tcpdf and locales getnumlines wrong count
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I found annoying error with TCPDF library. Hope you know how help me. I use obj->getNumLines method to calculate how many lines has my text. It works all good in most cases but unfortunatelly not always.I use UTF8 encoding and I use many local signs (I'm from poland and we have a lot of such signs). getNumLines sometimes returns i.e. 5 although multicell displays 6 lines of text. 

In my research I found that:

    $font = $pdf->addTTFfont('/fonts/calibri.ttf', '', '', 32);
    $pdf->setFont($font, '', 13)
    $string = 'zażółć gęślą jaźń'; (repeated many times)
    echo $pdf->getNumLines($string, 0);

It prints to the screen different (smaller) number than multicell actually returns lines to the pdf file. I use custom fonts as you can see above, margins are not changed during the code.

Does anybody has idea what is wrong or how to fix it?

