hdmx: Horizontal Device Metrics
The horizontal device metrics table is used for caching advance widths.
Requirements
- An 'hdmx' table is particularly important if advance widths do not scale linearly. If bit 4 of the flags field in the 'head' table is set, an 'hdmx' table should be present in the font.
- If the font includes an 'LTSH' table, the 'hdmx' values are not needed above the linearity threshold specified in the 'LTSH'.
Recommendations
- None additional to TTF spec.