PDF_setfont()

(PHP 4 >= 4.0.5, PECL pdflib >= 1.0.0)

Set font

说明

PDF_setfont(resource $pdfdoc,int $font,float $fontsize): bool

Sets the current font in the specified$fontsize, using a$fonthandle returned by PDF_load_font().成功时返回TRUE，或者在失败时返回FALSE。

Here is a simple function to ease changing fonts in your PDF.
function pdf_font($pdf,$size,$face='arial')
{
  //Set the path 
  $path=$_SERVER['DOCUMENT_ROOT'];
  ${$face} = $face."=$path/fonts/".$face.".ttf";
  pdf_set_parameter($pdf, 'FontOutline',${$face});
    
  $font=pdf_findfont($pdf,$face,"host",0);
  
  pdf_setfont($pdf,$font,$size);
}

Note that pdf_setfont (this function) and pdf_set_font (a deprecated function) are different. I spent a while trying to figure out why my code wasn't working; it turns out I'd included the extra underscore by accident...

Note that core font Helvetica-Bold does not accept font sizes>12 .
This probably affects other core fonts.

For those who are looking 
the PDF core fonts Are
Courier,Courier-Bold,Courier-Oblique,Courier-BoldOblique,
Helvetica,Helvetica-Bold,Helvetica-Oblique,Helvetica-BoldOblique,
Times-Roman,Times-Bold,Times-Italic,Times-BoldItalic,
Symbol,ZapfDingbats

To anyone who is trying to add extra FONTS to work with PHP and pdflib.
Take a look at: ftp://ftp.adobe.com/pub/adobe/type/win/all/afmfiles/ - This is collection of fonts already converted to AFM. There are thousands of fonts. What I am doing is downloading everything, and then I will grep my way through the directories to find what I am looking for.
Another tip: to get the pdflib.upr file working with your fonts add:
putenv("PDFLIBRESOURCE=/dir/where/the/file/is/fonts/pdflib.upr");
on the beginning of your php script. And make sure you change the Font Definition entry on your pdflib.upr file as well. It needs to point to the directory where the .afm files are.

There is also another encoding called 'host'. in the pdflib test examples, they say:
" We don't want to use metrics files for the sample, and therefore stick to host encoding. For this reason the sample text (which uses German special characters) must be platform-specific. Both flavors only differ in the special characters."