New in version 1.15.
TextClusterstructure holds information about a single text cluster. A text cluster is a minimal mapping of some glyphs corresponding to some UTF-8 text.
For a cluster to be valid, both
num_glyphsshould be non-negative, and at least one should be non-zero. Note that clusters with zero glyphs are not as well supported as normal clusters. For example, PDF rendering applications typically ignore those clusters when PDF text is being selected.
Context.show_text_glyphs()for how clusters are used in advanced text operations.