Hyphenation
(mPDF ≥ 2.5)
Hyphenation was changed in mPDF 5.7 to support the CSS property hyphens (cf.)
The CSS property hyphens is supported on block elements (e.g. <div>),
inline elements (e.g. <span>) and <td>/<th>.
hyphens: none|manual|auto
Default: manual
The default can be changed by altering defaultCSS
configuration variable;
Values:
none- Words are not broken at line breaks, even if characters inside the word suggest line break points.manual- Words are only broken at line breaks where there are characters inside the word that suggest line break opportunities. Characters can be explicit or conditional.auto- Words can be broken at appropriate hyphenation points, as determined by characters inside the word, resources. SHY (i.e. soft-hyphen) inside the word take priority over hyphenation points determined by other resources.
Soft hyphens
The soft-hyphen character (U+00AD or ­) and the <wbr> tag (from mPDF 5.7) are supported in
WriteHTML().
Automatic hyphenation
Automatic hyphenation is set using CSS:
hyphens: auto;
Automatic hyphenation is based on the commonly used TeX algorithm and requires pattern files for each language. The following languages are supplied with mPDF 2.5:
| Language | $SHYlang variable |
|---|---|
| English | 'en' (Default) |
| German | 'de' |
| Spanish | 'es' |
| Finnish | 'fi' |
| French | 'fr' |
| Italian | 'it' |
| Dutch | 'nl' |
| Portuguese | 'pl' |
| Russian | 'ru' |
| Swedish | 'sv' |
A pattern file for each language is found in the directory [mpdf root]/data/patterns/ and the
configuration variable
$SHYlanguages needs to be updated if any additions are made.
The $SHYlang variable specifies which language to use for the automatic hyphenation from
the $SHYlanguages array.
Pattern checking can be fine-tuned by four variables if required:
| mPDF variable | Default value | Description |
|---|---|---|
| $SHYleftmin | 2 |
Minimum number of characters allowed to the left of a hyphen. |
| $SHYrightmin | 2 |
Minimum number of characters allowed to the right of a hyphen. |
| $SHYcharmin | 2 |
Minimum number of characters of words to be checked. |
| $SHYcharmax | 10 |
Maximum number of characters in a pattern used for pattern checking (10 usually is more than enough). This is NOT the maximum length of words to be checked. |
Examples
<?php
$mpdf = new \Mpdf\Mpdf();
$mpdf->SHYlang = 'fr';
$mpdf->SHYleftmin = 3;
$mpdf->WriteHTML('Le long texte....');
$mpdf->Output();
Hyphenation Dictionary
If automatic hyphenation does not recognise a particular word, you can add words to a dictionary file with your own
hyphenation. Edit the file [path to mpdf]/patterns/dictionary.txt and add a new line for each word, marking the
possible hyphenations with a forward slash. You can mark more than one place for each word e.g.
dis/es/tab/lish/men/tar/i/an/ism
See Also
- SHYlang - Specify the language to use for automatic hyphenation
