If using Pango (Linux), set the shaping engine to x256-sinhala:
PangoContext *context = pango_font_map_create_context (pango_cairo_font_map_get_default ());
PangoAttrList *attrs = pango_attr_list_new();
pango_attr_list_insert(attrs, pango_attr_family_new("Noto Sans Sinhala x256"));
pango_attr_list_insert(attrs, pango_attr_register_sinhala_x256(TRUE)); // Custom attribute
If using HarfBuzz directly, enable the feature sinh-x256: sinhala x256
hb_feature_t feature;
feature.tag = HB_TAG('s','i','n','x'); // sin-x256 feature
feature.value = 1;
feature.start = 0;
feature.end = (unsigned int)-1;
hb_buffer_add_feature(buffer, &feature);
Sinhala x256 is a conceptual encoding and typographic approach that extends Sinhala script handling for high-density text processing, multilingual computing, and creative typography. It combines technical ideas from character encoding, font design, and text-rendering optimization to support large-scale Sinhala text workflows, especially where legacy encodings, Unicode limitations, or specialized layout needs arise. Example 2 — Web fallback: