For alignment i used this method:
if($align == "center" || $align == "right")
{
$verticaltxtspace = $backwidth - (2 * $posx);
$spacepositions = imagettfbbox($size, $angle, "fonts/verdanaz.ttf", " ");
$spacepx = $spacepositions[4] - $spacepositions[0];
// Split text in lines
$lines = split("[\r][\n]", $text);
for($count = 0; $count < count($lines); $count++)
{
$textpositions = imagettfbbox($size, $angle, "fonts/verdanaz.ttf", $lines[$count]);
$textpx = $textpositions[2] - $textpositions[0];
if($align == "right")
{
$spaces = ($verticaltxtspace - $textpx) / $spacepx;
}
else if($align == "center")
{
$spaces = (($verticaltxtspace - $textpx)/2) / $spacepx;
}
// Add spaces
$line = $lines[$count];
for($i = 0; $i < $spaces; $i++)
{
$line = " " . $line;
}
$lines[$count] = $line;
}
// Create new text of lines
$text = "";
for($count = 0; $count < count($lines); $count++)
{
$text .= $lines[$count] . "\r\n";
}
}
// Draw the shadow text on de shadow
imagettftext($background, $size, $angle, $posx, $posy, $textcolor, "fonts/verdanaz.ttf", $text);
imageftbbox
(PHP 4 >= 4.0.7, PHP 5)
imageftbbox — Devolver la caja circundante de un texto usando fuentes mediante FreeType 2
Descripción
$size
, float $angle
, string $fontfile
, string $text
[, array $extrainfo
] )Esta función calcula y devuelve la caja circundante en píxeles de un texto FreeType.
Parámetros
-
size -
Tamaño de fuente. En función de la versión de GD, se especificará en pixels (GD1) o en puntos (GD2).
-
angle -
Ángulo en grados en el que
textserá medido. -
fontfile -
El nombre de un archivo de fuente TrueType (puede ser una URL). Dependiendo de la versión de la biblioteca GD que esté usando PHP, se intentará buscar archivos que no comiencen con '/' añadiendo '.ttf' al nombre de archivo y buscando en una ruta de biblioteca definida de fuentes.
-
text -
La cadena que va a ser medida.
-
extrainfo -
Posibles índeces de matriz para extrainfoClave Tipo Significado linespacing float Define el espacio entre líneas
Valores devueltos
imageftbbox() devuelve una matriz con 8 elementos que representan cuatro puntos que hacen la caja circundante del texto:
| 0 | esquina inferior izquierda, posición X |
| 1 | esquina inferior izquierda, posición Y |
| 2 | esquina inferior derecha, posición X |
| 3 | esquina inferior derecha, posición Y |
| 4 | esquina superior derecha, posición X |
| 5 | esquina superior derecha, posición Y |
| 6 | esquina superior izquierda, posición X |
| 7 | esquina superior izquierda posición Y |
Los puntos son relativos a text sin importar el ángulo
angle, por lo que "superior izquierda" significa la esquina superior
izquierda, viendo el texto horizontalmente.
Ejemplos
Ejemplo #1 Ejemplo de imageftbbox()
<?php
// Crear una imagen de 300x150
$im = imagecreatetruecolor(300, 150);
$negro = imagecolorallocate($im, 0, 0, 0);
$blanco = imagecolorallocate($im, 255, 255, 255);
// Establecer el fondo a blanco
imagefilledrectangle($im, 0, 0, 299, 299, $blanco);
// Ruta de nuestro archivo de fuente
$fuente = './arial.ttf';
// Priemero creamos nuestra caja circundante
$bbox = imageftbbox(10, 0, $fuente, 'The PHP Documentation Group');
// Estas son nuestras coordenadas para X e Y
$x = $bbox[0] + (imagesx($im) / 2) - ($bbox[4] / 2) - 5;
$y = $bbox[1] + (imagesy($im) / 2) - ($bbox[5] / 2) - 5;
imagefttext($im, 10, 0, $x, $y, $negro, $fuente, 'The PHP Documentation Group');
// Imprimir al navegador
header('Content-Type: image/png');
imagepng($im);
imagedestroy($im);
?>
Notas
Nota: Esta función require GD 2.0.1 o superior (se recomienda 2.0.28 o superior).
Nota: Esta función sólo está disponible si PHP fue compilado con suporte de freetype (--with-freetype-dir=DIR )
Historial de cambios
| Versión | Descripción |
|---|---|
| 4.3.5 |
Ahora extrainfo es opcional.
|
ah... the problem between imageftbbox() and imagefttext() lies in the mirroring of the y-axes.
Below you see, for a font-size 16 the boudingboxes of "b", "p" and "bp":
< b: w=9 h=15
b(0,-1)
b(9,-1)
b(9,-16)
b(0,-16)
< p: w=9 h=16
p(0,4)
p(9,4)
p(9,-12)
p(0,-12)
< bp: w=20 h=20
bp(0,4)
bp(20,4)
bp(20,-16)
bp(0,-16)
If drawing "bp" using imagefttext() at y=0, the the top of "bp" indeed is at y=-16, and the bottom of "bp" at y=4. (Plus or minus a pixel here and there, because at y=0 there actually is a vissible pixel.)
imagettfbbox() returns an array with 8 elements representing four points making the bounding box of the text:
0 lower left corner, X position
1 lower left corner, Y position
2 lower right corner, X position
3 lower right corner, Y position
4 upper right corner, X position
5 upper right corner, Y position
6 upper left corner, X position
7 upper left corner, Y position
The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner seeing the text horizontally.
ImageFTBBox returns a bounding box, not metrics, as some (most?) of the notes above seem to assume. The 8 values it returns specify the 4 corners of this bounding box. So to properly determine the width and height of a string you need to do:
$bbox = ImageFTBBox(...);
$width = abs($bbox[0]) + abs($bbox[2]); // distance from left to right
$height = abs($bbox[1]) + abs($bbox[5]); // distance from top to bottom
Here is a handy example I used to center "dynamic text" onto an image.
Ex. Say you want to center a clients IP Address onto a picture.
$ip=$_SERVER['REMOTE_ADDR'];
$details = imageftbbox($fontsize, 0, $font, $ip, array("linespacing" => 1));
$xcoord = ($imgwidth - $details[4]) / 2; // this will return the x coordinate centered to your specific image. Make sure you set $imgwidth to the width of the image you are using.
imagettftext($image, $fontsize, 0, $xcoord, $ycoord, $fontcolor, $font, $ip);
I noticed that PHP's True Type functions do not allow you to create text blocks with multiple lines that automatically adjust for alignment. I wrote a function that will allow you to generate images with multiple lines, control the alignment, and handle rotation. I hope it helps someone.
There was too much code to paste on this message post so you can grab it off of my webserver. I also created an example page so that you can see the code in action.
Example Page:
http://www.PrintsMadeEasy.com/code_samples/php/text_generation.php
Download the Text file:
http://www.PrintsMadeEasy.com /code_samples/php/text_generation.txt
i've found a work around for this situation
it seems that height is directly proportional to line spacing so you just have to apply the same factor to image height
for example :
$spacing = 0.7;
$params = array("linespacing" => $spacing);
$box = imageftbbox ($size, 0, $font, $text, $params);
$tw=$box[4]-$box[0]; //image width
$th=($box[1]-$box[5])*$spacing; //image height
This function can be used to generate right-aligned text. Just work out how wide the text image is and position it accordingly. Example:
$i_width = 200;
$i_height = 40;
$string = "Hello World!";
$pointsize = 10;
$fontfile = "/usr/local/lib/ttf/Helve.ttf";
$im = imagecreate($i_width, $i_height);
$black = imagecolorallocate ($im, 0, 0, 0);
$white = imagecolorallocate ($im, 255, 255, 255);
$string_size = ImageFtBbox($pointsize, 0, $fontfile, $string, array("linespacing" => 1));
$s_width = $string_size[4];
$s_height = $string_size[5];
ImageFtText($im, $pointsize, 0, $i_width - $s_width - 1, 0 - $s_height, $white, $fontfile, $string, array("linespacing" => 1));
Header ("Content-type: image/png");
ImagePNG ($im);
ImageDestroy ($im);
IF we accept the idea that a bouding box is returned then:
$bbox= imageftbbox ( $size, $angle, $font, $txt);
$width = abs($bbox[4] - $bbox[0]);
$height = abs($bbox[1] - $bbox[5]);
may be a better kind of math. But it depends... You may want to subtract yet another '1' from both the width and the height.
But try drawing a "p" and next try a "d". Their bounding boxes differ 1 px in height. Of course the respective boxes, by imagefttext(), are placed at a different y coordinate. I noticed that if a "p" or a "b" is drawn at (0, 30) the first character of the string actually starts on, fills, the third horizontal pixel. Also: if your image is only 30 pixels in heigth, drawing text at (0, 30) means that the bottoms parts of "p", "q", "y" and alike are somewhere else...
