Boyd Shearer

• Senior Lecturer, UKy Department of Geography.
• Online Digital Mapping program 🔗
• outrageGIS mapping topographic trail maps. 🔗
• Contact.

UKy Digital Mapping

• Started in 2015
• and was called New Maps Plus.
• Open-source GIS and web mapping.
• Graduate Certificate and later MS degree

Examples

• Interactive choropleth maps. 🔗 Ok... 🔗
• Querying APIs for data. 🔗
• Jacob Saindon & Michael McCanless, 2023, NACIS winner 🔗
• Lis Fano, 2020, NACIS winner 🔗

Have long wanted to add 3D to the curriculum

with self-hosted terrain and vector tiles.

Existing providers

• Mapbox 🔗
• Maptiler Cloud 🔗
• Both offer vector tiles and 3D terrain tiles

Mapzen

• Terrain tiles, 2016. 🔗
• World-wide elevation data from 3DEP, SRTM, etc.
• Hosted as public domain tiles on AWS S3. 🔗

DEM data in the browser?

• 32-bit rasters won't work.
• RGBify it and tile it for web browsers. 🔗

MapLibre GL JS

• 2021 fork of Mapbox GL JS. 🔗
• Open-source WebGL JavaScript library.
• Renders 3D maps with vector, terrain, and raster tiles.

Kentucky

• Use raster tile services from
• kygisserver.ky.gov
• to get multiDirectional hillshade.

Awesome

• 3D maps rendered in browser.
• Completely free with no usage limits.
• But Ky has higher resolution elevation data
• and we need storage.

contig.us

• Linux server on Digital Ocean
• provisioned with open-source geospatial software.
• Students have SSH access to server.
• 60GB at $18/month.

Student goals

• Build a data pipeline
• to create raster and vector tiles
• hosted on the server.

Vector tiles

• Tile spec pioneered by Mapbox.
• Smooth, fast rendering of large datasets
• but need a vector tile server.
• That's where you get locked into a provider.

PMtiles

• "single-file archive format for pyramids of tiled data" 🔗
• provides self-hosted solution.
• Following example 40MB layer.

Pipeline

• PostGIS > GDAL > Tippecanoe > PMtiles
• See scripts/create-tiles.sh

KyFromAbove

• Create RGB elevation tiles from DEM
• See scripts/process-terrain.sh
• Pine Mountain comparison

Size

• 19 MB tile set per DEM tile.
• Better methods of creating tiles.
• 425 MB for a location like the Red River Gorge.

Does Ky have statewide RGB DEM tiles?

DSM

• Lidar first-return elevations.
• Create tile set for DSM.
• Problem with tall buildings.