This extension helps with creating Italics on the font and glyph level, while drawing a "bowtie" in the Current Glyph Window to show the relationship of a font’s vertical and slanted sidebearings.
First, Set the italic angle you want in the Italic Bowtie dialog (usually a negative number).
Then determine your Cross Height. In your Current Glyph Window, you will see this value represented as the vertical height where the bowtie shape crosses itself. Press “Mid UC” to set the Cross Height to half of the cap height, which will offset the italic until your capitals are centered between vertical sidebearings. Alternatively, press “Mid LC” to set the Cross Height to half of the x-height, which will offset the italic until your lowercase is centered between vertical sidebearings.
Once the Cross Height is set, the extension will determine the appropriate Italic Slant Offset for this arrangement.
Once you have Italic Angle and Italic Slant Offset values that you are happy with, you can set them in the Current Font or All Open Fonts by pressing “Set Font Italic Values”.
The italicize button will skew and offset your Current Glyph, Selected Glyphs, or All Glyphs in either the Current Font or All Open Fonts.
If you select a reference layer, it will also draw a skewed and rotated glyph in a separate layer, for you to use as a reference as you fix the curves. This is based on a script by Cyrus Highsmith.