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  • Special Tables
  • 'acnt'
  • 'ankr'
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  • 'bdat'
  • 'bhed'
  • 'bloc'
  • 'bsln'
  • 'cmap'
  • 'cvar'
  • 'cvt '
  • 'EBSC'
  • 'fdsc'
  • 'feat'
  • 'fmtx'
  • 'fond'
  • 'fpgm'
  • 'fvar'
  • 'gasp'
  • 'gcid'
  • 'glyf'
  • 'gvar'
  • 'hdmx'
  • 'head'
  • 'hhea'
  • 'hmtx'
  • 'hvgl'
  • 'hvpm'
  • 'just'
  • 'kern'
  • 'kerx'
  • 'lcar'
  • 'loca'
  • 'ltag'
  • 'maxp'
  • 'meta'
  • 'mort'
  • 'morx'
  • 'name'
  • 'opbd'
  • 'OS/2'
  • 'post'
  • 'prep'
  • 'prop'
  • 'sbix'
  • 'trak'
  • 'vhea'
  • 'vmtx'
  • 'xref'
  • 'Zapf'
• Instruction Set Summary
• Glyph Mappings
• Converting Outlines
• Font Feature Registry

The 'hvpm' table

The 'hvpm' table allows for part remapping within HVF, or Hierarchical Variation Fonts. As the name implies, HVF glyphs comprise components called composites that in turn comprise other components. Leaf-level components are called shapes; shapes and composites are collectively referred to as parts.

The 'hvpm' table is used in conjunction with an 'hvgl' table to replace parts by other parts during rendering. Fonts within a .ttc collection can share the same 'hvgl' table but each have a different 'hvpm' table (or none).

All quantities are little-endian with natural alignment.

Table header

The table header contains version information, the offset to the index of parts by part number, the total number of parts, and the number of visible parts. Visible parts are always first by part number.

'hvpm' Table Header

Field	Type	Comment
Version	UInt16	Currently 1
Flags	UInt16	Currently all zero
Map subtable offset	UInt32	From beginning of hvpm table

Mapping subtable

Subtable header

Field	Type	Comment
Count	UInt32	Number of ranges

The ranges follow immediately in the following format:

Field	Type	Comment
Start	UInt32	First part ID of range to map
End	UInt32	Last part ID of range to map
Destination	UInt32	First part ID to map to

Any part ID falling within a range will be mapped to id-Start+Destination. Any part ID that that does not fall within a range in the map is used unmodified. The ranges must be in ascending order by start and must not overlap.

Any substitute part S mapped from an original part O must be able to use the exact same rendering parameters as O. O and S must be of the same type (shape or composite), and have the same number of axes with the same semantic functions, in the same order. If both S and O are composites, they must have the same number of subparts, and all the above constraints apply recursively down the structure trees of O and S (as described in the 'hvgl' documentation).

Platform-specific Information

The 'hvpm' table is supported on macOS 15.6 and iOS 18.6 onward.

Dependencies

The 'hvpm' table works in conjunction with the 'hvgl' table.