ClibPDF lets you create PDF documents with PHP. It is available for download from FastIO, but requires that you purchase a license for commercial use. ClibPDF functionality and API are similar to PDFlib.
This documentation should be read alongside the ClibPDF manual since it explains the library in much greater detail.
Currently this handle is not used internally since ClibPDF does not support the creation of several PDF documents at the same time. Actually, you should not even try it, the results are unpredictable. I can't oversee what the consequences in a multi threaded environment are. According to the author of ClibPDF this will change in one of the next releases (current version when this was written is 1.10). If you need this functionality use the pdflib module.
A nice feature of ClibPDF (and PDFlib) is the ability to create the pdf document completely in memory without using temporary files. It also provides the ability to pass coordinates in a predefined unit length. (This feature can also be simulated by pdf_translate() when using the PDFlib functions.)
Another nice feature of ClibPDF is the fact that any page can be modified at any time even if a new page has been already opened. The function cpdf_set_current_page() allows to leave the current page and presume modifying an other page.
Most of the functions are fairly easy to use. The most difficult part is probably creating a very simple PDF document at all. The following example should help you to get started. It creates a document with one page. The page contains the text "Times-Roman" in an outlined 30pt font. The text is underlined.
The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.
Example 1. Simple ClibPDF Example
The pdflib distribution contains a more complex example which creates a series of pages with an analog clock. Here is that example converted into PHP using the ClibPDF extension:
Example 2. pdfclock example from pdflib 2.0 distribution
See also the PDFlib extension documentation.