php imagettftext letter spacing
Does anybody have a function that draws a ttf string (imagettftext) with specified letter spacing?
I cannot find any build-in GD f开发者_运维知识库unction 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
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 $spacing parameter. If not set or the passed value is 0, the kerning / letter spacing is not set.
I know this was answered a while back, but I needed a solution that had letter spacing and maintained the angular offsets.
I modified radzi's code to accomplish this:
function imagettftextSp($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] - $bbox[0]));
}
}
}
Just to complete pidalia's answer (which is the best) to avoid some trouble with special char (like "é" or "à")
static function imagettftextSp($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] - $bbox[0]));
}
}
}
GD doesn't support kerning, so you'll have to do it manually. Personally, I wrote a function that would write each letter separately. I can't find it right now, but it's something along the lines of:
function drawText(&$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] + $kerning;
}
}
I have tried all the answers here and none seems to do a decent job. If you draw the bounding box, this is what happens:
Clearly they are not evenly spaced. It appears that the bounding box, returned by imagettftext()
and imagettfbbox()
, only tells you what is drawn. This might seem enough, but it isn't, because of font kerning. This means that even when you say a letter should be draw at (x,y)
, that that will not be one of the coordinates of the bounding box. A correction for kerning is needed.
I botched together this code for horizontal text:
function getBBoxW($bBox)
{
return $bBox[2] - $bBox[0];
}
function imagettftextSpacing($image, $size, $x, $y, $color, $font, $text, $spacing = 0)
{
$testStr = 'test';
$testW = getBBoxW(imagettfbbox($size, 0, $font, $testStr));
foreach (mb_str_split($text) as $char)
{
$fullBox = imagettfbbox($size, 0, $font, $char . $testStr);
imagettftext($image, $size, 0, $x - $fullBox[0], $y, $color, $font, $char);
$x += $spacing + getBBoxW($fullBox) - $testW;
}
}
The results are much better. Note that the $testStr
can have any value.
Here's an example of the result, the first line is normal text, the second line has a negative spacing:
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);
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