The CharGrp.txt file for the font assigns each glyph to a character group: uppercase, lowercase, figure, or other. The character group tells Visual TrueType which group of values to use from the control value table (‘cvt’) for the glyph.
Occasionally, you might want to use the ‘cvt’ values from a different group. For example, the font designer may have classified a dollar sign ($) as a figure. However, while hinting it, you decide that the glyph looks more like an uppercase “S.”
Changing the glyph’s character group won’t affect ‘cvt’ values already applied to the glyph. However for subsequent ‘cvt’ values you assign, Visual TrueType will use the new character group.
Tip Change the character group, if necessary, before assigning any ‘cvt’ values.
Sometimes typographers turn on the sample text at the top of the main window (on the Display menu, click Show Text String) and cycle through all the character groups to check glyph spacing. The first part of the sample text displays the current glyph between two glyphs typical for the current character group, followed by extra text (see “Setting Preferences”).
For instance, if the current glyph is A, the text string starts with HHAHOHOAOOAAA. If you change the character group to lowercase, the text string starts with nnAnonoAooAA, which shows how the A spaces with those characters.
You make this change with the Change Char Group command from the Edit menu. Each time you choose the command, Visual TrueType changes the character group displayed in the status bar. Just keep choosing the command until the status bar displays the character group you want for the glyph in the main window.
To change the character group of the current glyph
1. On the Edit menu, click Change Char Group, or press Ctrl + U.
2. If necessary, repeat until the status bar displays the correct character group.