[OSM-dev] OpenStreetMap Cartographic: A client-side rendered OpenStreetMap Carto

[Paul Norman]

I've been busy with

On 2020-05-24 10:26 p.m., Joseph Eisenberg wrote:
> Thank you for making this, it looks like a lot of work!
>
> These client-side vector tiles at z8? 
> (https://pnorman.dev.openstreetmap.org/cartographic/mapbox-gl.html)
>
> My laptop (2015 Macbook Pro, 16 GB RAM, 2.2 GHz Intel Core i7) appears 
> to use some effort to show areas with a large amount of data,
> For example if I view England + Wales on z8 and then move over to the 
> Netherlands and then to Germany, at z7 and z8,
> CPU usage goes up to >100% for a time, and there is a 
> noticeable delay. Perhaps part of this is a delay in serving the tiles?

I turned on Content-Encoding based compression which cuts the bytes 
transferred in half. This helps significantly.

In general vector tiles have more large tiles, even if the average tile 
size is the same. The largest z8 tile in the area is 1MB transfer size 
while an average weighted by requests on the tile.osm.org level 2 cache 
is 189k uncompressed. For comparison, four z9 raster tiles from 
tile.osm.org are about 200kb, a fifth of the bytes transferred. Retina 
tiles would decrease the size different.