User Guide

Hinting
553
Stems Rounding
Control over stem widths rounding is necessary for two reasons:
1. To control a font’s contrast. If your font is low contrast, like Courier or
Arial, you may want to set the jump PPMs for vertical and horizontal
stems equal. This way, the font will never get high contrast, as when
vertical stems are 2 pixels wide and horizontal stems are only 1 pixel
wide.
2. To synchronise the scaling of stems with close widths - like the stems
that control straight and round vertical stems in uppercase characters.
At large PPM sizes they should be different but they have to make the
1→2 and 2→3 width jumps together.
Bigger jump values are necessary when you are working on a black or extra
black font where 5-pixel width stems appear at low PPMs.
To change stem rounding:
1. In the list select the stem that you want to edit.
2. In the edit fields change the PPM sizes at which this stem makes its
various jumps from one pixel up to 6 pixels.
Press the
button to automatically optimize the stem rounding while
trying to keep optimal contrast. Use the
button to reset all stem PPMs
to linear values.