php imagettftext letter spacing

Question

Does anybody have a function that draws a ttf string (imagettftext) with specified letter spacing?

I cannot find any build-in GD function so I think that it should be done letter by letter adding some constant width.

Maybe someone have such function already :)

ps. the best font will be arial.ttf

Answer 1

Try this function:

$image = imagecreatetruecolor(500,200);
$text = "Text to print";
$text_color=imagecolorallocate($image,255,255,255);
$font_size = 18;
$space = 8;
$font = "path_to_font/arial.ttf";
$x=20;
$y=20;
for ($i = 0; $i <strlen($text); $i++){
   $arr = imagettftext ($image, $font_size,0, $x, $y, $text_color, $font, $text{$i});
   $x = $arr[4]+$space;
}
imagejpeg($image);
destroyimage($image);

Answer 2

I know this was answered a while back, but I needed a solution that had letter spacing and maintained the angular offsets.

I modified radzi's code to accomplish this:

function imagettftextSp($image, $size, $angle, $x, $y, $color, $font, $text, $spacing = 0)
{        
    if ($spacing == 0)
    {
        imagettftext($image, $size, $angle, $x, $y, $color, $font, $text);
    }
    else
    {
        $temp_x = $x;
        $temp_y = $y;
        for ($i = 0; $i < strlen($text); $i++)
        {
            imagettftext($image, $size, $angle, $temp_x, $temp_y, $color, $font, $text[$i]);
            $bbox = imagettfbbox($size, 0, $font, $text[$i]);
            $temp_x += cos(deg2rad($angle)) * ($spacing + ($bbox[2] - $bbox[0]));
            $temp_y -= sin(deg2rad($angle)) * ($spacing + ($bbox[2] - $bbox[0]));
        }
    }
}

Answer 3

function imagettftextSp($image, $size, $angle, $x, $y, $color, $font, $text, $spacing = 0)
{        
    if ($spacing == 0)
    {
        imagettftext($image, $size, $angle, $x, $y, $color, $font, $text);
    }
    else
    {
        $temp_x = $x;
        for ($i = 0; $i < strlen($text); $i++)
        {
            $bbox = imagettftext($image, $size, $angle, $temp_x, $y, $color, $font, $text[$i]);
            $temp_x += $spacing + ($bbox[2] - $bbox[0]);
        }
    }
}

and the call:

imagettftextSp($image, 30, 0, 30, 30, $black, 'arial.ttf', $text, 23);

Function parameters order meets standard imagettftext parameters order, and the last parameter is optional $spacing parameter. If not set or the passed value is 0, the kerning / letter spacing is not set.

Answer 4

GD doesn't support kerning, so you'll have to do it manually. Personally, I wrote a function that would write each letter separately. I can't find it right now, but it's something along the lines of:

function drawText(&$image, $text, $fgColor, $font, $fgColor, 
                   $fontSize = 14, $kerning = 0, $x = 0, $y = 0) {
    $letters = explode('', $text);

    foreach ($letters as $n => $letter) {
        $bbox = imagettftext($image, $fontSize, 0, $x, $y, $fgColor, $font, $letter);
        $x += $bbox[2] + $kerning;
    }
}

Answer 5

Just to complete pidalia's answer (which is the best) to avoid some trouble with special char (like "é" or "à")

static function imagettftextSp($image, $size, $angle, $x, $y, $color, $font, $text, $spacing = 0) {
    if ($spacing == 0) {
        imagettftext($image, $size, $angle, $x, $y, $color, $font, $text);
    } else {
        $temp_x = $x;
        $temp_y = $y;
        //to avoid special char problems
        $char_array = preg_split('//u',$text, -1, PREG_SPLIT_NO_EMPTY);
        foreach($char_array as $char) {
            imagettftext($image, $size, $angle, $temp_x, $temp_y, $color, $font, $char);
            $bbox = imagettfbbox($size, 0, $font, $char);
            $temp_x += cos(deg2rad($angle)) * ($spacing + ($bbox[2] - $bbox[0]));
            $temp_y -= sin(deg2rad($angle)) * ($spacing + ($bbox[2] - $bbox[0]));
        }
    }
}