PHP 5.6.0RC3 is available

imagepsbbox

(PHP 4, PHP 5)

imagepsbbox给出一个使用 PostScript Type1 字体的文本方框

说明

array imagepsbbox ( string $text , resource $font , int $size )
array imagepsbbox ( string $text , resource $font , int $size , int $space , int $tightness , float $angle )

给出一个使用 PostScript Type1 字体的文本方框。

围绕文本范围的虚拟方框是用从字符度量学中的可用信息来计算的,不幸的是往往和实际上光栅生成的文本的结果有少许不同。如果角度为 0 度,(根据经验)文本在每个方向上都需要多 1 个像素。

参数

text

要写入的文本。

font_index

imagepsloadfont() 所返回的字体资源。

size

size 以像素表示。

space

可以用来改变字体中默认间距的值。此值将被加到通常的值上,可以为负值。 以字符间距单元表示,1 个单元为 1 em-square 的一千分之一。

tightness

tightness 可以控制字符之间的间距。此值将被加到通常字符宽度上,可以为负值。 以字符间距单元表示,1 个单元为 1 em-square 的一千分之一。

angle

angle 以角度表示。

返回值

本函数返回包含有下列单元的数组:

0 左下角的 X 坐标
1 左下角的 Y 坐标
2 右上角的 X 坐标
3 右上角的 Y 坐标

范例

Example #1 imagepsbbox() 用法

<?php
// 创建图像的句柄
$im imagecreatetruecolor(200200);

// 分配颜色
$black imagecolorallocate($im000);
$white imagecolorallocate($im255255255);

// 载入 PostScript 字体
$font imagepsloadfont('font.pfm');

// 设置文本方框
$bbox imagepsbbox('Sample text is simple'$font12);

// 定义 X 和 Y 
$x = ($bbox[2] / 2) - 10;
$y = ($bbox[3] / 2) - 10;

// 字体写入图像
imagepstext($im'Sample text is simple'$font12$black$white$x$y);

// 输出并释放内存
header('Content-type: image/png');

imagepng($im);
imagedestroy($im);
?>

注释

Note: 此函数仅在 PHP 编译时指定了 --with-t1lib[=DIR] 时可用。

参见

  • imagepstext() - 用 PostScript Type1 字体把文本字符串画在图像上

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User Contributed Notes 4 notes

up
0
eikie
6 years ago
I have a given image width and need to render a long string on that image. By using the following function I'm, able to get an array of strings which each will fit into the images width. It might need a lot of CPU time, but it's cool:

// Function to return an Array of Strings
// Arguments: String to be wrapped, maximum width in pixels of each line, font and fontsize
function imgwordwrap($s, $maxWidth, $font, $size) {
  // Make an empty ArrayList
  $a = array();
  $w = 0;    // Accumulate width of chars
  $i = 0;      // Count through chars
  $rememberSpace = 0; // Remember where the last space was
  // As long as we are not at the end of the String
  while ($i < strlen($s)) {
    // Current char
    $c = substr($s, $i, 1);
    $bb = imagepsbbox($c, $font, $size); // calculate width
    $w += abs($bb[3])-abs($bb[1]); // accumulate width
    if ($c == ' ') $rememberSpace = $i; // Are we a blank space?
    if ($w > $maxWidth) {  // Have we reached the end of a line?
      $sub = substr($s,0,$rememberSpace); // Make a substring
            // Chop off space at beginning
            if (substr($sub,0,1)==' ') $sub = substr($sub,1);
      // Add substring to the array
      $a[] = $sub;
      // Reset everything
      $s = substr($s,$rememberSpace);
      $i = 0;
      $w = 0;
    }
    else {
      $i++;  // Keep going!
    }
  }

  // Take care of the last remaining line
  trim($s);
  if (substr($s,0,1)==' ') $s = substr($s,1);
  $a[] = $s;

  return $a;
}
up
0
honza dot bartos at gmail dot com
7 years ago
When using imagepsbbox, keep in mind, that meaning of y-coordinates is slightly different here. Y-coordinates returned by this function are related to the baseline of the text starting at point [0,0]. Positive values represent points ABOVE the baseline, negative values represent points BELOW the baseline. That is why the lower left y-coordinate is always smaller here than the upper right y-coordinate (these two coordinates are actualy values of metrics.descent and metrics.ascent - see T1Lib docs).

So when you want to place some text using coordinates of the top left corner (for example [100,100]), use this:

<?php

$x
= 100;
$y = 100;
$text = "Dodge this";
$fontsize=18;
$font=imagepsloadfont("somefont.pfb");
list(
$lx,$ly,$rx,$ry) = imagepsbbox($text,$font,$fontsize);
imagepstext ($someimage, $text, $font, $fontsize, $somecolor, $somecolor, $x, $y + $ry);

?>

Hope it helps someone, I got stuck with this for a while.
up
0
daniel at dantec dot NO_SPAM dot nl
12 years ago
When using imagepsbbox, you are probably trying to do something like creating a button with text, so that the button is large enough for the text...
Below is a very simple example of making a black button just big enough to display white text on it.

<?php

//if text is no variable set sample text
if (!$text)
   
$text = "This is a sample text";
   
// set the font size
$fontsize=14;

// load the font to use
$font=ImagePsLoadFont("/fonts/ariam___.pfb");

//get the left lower corner and the right upper
list($lx,$ly,$rx,$ry) = imagepsbbox($text,$font,$fontsize,0,0,0);

// calculate the size of the text
$textwidth = $rx - $lx;
$textheight = $ry - $ly;

// make an image 40 pixels wider and 20 pixels higher than the text
$imh = $textheight + 20;
$imw = $textwidth + 40;
$im = imageCreate( $imw, $imh );

//define colors, first color is used as background color!
$black  = ImageColorAllocate ($im, 0, 0, 0);
$white = ImageColorAllocate ($im, 255, 255, 255);

//create the text (with the same parameters as imagepsbbox!)
ImagePSText ($im, "$text", $font, $fontsize, $white, $white, 20, 20,'','','',4);

//send the header
header("Content-type: image/jpeg");

// create the image
ImageJPEG ($im,"",100);

//destroy the image & font to free memory
Imagepsfreefont ( $font );
ImageDestroy ( $im );

?>
up
-1
eikie
6 years ago
in my code below, there is an error!

replace
$w += abs($bb[3])-abs($bb[1]); // accumulate width

with
$w += abs($bb[2])-abs($bb[0]); // accumulate width

also after
$bb = imagepsbbox($c, $font, $size); // calculate width

you can add this line because spaces make odd values...
if ($c == ' ' ) $bb = imagepsbbox('i', $font, $size);
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