Compute ymax and ymin of a font

compute-font-ymax-ymin.py

#!/usr/bin/env python

import sys
import fontforge

if __name__ == '__main__':
    if len(sys.argv) != 2 and len(sys.argv) != 4:
        print('usage: {} <font> [<code-point-start> <code-point-end>]'.format(sys.argv[0]))
        sys.exit(1)

    font = fontforge.open(sys.argv[1])
    selection = font.selection

    if len(sys.argv) == 2:
        selection.all()
    else:
        start, end = int(sys.argv[2], 0), int(sys.argv[3], 0)
        selection.select(('ranges', 'unicode'), start, end)

    highest = max(selection.byGlyphs, key=lambda g: g.boundingBox()[3])
    lowest = min(selection.byGlyphs, key=lambda g: g.boundingBox()[1])

    print('ymax = {} (U+{:04X})'.format(highest.boundingBox()[3], highest.unicode))
    print('ymin = {} (U+{:04X})'.format(lowest.boundingBox()[1], lowest.unicode))