Sets the HarfBuzz.codepoint_t that replaces variation-selector characters not resolved
in the font during shaping.
The not-found-variation-selector glyph defaults to #HB_CODEPOINT_INVALID,
in which case an unresolved variation-selector will be removed from the glyph
string during shaping. This API allows for changing that and retaining a glyph,
such that the situation can be detected by the client and handled accordingly
(e.g. by using a different font).
Sets the HarfBuzz.codepoint_t that replaces variation-selector characters not resolved in the font during shaping.
The not-found-variation-selector glyph defaults to #HB_CODEPOINT_INVALID, in which case an unresolved variation-selector will be removed from the glyph string during shaping. This API allows for changing that and retaining a glyph, such that the situation can be detected by the client and handled accordingly (e.g. by using a different font).