The DumpVMTX tool allows you to dump the data in a TrueType font's 'vmtx' (Vertical metrics) table into a text file, which you can then examine. The edited file can subsequently be used as input to the FuseVMTX tool (q.v.)
DumpVMTX provides a menu bar for application control. You can use it by dropping a font on it, or you can use the File menu to specify a font to open.
While the dump is proceeding, a dialog box will appear with a progress bar. You can press Command-. to cancel (hold down the Command key and press <period>.)
Documentation on the 'vmtx' table format can be found in Apple's on-line TrueType specification.
If you encounter problems with DumpVMTX, please contact the Apple Font Group.
The File menu has an Open item. Use this to select a font whose 'vmtx' table you wish to dump. You can also dump a 'vmtx' table by dropping a font file on your DumpVMTX application's icon. Note that the font must have a 'vmtx' table for you to open it. If you open a font file containing more than one font, a dialog box will be presented allow you to select a font from those in the file.
The Options menu allows you to control how DumpVMTX formats data in the final dump file. The options are:
Most TrueType fonts will give each glyph in the font a name through the font's 'post' table. Use this option to include these glyph names in the mapping data dump.
Names are provided by the Unicode consortium for characters within the standard. If this option is selected, DumpVMTX will include those names (as possible) within the data dump.
Ordinarily, the dump process is fast enough not to be a problem. For a large file, however, you may want to turn your attention to something else and have your Macintosh make a pleasant sound when it's finished.
Last updated: JHJ