Font Substitution Data

The first classification of data stored in the font table are an optional set of font metrics which are queried from the font and stored in the document such that future applications can utilize them when the desired font is not available. If a particular font face cannot be located on the current system, then this data is used to substitute a font that most appropriately matches its characteristics.

For example, consider the font substitution data stored for the Arial Black font:

<w:font w:name="Arial Black">
  <w:panose1 w:val="020B0A04020102020204" />
  <w:charset w:val="00" />
  <w:family w:val="swiss" />
  <w:pitch w:val="variable" />
  <w:sig w:usb0="00000287" w:usb1="00000000" w:usb2="00000000"
    w:usb3="00000000" w:csb0="0000009F" w:csb1="00000000" />
</w:font>

This data is linked to the font face with a name of Arial Black via the @name attribute, and stores the following information about the font (see the reference material on fonts for more details):

• The font's Panose-1 number

• The character set of the font

• The font's family

• The font's pitch

• The code pages and Unicode sub ranges supported by the font