Blogs on VonCannon Technology

Creating a USGS Topo Mosaic Map

Mon, 13 May 2024 09:44:50 -0400

The USGS topo maps are awesome … especially when using them for the outdoors or doing historical research.

The maps contain a great deal of information on public lands, national parks, nature preserves and most other United States public lands

The highlighted features include: trails, amenities, ranger stations, boundaries, elevation data, bathymetry, roads, contour lines, and hill shading, etc.

Even better the USGS has topo maps going all the way back to the year 1882. 🤩

Introducing Topo Lock Maps

Wed, 01 Mar 2023 13:06:52 -0400

I have decided to build my own outdoor mapping app.

Frustrated with most other mapping applications not providing a simple & private experience, why not just build my own?

Introducing Topo Lock Maps!

A simple, private, and secure outdoor mapping platform.

Features

⛺ Offline maps
🚶 Trails
⛰️ Terrain features / isolines / hill shading
🧰 Measuring tools
🦌 Hunt / game lands
🏠 Parcel data

Plus including extra awesome features:

A History of Map Glyphs, Fonts, and SDFs

Sat, 14 Jan 2023 00:00:00 -0400

A technical history and practical summary of how glyphs, fonts, and signed distance fields for vector maps were created back in the Mapbox days and how things look today after the MapLibre fork.

Mapbox introduced signed distance field (SDF) glyphs for efficient GPU text rendering in Mapbox GL; glyphs are packaged as small protobuf (.pbf) files indexed by Unicode ranges and served from a “glyphs” URL in the style.

The first blog post I see on this topic from Mapbox was on Jun 16, 2014 by Konstantin Käfer (PDF).