Copilotfree, in-browser
Ask me anything about your lessons or your code.
“What is a port?” · “Why is my code erroring?”
Ask me anything about your lessons or your code.
“What is a port?” · “Why is my code erroring?”
Web maps are stitched together from small square tiles addressed by zoom, x, and y, all drawn in Web Mercator, so panning and zooming never reload the whole page.
Tiles, Slippy Maps, and Zoom Levels
Web maps are stitched together from small square tiles addressed by zoom, x, and y, all drawn in Web Mercator, so panning and zooming never reload the whole page.
An Interactive Map with Leaflet
Leaflet turns a div and a few lines of JavaScript into a pannable, zoomable map with a basemap, markers, and clickable GeoJSON shapes.
Modern Vector Tiles with MapLibre GL
Vector tiles send a map's raw shapes instead of finished pictures, so a browser's own graphics processor draws and restyles the map instead of waiting on new images.
Sharing Data: WMS, WFS, and OGC APIs
A server can hand a web map either a picture of the data or the data itself, and the standard chosen decides which one arrives.
Choropleths, Popups, and Interaction
A web map earns its keep when color and click both carry meaning: shading polygons by a real rate and letting a viewer tap one for the number behind it.