User Guide

Glyph Window
233
A more “graphical” font parameter is the font height. The font height
(measured in font units) is the measurement of the font that is used to
align strings in text. It is important not to confuse UPM and font height.
UPM is just a scaling base, and, for example, all Type 1 fonts have the same
UPM of 1000. Font height depends on the font design and may be different:
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The font height can be defined as the distance from the bottom of a letter
that is partially located below the baseline, like the ‘p’ character, and the
topmost point of an uppercase character, like ‘H’, or a tall lowercase
character, like ‘b’. Sometimes a font contains special glyphs that can be
taller than ‘b’, like an integral sign, but usually these glyphs are not
counted when font height is measured.
Reference Points
By default all coordinates are measured relative to the zero point of the
glyph. This is located at intersection of the baseline and the left sidebearing
line:
Zero poin t
Reference point
As an alternative, distances may be measured relative to the reference
point, which may be positioned by the Edit tool to any point in the glyph
space. Often a reference point is very useful when you are working on a
symmetrical shape.
By default the reference point is located on the position of the zero point.