function TextObjectGlyphWidth(Index, GlyphIndex: Integer; FontSize: Single): Single;
TextObjectGlyphWidth queries the native text object at Index for the advance width of glyph GlyphIndex, scaled to FontSize in PDF user units
The result is 0 when the index is not a text object, the glyph index is out of range, or the native API is unavailable in the loaded DLL
TextObjectGlyphOutline for path geometry and TextObjectFontSize for the object-level sizeW := Pdf1.TextObjectGlyphWidth(ObjIdx, GlyphIdx, 12);