A new map renderer for OSM? Rasters, vectors, language and internationalization

Brandon Liu

Playlists: 'sotm2021' videos starting here / audio

I explore the spectrum of web map rendering techniques between raster and vector, and outline new approaches towards making universal map applications with OSM.

OSM's mission is to create a free, global dataset of geodata for diverse applications. A mainstream OSM use case is **web cartography**: the graphical display of geographic features on the standardized browser platform. Cartographers want to make beautiful, labeled, multi-resolution maps; maps need to be loaded progressively for a smooth user experience.

The web map status quo centers around two distinct approaches. One approach, used by the OSM Carto project, is server-rendered raster map tiles displayed as images in the browser. Another approach is to use a WebGL framework that consumes tiles of vector features. In the first part of this talk, I will investigate the tradeoffs inherent in these approaches with regards to **multilingual text and internationalization**, as these pose limitations for localizing OSM applications to different languages and cultures.

The second part of this talk will introduce new techniques and libraries for rendering OSM data that are a compromise between the raster and vector map ecosystems. I'll demonstrate some of these ideas in protomaps.js, a new Canvas2D and Leaflet-based open source map rendering library.