CFS objects: Composite Fonts versus Fallback Fonts

Ken Lunde lunde at
Fri Jan 8 20:26:15 CET 2010


Early in the discussions of the Composite Font Standard there was talk about distinguishing Composite Fonts from Fallback Fonts, mainly because they are used in somewhat similar ways, but differ in some ways, such as the degree of fidelity for some attributes. A couple of days ago I came up with what could be used as a way to characterize the difference in concrete terms.

A Composite Font is a treated as though it were a new font, separate from other fonts that are installed. There is a measure of uniqueness inherent in a Composite Font. Thus, a CFS object that is treated as a Composite Font requires a unique name.

A Fallback Font is treated as a method of extending one or more installed fonts, to reference parts of other fonts to broaden (and modify) its character coverage. Thus, a CFS object that is treated as a Fallback Font does not require a unique name, and would simply use the naming attributes of the first <cfs:ComponentFont> tag. If the font specified in the first <cfs:ComponentFont> tag is not available, the subsequent ones would be thus be used.


-- Ken

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