Centering multiple lines of text using GD and PHP

Question

I am trying to print a few lines of text on an image and center them.

i.e.

      This is a line with text.

Now I have only the left position for the entire line. Any shortcuts on how this works? I think it could be getttfbox on the whole line, then the line breaks, and then centers the new text inside this larger ttfbox. This is a pain in the ass ...

EDIT: Made up a solution:

    foreach ( $strings as $index => $string ) {
        $parts = explode ( "\n", $string['string'] );
        if ( count ( $parts ) > 1 ) {
            $bounds = imagettfbbox ( intval($string['fontsize']), 0, $font, $string['string'] );
            $width = $bounds[2] - $bounds[0];
            $height = $bounds[3] - $bounds[5];
            $line_height = $height / count ( $parts );

            foreach ( $parts as $index => $part ) {
                $bounds = imagettfbbox ( intval($string['fontsize']), 0, $font, $part );
                $new_width = $bounds[2] - $bounds[0];
                $diff = ( $width - $new_width ) / 2;
                $new_left = $string['left'] + $diff;

                $new_string = $string;
                $new_string['left'] = $new_left;
                $new_string['top'] = $string['top'] + ($index * $line_height);
                $new_string['string'] = $part;
                $new_strings[] = $new_string;
            }
        }
    }

    if ( $new_strings )
        $strings = $new_strings;

In this case, each line of $ is an array with some information about how and what to print. Hope that helps someone.

Answer 1

You can use the stil / gd-text class. Disclaimer: I am the author.

<?php
use GDText\Box;
use GDText\Color;

$img = imagecreatefromjpeg('image.jpg');

$textbox = new Box($img);
$textbox->setFontSize(12);
$textbox->setFontFace('arial.ttf');
$textbox->setFontColor(new Color(0, 0, 0));
$textbox->setBox(
    50,  // distance from left edge
    50,  // distance from top edge
    200, // textbox width
    100  // textbox height
);

// now we have to align the text horizontally and vertically inside the textbox
$textbox->setTextAlign('center', 'top');
// it accepts multiline text
$textbox->draw("This is\na string of text");

Demonstration:

Answer 2

, imagettfbbox, , , , , .

function imagettftext_cr(&$im, $size, $angle, $x, $y, $color, $fontfile, $text)
{
  $bbox = imagettfbbox($size, $angle, $fontfile, $text);
  $dx = ($bbox[2]-$bbox[0])/2.0 - ($bbox[2]-$bbox[4])/2.0;
  $dy = ($bbox[3]-$bbox[1])/2.0 + ($bbox[7]-$bbox[1])/2.0;
  $px = $x-$dx;
  $py = $y-$dy;
  return imagettftext($im, $size, $angle, $px, $py, $color, $fontfile, $text);
}

: PHP...

. , , $angle . $width - .

function wrap($fontSize, $angle, $fontFace, $string, $width)
{
  $ret = "";
  $arr = explode(' ', $string);
  foreach ( $arr as $word )
  {
    $teststring = $ret.' '.$word;
    $testbox = imagettfbbox($fontSize, $angle, $fontFace, $teststring);
    if ( $testbox[2] > $width ){
      $ret.=($ret==""?"":"\n").$word;
    } else {
      $ret.=($ret==""?"":' ').$word;
    }
  }
  return $ret;
}

Answer 3

You can use the excellent gd-text library . If you use a composer, an example would be:

<?php
require __DIR__.'/../vendor/autoload.php';

use GDText\Box;

$im = imagecreatetruecolor(500, 500);
$backgroundColor = imagecolorallocate($im, 0, 18, 64);
imagefill($im, 0, 0, $backgroundColor);

$box = new Box($im);
$box->setFontFace(__DIR__.'/Pacifico.ttf'); // http://www.dafont.com/pacifico.font
$box->setFontSize(80);
$box->setFontColor([255, 255, 255]);
$box->setTextShadow([0, 0, 0, 50], 0, -2);
$box->setLeading(0.7);
$box->setBox(20, 20, 460, 460);
$box->setTextAlign('center', 'center');
$box->draw("Pacifico");

header("Content-type: image/png");
imagepng($im);

Answer 4

Get the length of the string (strlen) and the average width of each letter, multiply the result of strlen by the average width, and then subtract from its horizontal position.

$text="center this";
$h=50;
$h=(strlen($text)*15)-$h;

Tell me if this works because I have never tried this.