Widen the star catalogue, and separate what is drawn from what is known

The map held 8750 stars within 50 pc and rendered 371 systems. Both were lower than they needed to be, for different reasons. The star catalogue was capped by its own encoding as much as by the cutoff: one JSON object per star, eight key names repeated each time, 157 bytes a star. At the range HYG actually reaches that is 17 MB to download and parse before the first frame. So the numbers move into two binary column stores — positions in stars.bin, which the GPU is handed verbatim, and id/magnitude/colour/spectral index in stars-meta.bin — and the JSON keeps only the strings, with 2600 distinct spectral classifications collapsed to a dictionary. The layout is defined once, in star-catalog.ts, and the ETL and the app both use it, so the writer and the reader cannot drift. The cutoff then goes to 250 pc: 68388 stars, 7.8x as many for 1.7x the bytes. That is where HYG's measurements stop rather than a round number — 98.6% of its rows are Hipparcos, whose parallaxes are good to about a milliarcsecond, so beyond 250 pc it would be plotting noise. Drawing all of them is a separate question from knowing them, and it is answered separately. The field draws a budget: every star inside 25 pc, because the nearest are faint red dwarfs and Proxima Centauri is magnitude 11, then the brightest of everything beyond. Search, navigation and the planet cross-reference still see the whole catalogue. A real GPU would draw all 68388 without noticing; the budget is for the machines that would not, and it is one constant. Systems were limited by something else entirely. The archive data already shipped named 4735 host stars and only 388 resolved, because the rest lay outside a 50 pc catalogue — and the cross-reference kept only its own result, so redoing it meant re-downloading an archive that is not reachable from here. Host coordinates are now stored with each planet, and the match is re-resolved at build time against whatever catalogue the run produced. Even name matching alone, which needs no coordinates and so works on the records already shipped, rescues 335 planets across 238 systems: 371 renderable systems become 609. Two selection rules were tuned for a 50 pc bubble and no longer fit. Tethers followed the Sun's nearest neighbours, which are a speck at this range, and now follow the brightest; labels were ranked by proximity, which named whatever sat nearest the middle of the screen, and are now ranked by brightness — so the view names Canopus, Achernar and Spica rather than a clump of catalogue designations. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01WaySiNst4HhDXBHnMy8p5G
2026-08-05 08:35:41 +00:00
parent 029162ff52
commit 29fd92d118
20 changed files with 692 additions and 49 deletions
@@ -312,3 +312,9 @@ Real photography where it exists, and a surface reasoned from measurements where
 - Frame against the reference grid's outer ring, which is always wider than the outermost orbit, and leave an explicit margin around it.
 - Raise the framing ceiling far enough to hold the solar system out to Pluto in a portrait window; only companions hundreds of AU out reach it now.
 - Floor the star's halo against the framed radius, so a star sized against its innermost orbit still reads at the distance that frames its outermost one.
+
+### ✓ Step 11: Widen the star catalogue, and separate what is drawn from what is known
+- Repack the catalogue as two binary column stores plus a string-only JSON index (`star-catalog.ts`, shared by the ETL and the app), so 7.8x the stars costs 1.7x the bytes instead of 12x.
+- Raise the distance cutoff from 50 pc to 250 pc — where Hipparcos parallaxes stop being trustworthy — taking the catalogue from 8750 stars to 68388.
+- Give the star field a render budget: every star inside 25 pc plus the brightest of the rest. Search, navigation and the cross-reference still see the whole catalogue.
+- Store each exoplanet's host coordinates and re-resolve the cross-reference against the current catalogue at build time, so widening the star list rescues systems without re-downloading the archive. Renderable systems: 371 to 609.