Name the columns stars-meta.bin gained in the README

The README listed the four columns stars-meta.bin had before a81dd49 added the photometry byte
(magnitude band, colour system, whether the distance is Gaia's) and the distance's relative
error.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-09-24 23:48:28 +02:00
co-authored by Claude Opus 5.5
parent b46c840369
commit 81a4ecfcde
+2 -1
View File
@@ -208,7 +208,8 @@ The star catalogue ships as two binary column stores plus a small JSON file, not
objects. At 68 388 stars the old encoding — one JSON object per star, its eight key names objects. At 68 388 stars the old encoding — one JSON object per star, its eight key names
repeated each time — would have been about 17 MB to download and parse before the first frame. repeated each time — would have been about 17 MB to download and parse before the first frame.
Splitting it puts the numbers in `stars.bin` (positions, handed to the GPU verbatim) and Splitting it puts the numbers in `stars.bin` (positions, handed to the GPU verbatim) and
`stars-meta.bin` (id, magnitude, colour index, spectral-type index), and leaves `stars-index.json` `stars-meta.bin` (id, magnitude, colour index, spectral-type index, the band and colour system
those were measured in, and the distance's relative error), and leaves `stars-index.json`
holding only the strings, with the ~2 600 distinct spectral classifications collapsed into a holding only the strings, with the ~2 600 distinct spectral classifications collapsed into a
dictionary. The result is 2.6 MB for 7.8× the stars. `star-catalog.ts` defines the layout once dictionary. The result is 2.6 MB for 7.8× the stars. `star-catalog.ts` defines the layout once
and both the ETL and the app use it, so the writer and the reader cannot drift apart. and both the ETL and the app use it, so the writer and the reader cannot drift apart.