freetypy.TT_OS2.typo_line_gap

TT_OS2.typo_line_gap

The typographic line gap for this font. Remember that this is not the same as TT_HoriHeader.line_gap, which Apple defines in a far different manner.

The suggested usage for typo_line_gap is that it be used in conjunction with TTHeader.units_per_em to compute a typographically correct default line spacing. Typical values average 7-10% of units per em. The goal is to free applications from Macintosh or Windows-specific metrics which are constrained by backward compatability requirements. These new metrics, when combined with the character design widths, will allow applications to lay out documents in a typographically correct and portable fashion.