Php/docs/function.imageftbbox
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
imageftbbox
( float $size
, float $angle
, string $fontfile
, string $text
[, array $extrainfo
] ) : array
This function calculates and returns the bounding box in pixels for a FreeType text.
参数
size字体的尺寸，单位：点（磅）。
angleAngle in degrees in which
textwill be measured.fontfileThe name of the TrueType font file (can be a URL). Depending on which version of the GD library that PHP is using, it may attempt to search for files that do not begin with a leading '/' by appending '.ttf' to the filename and searching along a library-defined font path.
textThe string to be measured.
extrainfo- {|
|+ Possible array indexes for
extrainfo! Key ! Type ! Meaning |- |linespacing| float | Defines drawing linespacing |}
返回值
imageftbbox() returns an array with 8 elements representing four points making the bounding box of the text:
| 0 | lower left corner, X position |
| 1 | lower left corner, Y position |
| 2 | lower right corner, X position |
| 3 | lower right corner, Y position |
| 4 | upper right corner, X position |
| 5 | upper right corner, Y position |
| 6 | upper left corner, X position |
| 7 | upper left corner, Y position |
The points are relative to the text regardless of the
angle, so "upper left" means in the top left-hand
corner seeing the text horizontally.
范例
Example #1 imageftbbox() example
<?php// Create a 300x150 image$im = imagecreatetruecolor(300, 150);$black = imagecolorallocate($im, 0, 0, 0);$white = imagecolorallocate($im, 255, 255, 255);// Set the background to be whiteimagefilledrectangle($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, $font, 'The PHP Documentation Group');// Output to browserheader('Content-Type: image/png');imagepng($im);imagedestroy($im);?>
注释
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.
|
