imageftbbox
(PHP 4 >= 4.0.7, PHP 5, PHP 7)
imageftbbox — 给出一个使用 FreeType 2 字体的文本框
说明
$size ,
float $angle ,
string $fontfile ,
string $text [,
array $extrainfo ] ) :
array
This function calculates and returns the bounding box in pixels for a FreeType text.
参数
-
size -
字体的尺寸。根据 GD 的版本，为像素尺寸（GD1）或点（磅）尺寸（GD2）。
-
angle -
Angle in degrees in which
textwill be measured. -
fontfile -
The name of the TrueType font file (can be a URL). Depending on which version of the GD library that PHP is using, it may attempt to search for files that do not begin with a leading '/' by appending '.ttf' to the filename and searching along a library-defined font path.
-
text -
The string to be measured.
-
extrainfo -
Possible array indexes for extrainfoKey Type Meaning linespacing float Defines drawing linespacing
返回值
imageftbbox() 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.
范例
Example #1 imageftbbox() example
<?php
// Create a 300x150 image
$im = imagecreatetruecolor(300, 150);
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);
// Set the background to be white
imagefilledrectangle($im, 0, 0, 299, 299, $white);
// Path to our font file
$font = './arial.ttf';
// First we create our bounding box
$bbox = imageftbbox(10, 0, $font, 'The PHP Documentation Group');
// This is our cordinates for X and 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, $black, $font, 'The PHP Documentation Group');
// Output to browser
header('Content-Type: image/png');
imagepng($im);
imagedestroy($im);
?>
注释
Note: 此函数需要 GD 2.0.1 或更高版本(推荐 2.0.28 及更高版本)。
Note: 此函数仅在 PHP 编译时加入 freetype 支持时有效（--with-freetype-dir=DIR ）。
更新日志
| 版本 | 说明 |
|---|---|
| 4.3.5 | extrainfo was made optional. |
