> For the complete documentation index, see [llms.txt](https://hetcreep.gitbook.io/hetcreep-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hetcreep.gitbook.io/hetcreep-docs/sources.md).

# Sources

**The locator register for `SPRITE-DESIGN-DATUM.md`.** One row per external citation in the standard: where the claim lives, where the source lives, which version, and when someone last looked.

It exists because the standard's own instruction — *"VERIFY ANY VERSION-SENSITIVE CLAIM AGAINST ITS CITED SOURCE BEFORE RELYING ON IT"* (`LICENSE`) — was unexecutable. Every citation in the standard is a bare title. A reader could not click through, and both factual defects the first audit found survived precisely because of that.

## What this file deliberately does not contain

**No values.** Not a pixel dimension, not a tolerance, not a ceiling, not a percentage, not a default. The standard is the one home for every number, and a second copy of a number is the exact defect that document spends several pages warning about. The columns here are locators and dates.

**No verdicts.** A row records where a source is, not whether the standard read it correctly. A proven defect belongs in `ERRATA.md`; a held/moved/unreachable verdict belongs in the caretaker's re-validation record. Two rows below carry locators for claims an audit has questioned — the evidence is filed there, not here.

## How to re-run this

Fetch every `url` in order. Confirm the cited content is still on the page, then set `accessed` to the date you looked. A source that has moved gets its `url` corrected in place. A source that has died gets marked `UNREACHABLE` **with what was tried** — never deleted, and never replaced by a guessed URL. A row saying "could not reach, tried X and Y" is worth more than a plausible link that 404s for the next reader. `id` is stable and is never renumbered.

**Line numbers drift.** The `line` column was taken against the working tree at commit `3ad1e55` with uncommitted edits present on 2026-08-11 — an anchor-insertion pass had already shifted every line number in the second half of the file by roughly a hundred. Re-check the column whenever the standard's line count changes.

## Class

The standard's third standing rule: every citation states whether it is a **specification**, a **vendor document**, a **tool default**, or a **recommendation**. They do not weigh the same. The standard itself tags only seven of its citations inline, all of them `VENDOR_DOC` or `RECOMMENDATION`; `SPECIFICATION` and `TOOL_DEFAULT` appear zero times as a citation tag, though `TOOL_DEFAULT` names a register heading. Every class assignment below not carried by an inline tag in the standard was made here, by the caretaker, and is open to the owner's correction.

**One value outside the four.** The corpus rows (S-024, S-025) are classed `EXTERNAL-MEASURED` — the standard's own fourth evidence class. A corpus is material a measurement was taken from, not a document making a claim, and forcing it into one of the four would be the mis-attribution this register exists to prevent. This is a fifth enum value and a checker built to the four-value schema will reject it. That rejection is the intended signal, not an oversight.

## Re-validation intervals, by class of source

Chosen by how fast each class actually moves, not per row:

| class of source                                                        | interval | why                                                                                |
| ---------------------------------------------------------------------- | -------- | ---------------------------------------------------------------------------------- |
| Store and console policy (Google Play, App Store, Android)             | `90d`    | Fastest-moving class here. Accepted sizes and serving rules change without notice. |
| Engine documentation (Unity, Godot, Unreal)                            | `180d`   | Moves per release. Unity docs are per-version; Godot's `/en/stable/` is a pointer. |
| Rolling specifications (Vulkan `latest`, Metal MSL)                    | `1y`     | Versioned, but the URL tracks the newest revision rather than a frozen one.        |
| Tool defaults and atlas packers                                        | `1y`     | Move quietly at point releases; a changed default is never announced loudly.       |
| Corpora (rolling repositories)                                         | `1y`     | Content grows; licence structure and credit files are what matter and rarely move. |
| Purchasable standards on an edition cycle (ASME, ISO)                  | `5y`     | Edition cycles are long and publicly announced.                                    |
| Frozen specifications (OpenGL 1.0, WebGL1/GLES2, D3D9/D3D10, RFC 9111) | `never`  | Published and closed. They do not move; only their hosting does.                   |

`UNREACHABLE` is a state, not a schedule — such a row keeps its class's interval.

***

## Standards named in prose

| id    | cited as   | line | class         | url                                                                                        | version                | accessed   | revalidate |
| ----- | ---------- | ---- | ------------- | ------------------------------------------------------------------------------------------ | ---------------------- | ---------- | ---------- |
| S-001 | ASME Y14.5 | 53   | SPECIFICATION | <https://www.asme.org/codes-standards/find-codes-standards/y14-5-dimensioning-tolerancing> | 2018 (reaffirmed 2024) | 2026-08-11 | 5y         |
| S-002 | ISO 1101   | 53   | SPECIFICATION | UNREACHABLE — 403 on `iso.org/standard/66777.html` and on `iso.org/obp/ui`                 | unverified             | 2026-08-11 | 5y         |

S-001's catalogue page is public; the standard's text is sold, not published. S-002 could not be reached at all: ISO's catalogue and its Online Browsing Platform both returned 403. The edition is therefore recorded as unverified rather than guessed.

## Graphics API specifications

| id    | cited as                                                 | line | class         | url                                                                                                                        | version                 | accessed   | revalidate |
| ----- | -------------------------------------------------------- | ---- | ------------- | -------------------------------------------------------------------------------------------------------------------------- | ----------------------- | ---------- | ---------- |
| S-003 | "the only one WebGL/WebGPU exposes" (UV 0–1)             | 169  | SPECIFICATION | UNREACHABLE — 403 on `registry.khronos.org/webgl/specs/latest/1.0/`                                                        | WebGL 1.0               | 2026-08-11 | never      |
| S-004 | `VkSamplerCreateInfo::unnormalizedCoordinates = VK_TRUE` | 170  | SPECIFICATION | <https://docs.vulkan.org/spec/latest/chapters/samplers.html>                                                               | spec `latest` (rolling) | 2026-08-11 | 1y         |
| S-005 | `constexpr sampler s(coord::pixel, …)`                   | 171  | SPECIFICATION | <https://developer.apple.com/metal/Metal-Shading-Language-Specification.pdf>                                               | unversioned at the URL  | 2026-08-11 | 1y         |
| S-009 | "On WebGL1 specifically" — NPOT sampling restrictions    | 211  | SPECIFICATION | UNREACHABLE — 403 on `registry.khronos.org/webgl/specs/latest/1.0/`                                                        | WebGL 1.0 / GLES 2.0    | 2026-08-11 | never      |
| S-011 | "could not reach a Khronos *specification*" (ASTC)       | 236  | SPECIFICATION | UNREACHABLE — 403 across `registry.khronos.org`                                                                            | —                       | 2026-08-11 | 2y         |
| S-018 | OpenGL 1.0 (1992)                                        | 364  | SPECIFICATION | UNREACHABLE — 403 on `registry.khronos.org/OpenGL/specs/gl/glspec10.pdf` and on `registry.khronos.org/OpenGL/index_gl.php` | 1.0 (1992)              | 2026-08-11 | never      |
| S-043 | HTTP standards define the `max-age` **mechanism**        | 689  | SPECIFICATION | <https://www.rfc-editor.org/rfc/rfc9111.html>                                                                              | RFC 9111 (June 2022)    | 2026-08-11 | never      |

**`registry.khronos.org` blocks automated fetches.** Four distinct URLs on that host returned 403, including the one the standard's own honest-weakness note at line 236 says the sweep could not reach. The standard was right about the reach; the block is at the host, not the document. S-004 is reachable only because Khronos also publishes the Vulkan specification on `docs.vulkan.org`, which does not block. No equivalent unblocked mirror was found for WebGL 1.0, GLES 2.0, or OpenGL 1.0.

S-005 resolves and serves a PDF, but the file exceeds the fetch size limit, so its content and version string are unread. The locator is confirmed live; the citation is not confirmed present.

## Engine and runtime vendor documentation

| id    | cited as                                                     | line | class          | url                                                                                                                       | version                  | accessed   | revalidate |
| ----- | ------------------------------------------------------------ | ---- | -------------- | ------------------------------------------------------------------------------------------------------------------------- | ------------------------ | ---------- | ---------- |
| S-006 | Unity 2D Pixel Perfect package 5.0, *Pixel Perfect Camera*   | 187  | VENDOR\_DOC    | <https://docs.unity3d.com/Packages/com.unity.2d.pixel-perfect@5.0/manual/index.html>                                      | package 5.0.3            | 2026-08-11 | 180d       |
| S-007 | Unity Manual, *Import a texture*                             | 199  | RECOMMENDATION | <https://docs.unity3d.com/Manual/ImportingTextures.html>                                                                  | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-008 | Unity Manual, *Import a texture*                             | 209  | VENDOR\_DOC    | <https://docs.unity3d.com/Manual/ImportingTextures.html>                                                                  | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-010 | "MDN tutorial prose"                                         | 215  | VENDOR\_DOC    | <https://developer.mozilla.org/en-US/docs/Web/API/WebGL\\_API/Tutorial/Using\\_textures\\_in\\_WebGL>                     | unversioned              | 2026-08-11 | 180d       |
| S-012 | BCn on **Direct3D 11 and earlier**                           | 233  | VENDOR\_DOC    | <https://learn.microsoft.com/en-us/windows/win32/direct3d10/d3d10-graphics-programming-guide-resources-block-compression> | page updated 2025-04-15  | 2026-08-11 | never      |
| S-013 | Godot 4 documentation, *Multiple resolutions*                | 281  | RECOMMENDATION | <https://docs.godotengine.org/en/stable/tutorials/rendering/multiple\\_resolutions.html>                                  | `/en/stable/` serves 4.7 | 2026-08-11 | 180d       |
| S-014 | Aseprite (`sourceSize` / `spriteSourceSize`)                 | 321  | VENDOR\_DOC    | <https://gist.github.com/dacap/db18e5747a4b6e208d3c>                                                                      | unversioned              | 2026-08-11 | 1y         |
| S-015 | libGDX (`offsetX` / `originalWidth`)                         | 322  | VENDOR\_DOC    | <https://github.com/libgdx/libgdx/blob/master/gdx/src/com/badlogic/gdx/graphics/g2d/TextureAtlas.java>                    | `master`                 | 2026-08-11 | 1y         |
| S-016 | Unity (`Sprite.pivot` in import metadata)                    | 322  | VENDOR\_DOC    | <https://docs.unity3d.com/ScriptReference/Sprite-pivot.html>                                                              | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-019 | `SpriteAlignment.BottomCenter` — Unity ScriptReference       | 381  | VENDOR\_DOC    | <https://docs.unity3d.com/ScriptReference/SpriteAlignment.BottomCenter.html>                                              | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-022 | `Sprite.pixelsPerUnit` — Unity ScriptReference               | 418  | VENDOR\_DOC    | <https://docs.unity3d.com/ScriptReference/Sprite-pixelsPerUnit.html>                                                      | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-023 | `SpriteBase3D.pixel_size` — Godot 4 documentation            | 420  | VENDOR\_DOC    | <https://docs.godotengine.org/en/stable/classes/class\\_spritebase3d.html>                                                | `/en/stable/` serves 4.7 | 2026-08-11 | 180d       |
| S-031 | Unity Manual, *Import a texture* (texture dimension ceiling) | 624  | VENDOR\_DOC    | <https://docs.unity3d.com/Manual/ImportingTextures.html>                                                                  | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-032 | Unreal Engine, *Texture Format Support and Settings*         | 625  | VENDOR\_DOC    | <https://dev.epicgames.com/documentation/en-us/unreal-engine/texture-format-support-and-settings-in-unreal-engine>        | UE 5.8 documentation     | 2026-08-11 | 180d       |
| S-033 | Unity Manual, *Sprite texture type reference*                | 626  | VENDOR\_DOC    | <https://docs.unity3d.com/Manual/texture-type-sprite.html>                                                                | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-034 | Unity 2D Pixel Perfect 5.0                                   | 627  | VENDOR\_DOC    | <https://docs.unity3d.com/Packages/com.unity.2d.pixel-perfect@5.0/manual/index.html>                                      | package 5.0.3            | 2026-08-11 | 180d       |
| S-035 | Unity, corroborated by Godot and Unreal                      | 638  | RECOMMENDATION | <https://docs.unity3d.com/Manual/ImportingTextures.html>                                                                  | Unity 6.5 (6000.5)       | 2026-08-11 | 180d       |
| S-036 | Godot 4, *Multiple resolutions*                              | 639  | RECOMMENDATION | <https://docs.godotengine.org/en/stable/tutorials/rendering/multiple\\_resolutions.html>                                  | `/en/stable/` serves 4.7 | 2026-08-11 | 180d       |

**Godot's `/en/stable/` is a moving pointer, not a version.** On the access date it serves **Godot 4.7**. A reader following these URLs a year from now will be reading a different engine release under the same URL; that is why the version column records what `stable` resolved to rather than repeating the word.

**Unity's versionless URLs redirect to the current release**, which on the access date is **Unity 6.5 (6000.5)**. Pinning a version into the path (`/6000.5/Documentation/Manual/...`) freezes the content but eventually 404s as old versions age out, so the versionless form is recorded and the resolved version noted beside it.

Two title mismatches, neither of them a defect in substance. S-033's page is titled *"Sprite (2D and UI) texture Import Settings window reference"*, not *"Sprite texture type reference"*. S-035's attribution names Godot and Unreal as corroborating the Unity recommendation but names no Godot or Unreal page; only the Unity locator can be supplied without guessing.

## Store and platform policy

| id    | cited as                                                              | line | class          | url                                                                                                      | version     | accessed   | revalidate |
| ----- | --------------------------------------------------------------------- | ---- | -------------- | -------------------------------------------------------------------------------------------------------- | ----------- | ---------- | ---------- |
| S-017 | "An Android App Bundle that targets texture compression formats…"     | 353  | VENDOR\_DOC    | <https://developer.android.com/guide/playcore/asset-delivery/texture-compression>                        | unversioned | 2026-08-11 | 90d        |
| S-026 | Google Play Console Help, *Add preview assets* (screenshot, per side) | 619  | VENDOR\_DOC    | <https://support.google.com/googleplay/android-developer/answer/9866151>                                 | unversioned | 2026-08-11 | 90d        |
| S-027 | Google Play Console Help (screenshot, aspect)                         | 620  | VENDOR\_DOC    | <https://support.google.com/googleplay/android-developer/answer/9866151>                                 | unversioned | 2026-08-11 | 90d        |
| S-028 | Google Play Console Help (listing icon)                               | 621  | VENDOR\_DOC    | <https://support.google.com/googleplay/android-developer/answer/9866151>                                 | unversioned | 2026-08-11 | 90d        |
| S-029 | Google Play Console Help (feature graphic)                            | 622  | VENDOR\_DOC    | <https://support.google.com/googleplay/android-developer/answer/9866151>                                 | unversioned | 2026-08-11 | 90d        |
| S-030 | Apple, App Store Connect Help (screenshot sizes)                      | 623  | VENDOR\_DOC    | <https://developer.apple.com/help/app-store-connect/reference/app-information/screenshot-specifications> | unversioned | 2026-08-11 | 90d        |
| S-037 | Google Play Console Help (listing aspect targets)                     | 640  | RECOMMENDATION | <https://support.google.com/googleplay/android-developer/answer/9866151>                                 | unversioned | 2026-08-11 | 90d        |

All four Google Play rows resolve to one page. Neither store versions or dates its help pages, so `accessed` is the only handle a reader has on when the policy was read — which is why this class carries the shortest interval in the register.

## Tool defaults and atlas packers

| id    | cited as             | line | class         | url                                                                                             | version                | accessed   | revalidate |
| ----- | -------------------- | ---- | ------------- | ----------------------------------------------------------------------------------------------- | ---------------------- | ---------- | ---------- |
| S-020 | cocos2d-x            | 391  | TOOL\_DEFAULT | <https://docs.cocos2d-x.org/api-ref/cplusplus/v4x/d3/d5c/classcocos2d\\_1\\_1\\_sprite.html>    | v4.x                   | 2026-08-11 | 1y         |
| S-021 | Tiled                | 395  | TOOL\_DEFAULT | <https://doc.mapeditor.org/en/stable/manual/objects/>                                           | `/en/stable/` → 1.12   | 2026-08-11 | 1y         |
| S-038 | Unity Sprite Atlas   | 648  | TOOL\_DEFAULT | <https://docs.unity3d.com/6000.3/Documentation/Manual/sprite/atlas/sprite-atlas-reference.html> | Unity 6.3 LTS (6000.3) | 2026-08-11 | 180d       |
| S-039 | libGDX TexturePacker | 649  | TOOL\_DEFAULT | <https://libgdx.com/wiki/tools/texture-packer>                                                  | unversioned (wiki)     | 2026-08-11 | 1y         |
| S-040 | TexturePacker        | 650  | TOOL\_DEFAULT | <https://www.codeandweb.com/texturepacker/documentation/texture-settings>                       | unversioned            | 2026-08-11 | 1y         |
| S-041 | Godot                | 651  | TOOL\_DEFAULT | UNREACHABLE — no such default located; see below                                                | —                      | 2026-08-11 | 180d       |

S-038 is the one row that had to be version-pinned: the versionless `docs.unity3d.com/Manual/sprite-atlas-reference.html` returns 404, and the page lives under a version-and-section path. Expect this locator to need repair sooner than its siblings.

**S-041 could not be located.** Godot's `ResourceImporterTextureAtlas` documents four import properties and none of them is a padding; the *Importing images* tutorial documents no atlas padding; a site-restricted search of `docs.godotengine.org` surfaced no page stating one. What the search did surface was community guidance, which is not a tool default and must not be promoted to one. The row is recorded as unreachable rather than filled with a plausible URL. It is a third citation without a findable source, alongside the two the audit already named.

S-040's page states the "at least" guidance the standard quotes but publishes no default value for it, which makes `TOOL_DEFAULT` the weaker of the two possible classes for that row; `RECOMMENDATION` is arguably the truer one. Owner's call — the register does not reclassify a citation on its own.

## Corpora

| id    | cited as                                        | line | class             | url                                                                                  | version               | accessed   | revalidate |
| ----- | ----------------------------------------------- | ---- | ----------------- | ------------------------------------------------------------------------------------ | --------------------- | ---------- | ---------- |
| S-024 | Universal LPC Spritesheet (Liberated Pixel Cup) | 572  | EXTERNAL-MEASURED | <https://github.com/LiberatedPixelCup/Universal-LPC-Spritesheet-Character-Generator> | unversioned (rolling) | 2026-08-11 | 1y         |
| S-025 | Battle for Wesnoth                              | 579  | EXTERNAL-MEASURED | <https://github.com/wesnoth/wesnoth>                                                 | unversioned (rolling) | 2026-08-11 | 1y         |

Both repositories exist, both ship the per-file credit files the standard names (`CREDITS.csv`, `copyrights.csv`), and both describe the per-file licence structure the standard describes. The standard already prints these two locators inline as bare `github.com/...` paths — they are the only two citations in the whole document that carry any locator at all.

## Locators for claims the standard makes without naming a source

These rows are **not** citations in the standard. Each supplies the locator for a claim the standard states with no attribution, or with an attribution an audit has questioned. They are recorded here so the owner has the right URL in hand when deciding what, if anything, to do about the frozen text.

| id    | cited as                                                                    | line | class         | url                                                                                                                 | version                 | accessed   | revalidate |
| ----- | --------------------------------------------------------------------------- | ---- | ------------- | ------------------------------------------------------------------------------------------------------------------- | ----------------------- | ---------- | ---------- |
| S-042 | Microsoft Learn, *Bilinear Texture Filtering*                               | 668  | VENDOR\_DOC   | <https://learn.microsoft.com/en-us/windows/win32/direct3d9/bilinear-texture-filtering>                              | page updated 2025-03-11 | 2026-08-11 | never      |
| S-044 | *(not attributed)* — Coordinate Systems (Direct3D 10)                       | 668  | VENDOR\_DOC   | <https://learn.microsoft.com/en-us/windows/win32/direct3d10/d3d10-graphics-programming-guide-resources-coordinates> | page updated 2025-03-11 | 2026-08-11 | never      |
| S-045 | *(not attributed)* — Vulkan sampling coordinate systems                     | 668  | SPECIFICATION | <https://docs.vulkan.org/spec/latest/chapters/textures.html>                                                        | spec `latest` (rolling) | 2026-08-11 | 1y         |
| S-046 | *(not attributed)* — "block-compression documentation from tooling vendors" | 237  | VENDOR\_DOC   | <https://github.com/ARM-software/astc-encoder/blob/main/Docs/FileFormat.md>                                         | `main`                  | 2026-08-11 | 1y         |

S-042 is live and the page is exactly what its title says, but the substance the standard attributes to it is not on it. S-044 and S-045 are where that substance actually lives.

S-046 supplies the vendor-level locator for the ASTC padding correction. The standard states at line 237 that the correction is "corroborated at **vendor level only** (block-compression documentation from tooling vendors)" and names no vendor — this is Arm's own encoder documentation, and it states the padding behaviour directly. The standard's honest weakness at line 236 stands unchanged: this is vendor documentation, not the Khronos specification, and it must keep being cited as such.


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