GPOS–1: Pair Adjustment Positioning

• First, a PairPos format 1 subtable that adjusts the spacing between pairs of individual letters. For example, when Ą and J stand next to each other, their shapes would overlap. From a typographic perspective, this would look rather terrible, so this subtable puts them further apart.
• Second, a PairPos format 2 subtable that adjusts the spacing betwen glyph classes. For example, when they appear on the left-hand side of a letter pair, this subtable categorizes the letters A Á Ą into one particular class, G Ģ into another, and V into yet another class. The same happens for the right-hand side: a á ą are put into one glyph class, f fi fl into another, and so on. Finally, the subtable contains a table how to change the spacing for each combination of classes. Compared to format 1, this encoding can be more compact.