Do you use UTF-8? Text has to be given in UTF-8. If not, it may cause some troubles by the encoding detection or the glyph selection in freetype (esp. when the font only has utf-8).

Hello,
thank you for the answer.

I thought it is utf-8, because the function mb_detect_encoding gives utf-8.

After your answer i testet it with
function is_utf8($string) {
   
    // From http://w3.org/International/questions/qa-forms-utf-8.html
    return preg_match('%^(?:
          [\x09\x0A\x0D\x20-\x7E]            # ASCII
        | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
        |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
        | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
        |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
        |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
        | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
        |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
    )*$%xs', $string);
   
}

and this gives 0, also not utf-8. :-(

I quickly made this test:
I use char("???") it gives 228 which is correct ISO... "?",
then utf8_encode("???") and testing with the function is_utf8 gives 1, also the string seems now to be utf-8 encoded.
If i now send this converted string to "imagettftext" the result is
again one square and ?.
Possibly i made something wrong, because i am not an php programmer.  
But for me it seems, that the code of two characters become one utf-8 character. 

I am making more tests next days an then i tell the results.
If someone can tell some futher tests, i will do them an post the results.

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