Welcome to a quick tutorial on how to write multiple lines text with PHP GD. So you have probably messed with GD to write some text, only to realize that there is no way to “automatically break into multiple lines”.
imagettftext()
many times to write text at different positions.Yes, it’s a real pain. So here’s a quick example of how I “automated” the line breaks – Read on!
ⓘ I have included a zip file with all the source code at the start of this tutorial, so you don’t have to copy-paste everything… Or if you just want to dive straight in.
TABLE OF CONTENTS
DOWNLOAD & NOTES
Firstly, here is the download link to the example code as promised.
QUICK NOTES
- Edit
multi-lines.php
, change$font
to your own. - Just run
multi-lines.php
in the browser or command line – It will write text ondemo.webp
, and save it towritten.webp
.
EXAMPLE CODE DOWNLOAD
Click here to download all the example source code, I have released it under the MIT license, so feel free to build on top of it or use it in your own project.
PHP GD WRITE MULTIPLE LINES
All right, let us now get into the example of writing multiple lines text with PHP GD.
PART 1) TEXT & FONT SETTINGS
// (A) SETTINGS
// (A1) FONT & TEXT SETTINGS
$font = "C:/Windows/Fonts/lucon.ttf"; // CHANGE TO YOUR OWN!
$fontSize = 24;
$fontColor = [255, 255, 255];
$txt = "TAKE A BREAK. IT'S TIME TO DRINK A BUBBLE TEA!";
$maxChar = 13; // max characters per line
$maxLines = 5; // max lines
$offsetX = 3; // "character spacing offset"
$offsetY = 20; // "line height offset"
First, we begin with a whole bunch of settings. Let’s run through them quickly:
$font $fontSize $fontColor $txt
Don’t think these need any explanation, but I will recommend using monospace fonts. They are much more “predictable” and you can better plan the “max allowed text space on the image”.$maxChar
Maximum number of characters per line. In this example,$txt
will break into 4 lines.$maxLines
If the “broken into lines”$txt
has more lines than this, don’t generate the image… It will end up looking funky.$offsetX
“Letter spacing”. Yes, GD does not have a native function to control the space between each character, we have to manually set the spacing.$offsetY
“Line height”. Again, GD does not have a native function to control the “line spacing”.
PART 2) DRAW SETTINGS
// (A2) DRAW SETTINGS
$angle = 0; // if you want slanted text
$x = 30; $y = 100; // starting position
$quality = 90; // image quality
$source = "demo.webp";
$target = "written.webp";
$angle
Leave this as 0, unless you want slanted text.$x $y
The starting position of the first character.$quality
Output image quality, 0 to 100.$source $target
Source image (above), and where to save the processed image.
PART 3) BREAK TEXT INTO LINES
// (B) AUTO-BREAK TEXT INTO LINES
$tmpX = explode(" ", $txt);
$tmpY = "";
$lines = [];
foreach ($tmpX as $word) {
if ($tmpY=="") { $tmpY .= $word; }
else {
if (strlen("$tmpY $word") <= $maxChar) { $tmpY = "$tmpY $word"; }
else {
$lines[] = $tmpY;
$tmpY = $word;
}
}
}
$lines[] = $tmpY;
if (count($lines)>$maxLines) { exit("'$txt' is too long!"); }
Not going to explain this line-by-line (pun intended), but it essentially breaks $txt
into an array $lines
; Following the rule that only $maxChars
characters are allowed per line, and up to $maxLines
lines are allowed.
P.S. In this example, $txt
will break down into $lines = ["TAKE A BREAK.", "IT'S TIME TO", "DRINK A", "BUBBLE TEA"]
PART 4) DRAW LINES ONTO IMAGE
// (C) DRAW LINES ONTO IMAGE
// CREDITS : https://stackoverflow.com/questions/6926613/php-imagettftext-letter-spacing
$img = imagecreatefromwebp($source);
$color = imagecolorallocate($img, ...$fontColor);
foreach ($lines as $line) {
$tmpX = $x;
for ($j=0; $j<strlen($line); $j++) {
$bbox = imagettftext($img, $fontSize, $angle, $tmpX, $y, $color, $font, $line[$j]);
$tmpX += $offsetX + ($bbox[2] - $bbox[0]);
}
$y += $fontSize + $offsetY;
}
Now that we have broken $txt
into $lines
, we do the very obvious thing – Loop through $lines
and draw it line-by-line. What is happening here:
foreach ($lines as $line) { DRAW LINE; $y += $fontSize + $offsetY; }
- Yes, that entire
for ($j...)
part is literally drawing character by character of each line. Because there is no way to define “letter-spacing”, we have to do it manually. Credits to this post on StackOverflow.
PART 5) SAVE PROCESSED IMAGE
// (D) SAVE COMPLETE IMAGE
imagewebp($img, $target, $quality);
echo "OK";
Lastly, just save the processed image. The end. Thankfully.
EXTRA BITS & LINKS
That’s all for the tutorial, and here is a small section on some extras and links that may be useful to you.
LINKS & REFERENCES
- GD – Official PHP Manual
- PHP Add Text To Image – Code Boxx
THE END
Thank you for reading, and we have come to the end. I hope that it has helped you to better understand, and if you want to share anything with this guide, please feel free to comment below. Good luck and happy coding!