The string draw primitive only accepts a map with 256 indices into a bitmap,
so a single StrikeFont can at most be used to draw 256 different glyphs.
This is obviously not enough to display most content outside of ISO8859-1,
so a StrikeFontSet includes multiple StrikeFonts; each covering a 256-glyph
range of the Unicode character set (and also lets you use  different glyphs
depending on the leadingChar of the WideString, arguably useful for
preserving CJK)
Double dispatch then lets a WideString be drawn as consecutive calls to the
primitive with the pieces that are covered by a single StrikeFont entry in
the StrikeFontSet.

(At least, that's how my memory of how it should work is)



--
View this message in context: http://forum.world.st/StrikeFonstSet-vs-StrikeFont-tp4895960p4896167.html
Sent from the Squeak - Dev mailing list archive at Nabble.com.