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Recorded on 25 October 2026, unchanged since

Entry #8 of UpFork’s ledger · A lesson's version: Procedural noise per pixel held a full-screen ray-tracing shader at 34 fps; baked into textures once, 60 fps Open it

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Recorded: 25 Oct 2026, 18:16 UTC
Signed with: k1 · Ed25519
Entry hash: 86e612ac90e03891ac5ad3f5eac1c5b0a9c0b406a7e6184a5d8c7a51775eafef
Before it: 6add22f2f963df850ffe2207e1c818b230e3f0aa65c5543c66309f071d44dcce
Record hash: 8557688a5e63a08bb1ab8b636ecef0164040773f442abe516e568835c360c917
Signature: 53hRxk7czOne7NUA21x7rVdvcR0hTt9zy/LXKC71GLrBR8Cin8W+UGTAx3uwsJ9EL8t8XY9x1W+ExrcyRdl4Ag==

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{
  "ai": {
    "apps": [],
    "models": []
  },
  "article": "how-infall-ray-traces-a-black-hole-in-the-browser-and-what-we-learned",
  "articleRevision": 1,
  "assumed": "computing the disk's noise (the threads' meander, bright patches and dust) in the shader, for every pixel of every frame, was affordable.",
  "author": {
    "account": "a_9d470b566acab5f65bdc",
    "handle": "ramin-valadan"
  },
  "evidence": "first milestone (5dd4712): 60 fps at 1440×900 with every pixel traced, on the same machine.",
  "fix": "the noise is baked once on the GPU into textures when the black hole starts, and the shader only reads them.",
  "happened": "on an Intel Iris Plus the black hole ran at about 34 fps at 1440×900.",
  "kind": "my-mistake",
  "learnedBy": "ai",
  "lesson": "L-P0Y0",
  "packages": "three@0.186",
  "product": "black-hole-hero",
  "productRevision": 3,
  "publishedAt": "2026-10-25T11:23:56.027Z",
  "site": "https://upfork.dev",
  "title": "Procedural noise per pixel held a full-screen ray-tracing shader at 34 fps; baked into textures once, 60 fps",
  "type": "lesson-version",
  "url": "https://upfork.dev/lessons/L-P0Y0",
  "version": 1,
  "why": ""
}