |
| 590 |
|
| 591 |
/** |
| 592 |
* Gets a readable contrasting color. $this is assumed to be the text and $color the background color. |
| 593 |
* @param object $bg_color A Color object that will be compared against $this |
| 594 |
* @param integer $min_contrast The minimum contrast to achieve, if possible. |
| 595 |
* @return object A Color object, an increased contrast $this compared against $bg_color |
| 596 |
*/ |
| 597 |
public function getReadableContrastingColor( $bg_color = false, $min_contrast = 5 ) { |
| 598 |
if ( ! $bg_color || ! is_a( $bg_color, 'Jetpack_Color' ) ) { |
| 599 |
return $this; |
| 600 |
} |
| 601 |
// you shouldn't use less than 5, but you might want to. |
| 602 |
$target_contrast = $min_contrast; |
| 603 |
// working things |
| 604 |
$contrast = $bg_color->getDistanceLuminosityFrom( $this ); |
| 605 |
$max_contrast_color = $bg_color->getMaxContrastColor(); |
| 606 |
$max_contrast = $max_contrast_color->getDistanceLuminosityFrom( $bg_color ); |
| 607 |
|
| 608 |
// if current max contrast is less than the target contrast, we had wishful thinking. |
| 609 |
// still, go max |
| 610 |
if ( $max_contrast <= $target_contrast ) { |
| 611 |
return $max_contrast_color; |
| 612 |
} |
| 613 |
// or, we might already have sufficient contrast |
| 614 |
if ( $contrast >= $target_contrast ) { |
| 615 |
return $this; |
| 616 |
} |
| 617 |
|
| 618 |
$incr = ( 0 === $max_contrast_color->toInt() ) ? -1 : 1; |
| 619 |
while ( $contrast < $target_contrast ) { |
| 620 |
$this->incrementLightness( $incr ); |
| 621 |
$contrast = $bg_color->getDistanceLuminosityFrom( $this ); |
| 622 |
// infininite loop prevention: you never know. |
| 623 |
if ( $this->color === 0 || $this->color === 16777215 ) { |
| 624 |
break; |
| 625 |
} |
| 626 |
} |
| 627 |
|
| 628 |
return $this; |
| 629 |
} |
| 630 |
|
| 631 |
/** |
| 632 |
* Detect if color is grayscale |
| 633 |
* |
| 634 |
* @param int @threshold |
| 635 |
* |
| 636 |
* @return bool |
| 637 |
*/ |
| 638 |
public function isGrayscale($threshold = 16) |
| 639 |
{ |
| 640 |
$rgb = $this->toRgbInt(); |
| 641 |
|
| 642 |
// Get min and max rgb values, then difference between them |
| 643 |
$rgbMin = min($rgb); |
| 644 |
$rgbMax = max($rgb); |
| 645 |
$diff = $rgbMax - $rgbMin; |
| 646 |
|
| 647 |
return $diff < $threshold; |
| 648 |
} |
| 649 |
|
| 650 |
/** |
| 651 |
* Get the closest matching color from the given array of colors |
| 652 |
* |
| 653 |
* @param array $colors array of integers or Jetpack_Color objects |
| 654 |
* |
| 655 |
* @return mixed the array key of the matched color |
| 656 |
*/ |
| 657 |
public function getClosestMatch(array $colors) |
| 658 |
{ |
| 659 |
$matchDist = 10000; |
| 660 |
$matchKey = null; |
| 661 |
foreach($colors as $key => $color) { |
| 662 |
if (false === ($color instanceof Jetpack_Color)) { |
| 663 |
$c = new Jetpack_Color($color); |
| 664 |
} |
| 665 |
$dist = $this->getDistanceLabFrom($c); |
| 666 |
if ($dist < $matchDist) { |
| 667 |
$matchDist = $dist; |
| 668 |
$matchKey = $key; |
| 669 |
} |
| 670 |
} |
| 671 |
|
| 672 |
return $matchKey; |
| 673 |
} |
| 674 |
|
| 675 |
/* TRANSFORMS */ |
| 676 |
|
| 677 |
public function darken( $amount = 5 ) { |
| 678 |
return $this->incrementLightness( - $amount ); |
| 679 |
} |
| 680 |
|
| 681 |
public function lighten( $amount = 5 ) { |
| 682 |
return $this->incrementLightness( $amount ); |
| 683 |
} |
| 684 |
|
| 685 |
public function incrementLightness( $amount ) { |
| 686 |
$hsl = $this->toHsl(); |
| 687 |
extract( $hsl ); |
| 688 |
$l += $amount; |
| 689 |
if ( $l < 0 ) $l = 0; |
| 690 |
if ( $l > 100 ) $l = 100; |
| 691 |
return $this->fromHsl( $h, $s, $l ); |
| 692 |
} |
| 693 |
|
| 694 |
public function saturate( $amount = 15 ) { |
| 695 |
return $this->incrementSaturation( $amount ); |
| 696 |
} |
| 697 |
|
| 698 |
public function desaturate( $amount = 15 ) { |
| 699 |
return $this->incrementSaturation( - $amount ); |
| 700 |
} |
| 701 |
|
| 702 |
public function incrementSaturation( $amount ) { |
| 703 |
$hsl = $this->toHsl(); |
| 704 |
extract( $hsl ); |
| 705 |
$s += $amount; |
| 706 |
if ( $s < 0 ) $s = 0; |
| 707 |
if ( $s > 100 ) $s = 100; |
| 708 |
return $this->fromHsl( $h, $s, $l ); |
| 709 |
} |
| 710 |
|
| 711 |
public function toGrayscale() { |
| 712 |
$hsl = $this->toHsl(); |
| 713 |
extract( $hsl ); |
| 714 |
$s = 0; |
| 715 |
return $this->fromHsl( $h, $s, $l ); |
| 716 |
} |
| 717 |
|
| 718 |
public function getComplement() { |
| 719 |
return $this->incrementHue( 180 ); |
| 720 |
} |
| 721 |
|
| 722 |
public function getSplitComplement( $step = 1 ) { |
| 723 |
$incr = 180 + ( $step * 30 ); |
| 724 |
return $this->incrementHue( $incr ); |
| 725 |
} |
| 726 |
|
| 727 |
public function getAnalog( $step = 1 ) { |
| 728 |
$incr = $step * 30; |
| 729 |
return $this->incrementHue( $incr ); |
| 730 |
} |
| 731 |
|
| 732 |
public function getTetrad( $step = 1 ) { |
| 733 |
$incr = $step * 60; |
| 734 |
return $this->incrementHue( $incr ); |
| 735 |
} |
| 736 |
|
| 737 |
public function getTriad( $step = 1 ) { |
| 738 |
$incr = $step * 120; |
| 739 |
return $this->incrementHue( $incr ); |
| 740 |
} |
| 741 |
|
| 742 |
public function incrementHue( $amount ) { |
| 743 |
$hsl = $this->toHsl(); |
| 744 |
extract( $hsl ); |
| 745 |
$h = ( $h + $amount ) % 360; |
| 746 |
if ( $h < 0 ) $h = 360 - $h; |
| 747 |
return $this->fromHsl( $h, $s, $l ); |
| 748 |
} |
| 749 |
|
| 750 |
} // class Jetpack_Color |
| 751 |
|
