How can I change the color of a specific word using Imagick in PHP?

Question

I'm currently using annotateImage to add some text to an image.

/* Black text */
$draw->setFillColor('black');

/* Font properties */
$draw->setFont('Bookman-DemiItalic');
$draw->setFontSize( 30 );

$image->annotateImage($draw, 10, 45, 0, 'The fox jumped over the lazy dog');

This currently displays all the text in black. I'm looking for a way to change the color of the word fox to red, but I'm out of ideas.

How can I achieve this?

Answer 1

As suggested by Danack's comment, here's my solution if anyone needs it. The parseText function looks for <span> tags with the attributes, color, font, size and returns an array.

The <span color="red">fox</span> jumped over the lazy <span color="green">dog</span>.

In the above text, the word fox will have a color=red attribute, and dog will have color=green.

Using the array, we can draw the regular text, track the positioning and draw the stylized texts as well.

function parseText($txt) {
  if ( strstr($txt, '<span') ) {
    $txt = preg_split('@(<span(?:\\\?.)*?>(?:\\\?.)*?</span>)@', $txt, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
    $arr = array();
    foreach ( $txt as $t ) {
      if ( strstr($t, '<span') ) {
        $tag = array();
        preg_match('@<span\s*((?:\\\?.)*?)\s*>((?:\\\?.)*?)</span>@', $t, $m);
        $attrs = $m[1];
        $inner = $m[2];
        if ( $attrs ) {
          $attrs = preg_split('@((?:\\\?.)*?=["\'](?:\\\?.)*?["\'])\s*@', $attrs, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
          foreach ( $attrs as $a ) {
            $a = explode('=', $a);
            $tag[ $a[0] ] = trim($a[1], '"\'');
          }
        }
        $tag['text'] = $inner;
        $arr[] = $tag;
      } else {
        $arr[] = array( 'text' => $t );
      }
      $txt = $arr;
    }
  }
  return $txt;
}

function newStyle($image, $draw, $t, &$width) {
  if ( $t['color'] )  $draw->setFillColor($t['color']);
  if ( $t['size']  )  $draw->setFontSize($t['size']);
  if ( $t['font']  )  $draw->setFont($t['font']);
  $metrics = $image->queryFontMetrics($draw, $t['text'], FALSE);
  $width = $metrics['textWidth'];
}

// To use it

function defaultStyle($draw) {
  $draw->setFillColor('black');
  $draw->setFont('Bookman-DemiItalic');
  $draw->setFontSize(20);
}

defaultStyle($draw);

$txt = 'The <span color="red">fox</span> jumped over the lazy <span color="green">dog</span>.';
$x = 45;
$y = 45;
$txt = parseText($txt);
if ( is_array($txt) ) {
  foreach ( $txt as $t ) {
    defaultStyle($draw);
    newStyle($image, $draw, $t, $width);
    $image->annotateImage($draw, $x, $y, 0, $t['text']);
    $x += $width;
  }
} else {
  $image->annotateImage($draw, $x, $y, 0, $txt);
}