User Guide

Hinting
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T y p e 1 Hi nt s
As you know from the “Glyph Window” chapter, there are two kinds of
Type 1 Hints – font level hints and character-level hints.
Font-level hints define important vertical positions in the font, the most
commonly used stem widths and some other important data that helps
control the hinting process.
Character-level hints are used to declare the position and width of the
most important character elements. The most common use for hints is to
declare the position and width of character stems. These hints are scaled
with the outline in the rendering stage, but due to their independence from
the outline, they help to maintain the same stem widths for all stems of a
certain width, independent of how it happens to fall on the discrete raster:
Unhinted character Hinted character
Notice that in the unhinted character the outline falls on the grid such that
two rows of pixels would be turned on for the right vertical stem. The hint
forces the right stem to become the same width as the left stem in the
hinted character.
In the following sections we will discuss font-level hints and the process
called hint programming that is required at times.