Removes unused glyphs from the font.
public bool RemoveUnusedGlyphs()
trueif unused glyphs were successfully removed from the font; otherwise,
This method might fail to remove unused glyphs in the following cases:
Font is not embedded. For such fonts the Embedded
- Font is used in a PdfTextBox or PdfComboBox and therefore all font glyphs should be preserved. A PDF reader or editor might be unable to change text in a control if some glyphs are missed in the font.
- Font is of an unsupported type. For now, only TrueType/OpenType (not CFF) fonts are supported.
This method is useful for decreasing size of produced PDF documents. The method creates a font subset with used glyphs only and embeds the subset in the current document.
A glyph is treated as used if the current document contains character drawn with the glyph.
This method does not remove unused glyphs from Type1 fonts.
Some PDF documents use a same font descriptor and font bytes in multiple fonts. In such cases, the call of this method for first font will also remove unused glyphs for all other fonts.