1.4.4 Character Clusters

A character cluster is a collection of alphabetic characters forming a single word or syllable.

A Hebrew character cluster can contain characters and diacritics, though diacritics are not often used.

Character clusters are integral to written text in Thai. A Thai character cluster consists of up to four parallel lines:

• Base line of consonant, vowel, or symbol

• Lower line of lower vowel or diacritic

• Upper line of upper vowel or diacritic

• Line above the upper line for tone marks and upper diacritics

One or more elements may change shape in the presence of other elements. In the Thai language engine, a character cluster occupies one display cell. Depending on the composition, one display cell can contain up to three input characters, as shown in Figure 1-5.

Figure 1-5 Thai-language character cluster