THotPDF Shaping Subset and ToUnicode Mapping Methods

THotPDF API reference

เอกสารเกี่ยวกับระบบชุดย่อยกริฟฟ์และการเชื่อมโยง ToUnicode ที่ทำให้กริฟฟ์ GID ที่จัดรูปแล้วเรนเดอร์และดึงข้อมูลออกมาได้อย่างถูกต้อง

Delphi syntax

procedure EnableShapingFeatureForSubset(const FeatureTag: AnsiString); overload;

procedure EnableShapingFeatureForSubset(Feature: THPDFShapingFeature); overload;

procedure MarkUnicodeGlyphUsed(GID: Word);

procedure RegisterToUnicodeReverseMapping(SubstCodepoint: Cardinal; const SourceCodepoints: array of Cardinal);

procedure ClearToUnicodeReverseMappings;

function ToUnicodeReverseMappingCount: Integer;

function AssignSyntheticCodepointForGID(GID: Word; out SyntheticCP: Word): Boolean;

function GetSyntheticCodepointForGID(GID: Word): Word;

procedure MarkSyntheticCpRTL(Cp: Word);

function IsRTLSyntheticCp(Cp: Word): Boolean;

function IsRTLSyntheticGID(GID: Word): Boolean;

Covered APIs

API	Usage notes
`EnableShapingFeatureForSubset`	Marks GSUB features whose output glyphs must be retained in the embedded subset
`MarkUnicodeGlyphUsed`	Adds a returned substitute GID to the embedded font subset closure
`RegisterToUnicodeReverseMapping`	Registers a substitute codepoint to source-codepoint mapping for extraction and accessibility
`ClearToUnicodeReverseMappings`	Clears all caller-registered reverse mappings for the current document
`ToUnicodeReverseMappingCount`	Returns the number of registered reverse mappings
`AssignSyntheticCodepointForGID`	Allocates a private-use synthetic codepoint that renders a glyph ID through CIDToGIDMap
`GetSyntheticCodepointForGID`	Returns the synthetic codepoint already assigned to a glyph ID
`MarkSyntheticCpRTL`	Marks a synthetic codepoint as right-to-left so emit ordering remains correct
`IsRTLSyntheticCp`	Reports whether a synthetic codepoint was marked for right-to-left emission
`IsRTLSyntheticGID`	Reports whether a glyph ID resolves to a synthetic codepoint marked for right-to-left emission

Usage notes

ใช้ APIs เหล่านี้เมื่อ shaping workflow emit glyph IDs ที่เข้าถึงไม่ได้ผ่าน Unicode cmap entry ปกติ Synthetic codepoints route การ render ผ่าน CIDToGIDMap ส่วน reverse mappings กู้ source codepoints เดิมสำหรับ text extraction