THotPDF GSUB Lookup Methods

THotPDF API 参考

本页说明与 GSUB lookup methods 相关的 API 组。类型名、方法名和 Delphi 语法保持不翻译，便于和源码直接对应

Delphi 语法

function GetSingleSubstituteGlyph(InputGID: Word; const FeatureTag: AnsiString): Word;

function GetMultipleSubstituteGlyphs(InputGID: Word; const FeatureTag: AnsiString; var OutGIDs: TGSUBLookupArray): Boolean;

function GetAlternateGlyphCount(InputGID: Word; const FeatureTag: AnsiString): Integer;

function GetAlternateGlyph(InputGID: Word; const FeatureTag: AnsiString; AlternateIndex: Integer): Word;

function ApplyLigatureSubstitution(const InputGIDs: array of Word; StartIndex: Integer; const FeatureTag: AnsiString; out OutGID: Word; out ConsumedCount: Integer): Boolean;

function ApplyContextualSubst(const InputGIDs: array of Word; StartIndex: Integer; const FeatureTag: AnsiString; var OutGIDs: TGSUBLookupArray; out ConsumedLen: Integer): Boolean;

function ApplyReverseChainedContextualSubst(const InputGIDs: array of Word; StartIndex: Integer; const FeatureTag: AnsiString; out OutGID: Word): Boolean;

function ApplyGSUBContextualFeature(const Wide: UnicodeString; const AFeatureTag: AnsiString): UnicodeString;

function ApplyLocalizedForms(const Wide: UnicodeString): UnicodeString;

涵盖的 API

使用说明

在注册合适的 Unicode 字体之后、输出文本之前使用这些 API。如果字体没有声明所需的 OpenType 表，查询会返回安全的无操作结果，或者输出路径回退到更简单的行为

另请参阅: OpenType GSUB Engine GSUB script and language methods ShapingFeatures Subset and mapping methods