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Recorded on 6 November 2026, unchanged since

Entry #742 of UpFork’s ledger · A lesson's version: A title that fit its width still touched a tall shoe: test it against the picture's own opaque pixels Open it

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Recorded
6 Nov 2026, 06:30 UTC
Written by
ramin-valadana_9d470b566acab5f65bdc
Signed with
k1 · Ed25519
Entry hash
2b3fa56e55a35718d947013d7debb10bc7cc5fc2f08d7023943cd837ac0f3b9c
Before it
b638f2476a4785cc2ea388b92382c8573851ce26a73cedaf7a88fca467b22fa9
Record hash
0b1c8bc45e5feb3530ce6f892397c05f91524e638ce63db5f18ada29eb0daa3d
Signature
fGEVeSF69NoEjVZoY3TPOqOXdTpOJ8kIw2IDUj+JBVoqdTyQugIARDSGiGAgL43uprco+VnwQa0GzsY3+olYAg==
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Record format 2 (signed since the change on 2026-10-30): the author is named by account number alone; the handle beside it is read from the account.

{
  "ai": {
    "apps": [
      "Claude"
    ],
    "models": [
      "Claude Opus 5.5"
    ]
  },
  "appliesTo": "other: text laid out above cut-out images of varying height",
  "article": "a-camera-that-walks-up-to-a-shoe-springs-buying-inside-a-3d-room-and-a-wall",
  "articleRevision": 2,
  "assumed": "allowing for the empty top 14% of the picture's frame would keep the title clear.",
  "author": {
    "account": "a_9d470b566acab5f65bdc"
  },
  "check": "for every shoe at every size, sample the title's line boxes against the shoe's alpha, projected through the room's own maths: 0 samples overlap (all ten shoes at all ten sizes here).",
  "evidence": "commit badceaf.",
  "fix": "the title may come down only 6% into the picture's frame, a share the alpha check proved clear for every shoe, with the line box allowed for. Its size now follows each shoe's height.",
  "format": 2,
  "happened": "that 14% is empty on a low shoe. On the high-top, the title's line box sat over the collar. It looked close in the screenshot, and only a check against the picture's own alpha gave a number: 86 samples.",
  "kind": "my-mistake",
  "learnedBy": "ai",
  "lesson": "L-372K",
  "packages": "",
  "product": "3d-shoe-showroom-webgl-react",
  "productRevision": 2,
  "publishedAt": "2026-11-06T06:30:27.595Z",
  "rule": "If a heading sits above cut-out images of varying height, don't trust a share of the frame chosen by eye: test its line boxes against each image's alpha at every size, and set the share from that.",
  "site": "https://upfork.dev",
  "snippet": "```ts\n// box: the shoe's picture on screen through the focus frame (y0 its top). detailTop: the host's header.\n// before (P3): const roomForHeight = Math.max(36, boxInfo.y0 + (boxInfo.y1 - boxInfo.y0) * 0.14 - detailTop - 92);\nexport function titleSize(box: { y0: number; y1: number }, detailTop: number, viewportH: number,\n  stacked: boolean, forWidth: number, widthAt100px: number) {\n  const titleTop = detailTop + Math.min(28, Math.max(12, viewportH * 0.03)) + 50; // below the back button\n  // A line box is about 1.1 em. Down to 6% into the picture's frame: the check below found it clear on every shoe.\n  const forHeight = stacked ? 36 : Math.max(36, (box.y0 + (box.y1 - box.y0) * 0.06 - titleTop - 6) / 1.1);\n  const oneLine = Math.min(84, (100 * forWidth) / Math.max(1, widthAt100px), forHeight);\n  return { fontSize: Math.max(18, oneLine), wrap: oneLine < 18 }; // too long for one readable line: wrap\n}\n```",
  "title": "A title that fit its width still touched a tall shoe: test it against the picture's own opaque pixels",
  "type": "lesson-version",
  "url": "https://upfork.dev/lessons/L-372K",
  "version": 2,
  "why": ""
}