When a text is rendered using a font, and a glyph appears in the text that is not present in the specified font, a substitute font may be selected to render that glyph. For instance, if the Arial font is used to render Japanese hieroglyphs, Arial Unicode MS font may be used to actually render the text. C1PrintDocument can analyze this and add the actual fonts used (rather than those specified) to the DocumentFonts and/or EmbeddedFonts collections. To do that, the FontHandling must be set to FontHandling.BuildActualDocumentFonts or FontHandling.EmbedActualFonts. The downside to those settings is that it takes time, making the document generate slower. Hence it may be recommended that those settings are used only if the document contains characters that may be missing from the fonts that are specified (for example, text in Far Eastern languages using common Latin fonts).
When font substitution is analyzed, the following predefined set of fonts is searched for the best matching font containing the missing glyphs: