ASS_FEATURE_WRAP_UNICODE constant
int
const ASS_FEATURE_WRAP_UNICODE
Break lines according to the Unicode Line Breaking Algorithm. If the track language is set, some additional language-specific tweaks may be applied. Setting this enables more breaking opportunities compared to classic ASS. However, it is still possible for long words without breaking opportunities to cause overfull lines. This is incompatible with VSFilter and disabled by default.
This feature may be unavailable at runtime if libass was compiled without libunibreak support.
Implementation
static const int ASS_FEATURE_WRAP_UNICODE = 3;