RTL processing

Presentational forms

The presentational form selected when rendering specific RTL characters may be influenced by the position of the character within a word. The rendering of presentational forms for the following RTL code points is supported:

Code Name
U+0621 ARABIC LETTER HAMZA
U+0622 ARABIC LETTER ALEF WITH MADDA ABOVE
U+0623 ARABIC LETTER ALEF WITH HAMZA ABOVE
U+0624 ARABIC LETTER WAW WITH HAMZA ABOVE
U+0625 ARABIC LETTER ALEF WITH HAMZA BELOW
U+0626 ARABIC LETTER YEH WITH HAMZA ABOVE
U+0627 ARABIC LETTER ALEF
U+0628 ARABIC LETTER BEH
U+0629 ARABIC LETTER TEH MARBUTA
U+062A ARABIC LETTER TEH
U+062B ARABIC LETTER THEH
U+062C ARABIC LETTER JEEM
U+062D ARABIC LETTER HAH
U+062E ARABIC LETTER KHAH
U+062F ARABIC LETTER DAL
U+0630 ARABIC LETTER THAL
U+0631 ARABIC LETTER REH
U+0632 ARABIC LETTER ZAIN
U+0633 ARABIC LETTER SEEN
U+0634 ARABIC LETTER SHEEN
U+0635 ARABIC LETTER SAD
U+0636 ARABIC LETTER DAD
U+0637 ARABIC LETTER TAH
U+0638 ARABIC LETTER ZAH
U+0639 ARABIC LETTER AIN
U+063A ARABIC LETTER GHAIN
U+0641 ARABIC LETTER FEH
U+0642 ARABIC LETTER QAF
U+0643 ARABIC LETTER KAF
U+0644 ARABIC LETTER LAM
U+0645 ARABIC LETTER MEEM
U+0646 ARABIC LETTER NOON
U+0647 ARABIC LETTER HEH
U+0648 ARABIC LETTER WAW
U+0649 ARABIC LETTER ALEF MAKSURA
U+064A ARABIC LETTER YEH
U+067E ARABIC LETTER PEH
U+0686 ARABIC LETTER TCHEH
U+0698 ARABIC LETTER JEH
U+06A9 ARABIC LETTER KEHEH
U+06AD ARABIC LETTER NG
U+06AF ARABIC LETTER GAF
U+06BE ARABIC LETTER HEH DOACHASHMEE
U+06C1 ARABIC LETTER HEH GOAL
U+06CC ARABIC LETTER FARSI YEH
U+06D0 ARABIC LETTER E
U+06D2 ARABIC LETTER YEH BARREE

Diacritics

Diacritics declared using combining characters are horizontally centred and positioned vertically above or below the adjacent base character. Font specific anchors are not applied when positioning diacritics.

Diacritics are always processed in the order in which they are declared within the source content. Canonical ordering of combining character sequences is not applied.

Ligatures

Ligatures for the following lām + alif Unicode sequences are automatically applied:

Sequence Ligature
U+0644, U+0642 ARABIC LIGATURE LAM WITH ALEF WITH MADDA ABOVE
U+0644, U+0623 ARABIC LIGATURE LAM WITH ALEF WITH HAMZA ABOVE
U+0644, U+0625 ARABIC LIGATURE LAM WITH ALEF WITH HAMZA BELOW
U+0644, U+0627 ARABIC LIGATURE LAM WITH ALEF
U+0644,U+0627,U+0653 ARABIC LIGATURE LAM WITH ALEF WITH MADDA ABOVE
U+0644,U+0627,U+0654 ARABIC LIGATURE LAM WITH ALEF WITH HAMZA ABOVE
U+0644,U+0627,U+0655 ARABIC LIGATURE LAM WITH ALEF WITH HAMZA BELOW

Ligatures for the following Unicode sequences are automatically applied:

Sequence Ligature
U+064C, U+0651 ARABIC LIGATURE SHADDA WITH DAMMATAN
U+064D, U+0651 ARABIC LIGATURE SHADDA WITH KASRATAN
U+0651, U+064E ARABIC LIGATURE SHADDA WITH FATHA
U+064F, U+0651 ARABIC LIGATURE SHADDA WITH DAMMA
U+0650, U+0651 ARABIC LIGATURE SHADDA WITH KASRA
U+0650, U+0670 ARABIC LIGATURE SHADDA WITH SUPERSCRIPT ALEF

Paragraph alignment

The alignment of RTL content within paragraphs is determined by the paragraph alignment. Automatic stretching or compression of characters in order to justify RTL content is not supported.