raster-tiles SKILL.md skillA
raster-tiles from yuiseki/map-from-scratch is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add yuiseki/map-from-scratch/raster-tiles@git:20261026.79a684ePins git:20261026.79a684e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- yuiseki/map-from-scratch
- Path
.agents/skills/raster-tiles/SKILL.md- Versions recorded
- 1
- Latest version
- git:20261026.79a684e, committed Oct 26, 2026
- Size
- 32,683 bytes
- Repository stars
- 24
- License
- GPL-3.0
How 42 map engines draw raster tiles without seams, edge artefacts, flicker or runaway texture memory - tile placement and pixel snapping, kernel borders for hillshade and resampling, reprojection, ancestor fallback, browser decoding, GPU texture pools, tile size and DPR, and the payload codecs, no-data masks and COG range reads of baked rasters. Load it when a map-from-scratch renderer draws XYZ/PMTiles image tiles, a COG or GeoTIFF, terrain-RGB/DEM or hillshade, a georeferenced image…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Raster tiles: seams, borders, fallback, decoding and texture memory Drawing raster tiles looks like the easy part of a map: fetch z/x/y images and put each on a quad. The engines show where it goes wrong. Tiles placed at fractional pixels leave 1-2 px gaps [1][2]. A kernel (resampling, slope, hillshade) run per tile shows the tile grid [3][4]. Reprojecting at run time blurs the image and costs load time [5]. Missing tiles flash blank during zoom [6]. Decoding images on the main thread costs 20-30 ms per tile [7], and unbounded texture pools grow VRAM during fast zoom and pan [8]. Each engine paid for its fix in code, memory or extra draws. A purpose-built renderer can often move the fix to bake time, where a general engine cannot. This skill lists the decisions by sub-problem; per-engine history and numbers are in [references/engines.md](references/engines.md). The repository's own rules (bake at bake time, budgets, functional checks) are in `skills/map-from-scratch/SKILL.md` [9]. Neighbouring skills go deeper on DEM encoding and shading (`terrain-and-elevation`), parent/child level choice (`tile-lod-and-overzoom`), byte-range layouts (`data-range-requests`) and edge …
Read the whole file at its exact version.
How to install
mdr add yuiseki/map-from-scratch/raster-tiles@sha256:bc8d9bce0e7b80f0The line at the top of this page pins the label git:20261026.79a684e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_5e4phvnxfuyr55f2)
1 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Oct 26, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (32683 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
yuiseki/map-from-scratch · 24 stars · license GPL-3.0 · pushed 2026-11-06 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_5e4phvnxfuyr55f2 GET https://markdownregistry.com/api/v1/resolve?ref=yuiseki/map-from-scratch/raster-tiles GET https://markdownregistry.com/api/v1/blob/bc8d9bce0e7b80f046f536151b65c30d97ca264461b02564f474bbefd4564af9
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.