User Guide

Hinting
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All untouched points usually interpolate (by the last glyph program
command) between the new positions of touched points.
Original outline Hinted outline Hinted outline
before interpolation after final interpolation
There are several special commands that are applied to the glyph outline at
specific PPMs. These commands are called delta instructions and are used
to slightly modify the position of outline points to improve the character’s
appearance.
We will not include here a complete description of all TrueType
instructions. If you are interested we recommend that you read “Technical
Specifications for TrueType Font Files” which is available from Microsoft.