wishlist: fetch(url, update, ... and projection)

[christophe-g]

Hi,
It would be very handy in some case to add the current projection as an additional argument while fetching geojson features (line 1376)
if (url != null) {
tile.request = fetch(typeof url == "function" ? url(tile) : url, update, proj);
}

This would allow, for instance, to implement one's own rendering rules while converting geoJson to SVG - by providing an override for the update function in fetch (for instance, you might have a Point SVG feature that you wish to render not as a circle, but as another form, based on some feature's attribute or other rules). But for this, you need access to the current projection while processing the geometry.

Thanks again for this very nice piece of software

Cheers,
Christophe