WorldCanvas – R/place, but with a real world map as the canvas

Show HN: WebGL mipmap renderer for a zoomable R/place on a real world map

WorldCanvas – R/place, but with a real world map as the canvas is a business in show hn launch.

Profile

I built a pixel canvas where you place tiles at real lat/lon coordinates on a world map – a 1.6M × 1.6M pixel grid (2.6 trillion addressable pixels). The technical challenge was making it feel smooth from zoom level 0 (whole world) to zoom level 18 (individual pixels).What I tried and what worked:- Canvas2D → WebGL: At wide zoom, Canvas2D couldn't keep up redrawing millions of pixels. Switched to a WebGL renderer with mipmap-style tile pyramids – pre-rendered lower-res textures for each zoom level, only loading full-res tiles when you're close enough.- Viewport-scoped SSE: Instead of broadcasting all pixel updates to every client, the server only streams changes within your current viewport

Its activity falls under show hn launch; the profile below is assembled from public directory data.

Directory data places it at the Show HN launch stage.

Website: worldcanvas.art