<?php
/*
 * Overprinting text:
 * Create text which will overprint other page contents instead of knocking
 * it out
 *
 * Create an extended graphics state with the options
 * "overprintfill=true overprintmode=1".
 *
 * Required software: PDFlib/PDFlib+PDI/PPS 10
 * Required data: none
 */

/* This is where the data files are. Adjust as necessary. */
$searchpath = dirname(__FILE__,3)."/input";
$outfile = "";
$title = "Overprinting Text";

try {
    $p = new pdflib();

    $p->set_option("searchpath={" . $searchpath . "}");

    /* This means we must check return values of load_font() etc. */
    $p->set_option("errorpolicy=return");

    if ($p->begin_document($outfile, "") == 0)
        throw new Exception("Error: " . $p->get_errmsg());

    $p->set_info("Creator", "PDFlib Cookbook");
    $p->set_info("Title", $title );

    /* Start page */
    $p->begin_page_ext(400, 300, "");
    
    /* Draw a red background rectangle */
    $p->setcolor("fill", "cmyk", 0, 1, 1, 0);
    $p->rect(0, 0, 400, 300);
    $p->fill();
    
    /* Save the current graphics state */
    $p->save();
    
    /* Create an extended graphics state */
    $gstate = $p->create_gstate("overprintfill overprintmode=1");
    
    /* Apply the extended graphics state */
    $p->set_gstate($gstate);
    
    /* Show some text which will overprint other page contents according to
     * the graphics state set
     */
    $fontopts = "fontname=NotoSerif-Bold fontsize=36";
    
    $p->setcolor("fill", "cmyk", 0, 0, 0, 1);
    $p->fit_textline("overprinting text", 20, 200, $fontopts);
    
    /* Restore the current graphics state */
    $p->restore();
           
    /* Show some text. It will not be overprinting since the old graphics
     * state has been restored with no overprinting set.
     */
    $p->setcolor("fill", "cmyk", 0, 0, 0, 1);
    $p->fit_textline("text not overprinting", 20, 100, $fontopts);
    
    $p->end_page_ext("");

    $p->end_document("");

    $buf = $p->get_buffer();
    $len = strlen($buf);

    header("Content-type: application/pdf");
    header("Content-Length: $len");
    header("Content-Disposition: inline; filename=overprinting_text.pdf");
    print $buf;


} catch (PDFlibException $e){
    echo("PDFlib exception occurred:\n" .
        "[" . $e->get_errnum() . "] " . $e->get_apiname() .
        ": " . $e->get_errmsg() . "\n");
    exit(1);
} catch (Throwable $e) {
    echo("PHP exception occurred: " . $e->getMessage() . "\n");
    exit(1);
}
$p = 0;
?>