projects / contractdashboard.git / commitdiff
search:
summary | shortlog | log | commit | commitdiff | tree
unified | plain
add php color library csscolor.php
add php color library csscolor.php

file:b/lib/csscolor.php (new)
  <?php
  /*
  csscolor.php
  Copyright 2004 Patrick Fitzgerald
  http://www.barelyfitz.com/projects/csscolor/
 
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.
 
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 
  define('CSS_COLOR_ERROR', 100);
 
  class CSS_Color
  {
  //==================================================
  //==PARAMETERS======================================
  //==================================================
 
  // $this->bg = array of CSS color values
  // $this->bg[0] is the bg color
  // $this->bg['+1'..'+5'] are lighter colors
  // $this->bg['-1'..'-5'] are darker colors
  var $bg = array();
 
  // $this->fg = array of foreground colors.
  // Each color corresponds to a background color.
  var $fg = array();
 
  // brightDiff is the minimum brightness difference
  // between the background and the foreground.
  // Note: you should not change this directly,
  // instead use setBrightDiff() and getBrightDiff()
  var $minBrightDiff = 126;
 
  // colorDiff is the minimum color difference
  // between the background and the foreground.
  // Note: you should not change this directly,
  // instead use setColorDiff() and getColorDiff()
  var $minColorDiff = 500;
 
  //==================================================
  //==CONSTRUCTOR=====================================
  //==================================================
 
  function CSS_Color($bgHex, $fgHex='')
  {
  // This is the constructor method for the class,
  // which is called when a new object is created.
 
 
  // Initialize the palette
  $this->setPalette($bgHex, $fgHex);
  }
 
  //==================================================
  //==METHODS=========================================
  //==================================================
 
  //--------------------------------------------------
  function setPalette($bgHex, $fgHex = '')
  {
  // Initialize the color palettes
 
  // If a foreground color was not specified,
  // just use the background color.
  if (!$fgHex) {
  $fgHex = $bgHex;
  }
 
  // Clear the existing palette
  $this->bg = array();
  $this->fg = array();
 
  // Make sure we got a valid hex value
  if (!$this->isHex($bgHex)) {
  $this->raiseError("background color '$bgHex' is not a hex color value",
  __FUNCTION__, __LINE__);
  return false;
  }
 
  // Set the bg color
  $this->bg[0] = $bgHex;
 
  $this->bg['+1'] = $this->lighten($bgHex, .85);
  $this->bg['+2'] = $this->lighten($bgHex, .75);
  $this->bg['+3'] = $this->lighten($bgHex, .5);
  $this->bg['+4'] = $this->lighten($bgHex, .25);
  $this->bg['+5'] = $this->lighten($bgHex, .1);
 
  $this->bg['-1'] = $this->darken($bgHex, .85);
  $this->bg['-2'] = $this->darken($bgHex, .75);
  $this->bg['-3'] = $this->darken($bgHex, .5);
  $this->bg['-4'] = $this->darken($bgHex, .25);
  $this->bg['-5'] = $this->darken($bgHex, .1);
 
  // Make sure we got a valid hex value
  if (!$this->isHex($fgHex)) {
  $this->raiseError("background color '$bgHex' is not a hex color value",
  __FUNCTION__, __LINE__);
  return false;
  }
 
  // Set up the foreground colors
  $this->fg[0] = $this->calcFG( $this->bg[0], $fgHex);
  $this->fg['+1'] = $this->calcFG( $this->bg['+1'], $fgHex);
  $this->fg['+2'] = $this->calcFG( $this->bg['+2'], $fgHex);
  $this->fg['+3'] = $this->calcFG( $this->bg['+3'], $fgHex);
  $this->fg['+4'] = $this->calcFG( $this->bg['+4'], $fgHex);
  $this->fg['+5'] = $this->calcFG( $this->bg['+5'], $fgHex);
  $this->fg['-1'] = $this->calcFG( $this->bg['-1'], $fgHex);
  $this->fg['-2'] = $this->calcFG( $this->bg['-2'], $fgHex);
  $this->fg['-3'] = $this->calcFG( $this->bg['-3'], $fgHex);
  $this->fg['-4'] = $this->calcFG( $this->bg['-4'], $fgHex);
  $this->fg['-5'] = $this->calcFG( $this->bg['-5'], $fgHex);
  }
 
  //--------------------------------------------------
  function lighten($hex, $percent)
  {
  return $this->mix($hex, $percent, 255);
  }
 
  //--------------------------------------------------
  function darken($hex, $percent)
  {
  return $this->mix($hex, $percent, 0);
  }
 
  //--------------------------------------------------
  function mix($hex, $percent, $mask)
  {
 
  // Make sure inputs are valid
  if (!is_numeric($percent) || $percent < 0 || $percent > 1) {
  $this->raiseError("percent=$percent is not valid",
  __FUNCTION__, __LINE__);
  return false;
  }
 
  if (!is_int($mask) || $mask < 0 || $mask > 255) {
  $this->raiseError("mask=$mask is not valid",
  __FUNCTION__, __LINE__);
  return false;
  }
 
  $rgb = $this->hex2RGB($hex);
  if (!is_array($rgb)) {
  // hex2RGB will raise an error
  return false;
  }
 
  for ($i=0; $i<3; $i++) {
  $rgb[$i] = round($rgb[$i] * $percent) + round($mask * (1-$percent));
 
  // In case rounding up causes us to go to 256
  if ($rgb[$i] > 255) {
  $rgb[$i] = 255;
  }
 
  }
  return $this->RGB2Hex($rgb);
  }
 
  //--------------------------------------------------
  function hex2RGB($hex)
  {
  //
  // Given a hex color (rrggbb or rgb),
  // returns an array (r, g, b) with decimal values
  // If $hex is not the correct format,
  // returns false.
  //
  // example:
  // $d = hex2RGB('#abc');
  // if (!$d) { error }
 
  // Regexp for a valid hex digit
  $d = '[a-fA-F0-9]';
 
  // Make sure $hex is valid
  if (preg_match("/^($d$d)($d$d)($d$d)\$/", $hex, $rgb)) {
 
  return array(
  hexdec($rgb[1]),
  hexdec($rgb[2]),
  hexdec($rgb[3])
  );
  }
  if (preg_match("/^($d)($d)($d)$/", $hex, $rgb)) {
 
  return array(
  hexdec($rgb[1] . $rgb[1]),
  hexdec($rgb[2] . $rgb[2]),
  hexdec($rgb[3] . $rgb[3])
  );
  }
 
  $this->raiseError("cannot convert hex '$hex' to RGB", __FUNCTION__, __LINE__);
  return false;
  }
 
  //--------------------------------------------------
  function RGB2Hex($rgb)
  {
  // Given an array(rval,gval,bval) consisting of
  // decimal color values (0-255), returns a hex string
  // suitable for use with CSS.
  // Returns false if the input is not in the correct format.
  // Example:
  // $h = RGB2Hex(array(255,0,255));
  // if (!$h) { error };
 
  // Make sure the input is valid
  if(!$this->isRGB($rgb)) {
  $this->raiseError("RGB value is not valid", __FUNCTION__, __LINE__);
  return false;
  }
 
  $hex = "";
  for($i=0; $i < 3; $i++) {
 
  // Convert the decimal digit to hex
  $hexDigit = dechex($rgb[$i]);
 
  // Add a leading zero if necessary
  if(strlen($hexDigit) == 1) {
  $hexDigit = "0" . $hexDigit;
  }
 
  // Append to the hex string
  $hex .= $hexDigit;
  }
 
  // Return the complete hex string
  return $hex;
  }
 
  //--------------------------------------------------
  function isHex($hex)
  {
  // Returns true if $hex is a valid CSS hex color.
  // The "#" character at the start is optional.
 
  // Regexp for a valid hex digit
  $d = '[a-fA-F0-9]';
 
  // Make sure $hex is valid
  if (preg_match("/^#?$d$d$d$d$d$d\$/", $hex) ||
  preg_match("/^#?$d$d$d\$/", $hex)) {
  return true;
  }
  return false;
  }
 
  //--------------------------------------------------
  function isRGB($rgb)
  {
  // Returns true if $rgb is an array with three valid
  // decimal color digits.
 
  if (!is_array($rgb) || count($rgb) != 3) {
  return false;
  }
 
  for($i=0; $i < 3; $i++) {
 
  // Get the decimal digit
  $dec = intval($rgb[$i]);
 
  // Make sure the decimal digit is between 0 and 255
  if (!is_int($dec) || $dec < 0 || $dec > 255) {
  return false;
  }
  }
 
  return true;
  }
 
  //--------------------------------------------------
  function calcFG($bgHex, $fgHex)
  {
  // Given a background color $bgHex and a foreground color $fgHex,
  // modifies the foreground color so it will have enough contrast
  // to be seen against the background color.
  //
  // The following parameters are used:
  // $this->minBrightDiff
  // $this->minColorDiff
 
  // Loop through brighter and darker versions
  // of the foreground color.
  // The numbers here represent the amount of
  // foreground color to mix with black and white.
  foreach (array(1, 0.75, 0.5, 0.25, 0) as $percent) {
 
  $darker = $this->darken($fgHex, $percent);
  $lighter = $this->lighten($fgHex, $percent);
 
  $darkerBrightDiff = $this->brightnessDiff($bgHex, $darker);
  $lighterBrightDiff = $this->brightnessDiff($bgHex, $lighter);
 
  if ($lighterBrightDiff > $darkerBrightDiff) {
  $newFG = $lighter;
  $newFGBrightDiff = $lighterBrightDiff;
  } else {
  $newFG = $darker;
  $newFGBrightDiff = $darkerBrightDiff;
  }
  $newFGColorDiff = $this->colorDiff($bgHex, $newFG);
 
  if ($newFGBrightDiff >= $this->minBrightDiff &&
  $newFGColorDiff >= $this->minColorDiff) {
  break;
  }
  }
 
  return $newFG;
  }
 
  //--------------------------------------------------
  function getMinBrightDiff()
  {
  return $this->minBrightDiff;
  }
  function setMinBrightDiff($b, $resetPalette = true)
  {
  $this->minBrightDiff = $b;
  if ($resetPalette) {
  $this->setPalette($this->bg[0],$this->fg[0]);
  }
  }
 
  //--------------------------------------------------
  function getMinColorDiff()
  {
  return $this->minColorDiff;
  }
  function setMinColorDiff($d, $resetPalette = true)
  {
  $this->minColorDiff = $d;
  if ($resetPalette) {
  $this->setPalette($this->bg[0],$this->fg[0]);
  }
  }
 
  //--------------------------------------------------
  function brightness($hex)
  {
  // Returns the brightness value for a color,
  // a number between zero and 178.
  // To allow for maximum readability, the difference between
  // the background brightness and the foreground brightness
  // should be greater than 125.
 
  $rgb = $this->hex2RGB($hex);
  if (!is_array($rgb)) {
  // hex2RGB will raise an error
  return false;
  }
 
  return( (($rgb[0] * 299) + ($rgb[1] * 587) + ($rgb[2] * 114)) / 1000 );
  }
 
  //--------------------------------------------------
  function brightnessDiff($hex1, $hex2)
  {
  // Returns the brightness value for a color,
  // a number between zero and 178.
  // To allow for maximum readability, the difference between
  // the background brightness and the foreground brightness
  // should be greater than 125.
 
  $b1 = $this->brightness($hex1);
  $b2 = $this->brightness($hex2);
  if (is_bool($b1) || is_bool($b2)) {
  return false;
  }
  return abs($b1 - $b2);
  }
 
  //--------------------------------------------------
  function colorDiff($hex1, $hex2)
  {
  // Returns the contrast between two colors,
  // an integer between 0 and 675.
  // To allow for maximum readability, the difference between
  // the background and the foreground color should be > 500.
 
  $rgb1 = $this->hex2RGB($hex1);
  $rgb2 = $this->hex2RGB($hex2);
 
  if (!is_array($rgb1) || !is_array($rgb2)) {
  // hex2RGB will raise an error
  return -1;
  }
 
  $r1 = $rgb1[0];
  $g1 = $rgb1[1];
  $b1 = $rgb1[2];
 
  $r2 = $rgb2[0];
  $g2 = $rgb2[1];
  $b2 = $rgb2[2];
 
  return(abs($r1-$r2) + abs($g1-$g2) + abs($b1-$b2));
  }
 
  }
 
  ?>
 
file:b/lib/csscolor.test.php (new)
  <?php
 
  // Tell the browser that this is CSS instead of HTML
  header("Content-type: text/css");
 
  // Get the color generating code
  include_once("csscolor.php");
 
  // Set the error handing for csscolor.
  // If an error occurs, print the error
  // within a CSS comment so we can see
  // it in the CSS file.
 
 
  // Define a couple color palettes
  $base = new CSS_Color('C9E3A6');
  $highlight = new CSS_Color('746B8E');
 
  // Trigger an error just to see what happens
  // $trigger = new CSS_Color('');
 
  ?>
 
 
  .box {
 
  /* Use the base color, two shades darker */
  background:#<?php echo $base->bg['-2'] ?>;
 
  /* Use the corresponding foreground color */
  color:#<?php echo $base->fg['-2'] ?>;
 
  /* Use the highlight color as a border */
  border:5px solid #<?php echo $highlight->bg['0'] ?>