THotPDF Tibetan, Mongolian, and Syriac Shaping Methods

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THotPDF API reference

THotPDF Methods Auto Shaping GSUB

Documents the current non-Arabic complex-script shaping helpers for Tibetan, Mongolian, and Syriac

Delphi syntax

function TibetanShapeToGIDs(const S: UnicodeString): TGSUBLookupArray;

function ApplyTibetanShaping(const S: UnicodeString): UnicodeString;

function ApplySyriacGSUBPositional(const S: UnicodeString): UnicodeString;

function ApplyMongolianGSUBPositional(const S: UnicodeString): UnicodeString;

function GetSyriacJoiningClass(CP: Cardinal): Integer;

function GetSyriacPosition(const Wide: UnicodeString; Index: Integer): Integer;

function GetMongolianJoiningClass(CP: Cardinal): Integer;

function GetMongolianPosition(const Wide: UnicodeString; Index: Integer): Integer;

Covered APIs

API	Usage notes
`TibetanShapeToGIDs`	Returns a Tibetan shaped glyph-ID sequence without emitting PDF text
`ApplyTibetanShaping`	Applies Tibetan GSUB shaping and maps shaped glyph IDs through synthetic codepoints for text output
`ApplySyriacGSUBPositional`	Applies Syriac joining-position analysis and font positional GSUB features
`ApplyMongolianGSUBPositional`	Applies Mongolian joining-position analysis and font positional GSUB features
`GetSyriacJoiningClass`	Returns the Unicode joining class used by Syriac position resolution
`GetSyriacPosition`	Resolves an item in a Syriac run to isolated, initial, medial, or final form
`GetMongolianJoiningClass`	Returns the joining class used by Mongolian position resolution, including transparent controls
`GetMongolianPosition`	Resolves an item in a Mongolian run to the positional form requested from GSUB
`AutoShapeSyriac`	Opt-in property that connects Syriac producer-side shaping to text output whilst preserving byte-stable defaults
`sfTibetanShaping`	Enables Tibetan GSUB shaping and synthetic-codepoint emission for shaped Tibetan glyph IDs
`sfMongolianShaping`	Enables Mongolian positional-form shaping through joining analysis and font GSUB lookups

Usage notes

Tibetan uses GSUB feature passes for subjoined consonants and vowels. Syriac and Mongolian use joining-class and position walkers to select font-defined init, medi, fina, or isol forms. AutoShapeSyriac and the sfTibetanShaping/sfMongolianShaping flags connect these helpers to text output