" text: [<glyph name or index>=<glyph cluster index within input>@<horizontal displacement>,<vertical displacement>+<horizontal advance>,<vertical advance>|...]\n"
" json: [{\"g\": <glyph name or index>, \"ax\": <horizontal advance>, \"ay\": <vertical advance>, \"dx\": <horizontal displacement>, \"dy\": <vertical displacement>, \"cl\": <glyph cluster index within input>}, ...]\n"