Joining Type
Joining Type is a character classification that determines how a letter connects to adjacent letters within a word, primarily for cursive scripts like Arabic, Syriac, and N’Ko. It assigns each character one of several values: Right Joining (connects only to the left), Left Joining (connects only to the right), Dual Joining (connects on both sides), Non Joining (never connects), or Transparent (affects joining but is not itself visible as a connector, such as diacritics). Additionally, Join Causing characters force a connection between neighbors, while the values also handle special cases like Arabic-Indic digits. This property is essential for correct text shaping, enabling renderers to select appropriate contextual letterforms (initial, medial, final, or isolated) based on the joining behavior of surrounding characters.
- Abbr
- R
- Count
- 153
Right Joining is used for characters that connect only to the preceding character, not the following one.
- Abbr
- L
- Count
- 27
Left Joining is a category for characters that connect only to the following character, not the preceding one, in cursive scripts.
- Abbr
- D
- Count
- 615
Dual Joining is when a character connects on both sides, allowing it to link with preceding and following letters in cursive scripts like Arabic.
- Abbr
- C
- Count
- 7
Join Causing is a value that makes a character connect to both neighboring letters, acting like a dual-joiner in scripts such as Arabic.
- Abbr
- U
- Count
- 307284
Non-Joining is a character classification indicating that a letter never connects to adjacent letters in cursive scripts like Arabic.
- Abbr
- T
- Count
- 2255
Transparent is a joining type where characters do not connect to adjacent letters, acting as invisible separators in cursive scripts.