User Guide

The next screen is the How many and how much dialog,
and it is just like the Easy mode screen described earlier.
The third screen is called Technique, and it looks like this:
The technique screen allows you to choose different kerning
techniques.
Direction to kern is a way of having Fontographer create
only kerning pairs which are negative (tighten), only kerning
pairs which are positive (spread), or both (spread and
tighten, which is the normal option).
Pairs to kern first is useful when you are controlling the
total number of kerning pairs Fontographer is allowed to
make (as specified in the “How many and how much”
screen). If you have told Fontographer that it can only
make 500 kerning pairs, for example, and Fontographer can
find 2,500 pairs which need kerning, Fontographer then
needs a way to decide which 500 pairs to include.
However, if you choose “Doesn’t matter,” Fontographer
will simply choose the first 500 it finds.
Most common pairs first will cause Fontographer to give
precedence to an internal list of common pairs, and output
them first to make sure they are included. If you are really
concerned about telling Fontographer which kerning pairs
are important, choose the “Open file of pairs” option from
the first screen.
Largest pairs first will cause Fontographer to order the 2,
500 pairs it found from largest value to smallest, and output
the 500 largest values. This is a ‘surefire’ way to set the
letter combinations which need kerning the most
desperately; however, you will find that many or most of
these are often the goofy symbols characters, or
punctuation characters (unless, of course, you told
Fontographer not to consider those—which would have
been smart—in the first screen).
The final option, Most common then largest, is what you
Fontographer User's Manual
5: Metrics: Spacing and Kerning Page #32