Proposal talk:Rendering locks in Mapnik

The convention on large-scale (low zoom) waterway maps is to mark a lock with a single chevron, and a flight of locks with a pair of chevrons similar to the single lock representation on small-scale (high zoom) maps. I think this scheme should also be adopted for the Mapnik rendering. That way, a consistency of symbol is maintained on all the zoom levels that locks will be displayed. Malcolmh

INT 1

Rendering of locks should IMO follow INT 1 standard, even in Mapnik and Osmarender. See User:Skippern/INT-1 for more information about the INT 1 standard. There are several symbols for lock, depending on zoom level and type of lock. --Skippern 08:35, 24 September 2010 (BST)

I draw waterway maps for a living (inter alia) and can say that the INT-1 standard is ignored by pretty much every canal map I've ever seen in the UK, and several I've seen abroad. At large scales there simply isn't the room to show each individual gate. Rather, as Malcolmh says above, a single chevron represents the whole lock (gates and chamber) at large scales. At small scales individual gates may be shown (though they often aren't). A flight will sometimes be shown by one chevron per lock, but also sometimes as a pair of chevrons with the outer edges 'joined'.

The INT-1 standard is for hydrographic charts. Not all maps are hydrographic charts. --Richard 11:17, 11 November 2010 (UTC)

This page is flawed

"Proposed features" are for database tag suggestions. This is a cartographic issue and should be left to the cartographers. Having this page here makes about as much sense as "Proposed features/Potlatch should have a multiple selection feature" would. You are welcome to commit patches to Mapnik, osm2pgsql and the standard stylesheet which would achieve your desired aim; alternatively, you can lodge a trac ticket. But this page is absolutely the wrong place to put it. --Richard 11:17, 11 November 2010 (UTC)