Sorted, de-duplicated vertex indices from raw per-segment index data.
Uses a typed-array sort + single-pass dedupe rather than a JS Set,
which V8 caps at 2^24 (16,777,216) entries; the next .add throws
RangeError: Set maximum size exceeded. A lines node referencing more
than 2^24 unique vertex indices therefore silently failed to load
(issue #1049). Numeric ascending; the returned view aliases a fresh
copy, so the caller's segmentData is not mutated.
Sorted, de-duplicated vertex indices from raw per-segment index data.
Uses a typed-array sort + single-pass dedupe rather than a JS
Set, which V8 caps at 2^24 (16,777,216) entries; the next.addthrowsRangeError: Set maximum size exceeded. A lines node referencing more than 2^24 unique vertex indices therefore silently failed to load (issue #1049). Numeric ascending; the returned view aliases a fresh copy, so the caller'ssegmentDatais not mutated.