User Guide

Hinting
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S t a n d a r d St e m s
There are two sets of standard stems in FontLab: Type 1 standard stems
and TrueType stems. Type 1 stems are used by the Type 1 font rasterizer
and have some limits. For example, it is possible to define only 12 stems for
each direction.
TrueType stems have no limits and also have some additional properties.
They may be named and their rounding may be specified for selected
PPMs.
In FontLab you can control the rounding of the standard stem widths. You
can set the PPM size at which any standard stem width is changed from 1
to 2 pixels, from 2 to 3 pixels, from 3 to 4 from 4 to 5 and from 5 to 6 pixels.
We call these critical PPM sizes “jump” PPMs because here the stem width
makes a jump from 1 to 2 pixels, from 2 to 3 pixels and so on up to 6 pixels
wide. By default, standard stems are scaled linearly and are rounded to the
closest integer value.
When you add a new Type 1 stem, it is added to both stem lists: Type 1
(editable with FontInfo) and TrueType.