2009/12/15 John Smith <[email protected]>: > 2009/12/15 Steve Bennett <[email protected]>: >> IMHO, tagging "layer=1 bridge=yes" for a road going over water is an >> example of a hack, and "tagging for the renderer". The information >> "bridge=1" is more than enough to render with, so "layer=1" can *only* >> be interpreted as giving a renderer a crutch. > > Without layer information you'd be guessing if the road goes over the > water or the water goes over the road, or the water and road are at > the same level. > > You could come up with sane defaults, but that's making assumptions > rather than tagging explicitly so you know beyond a reasonable doubt. >
If you have a bridge or a tunnel you don't need a layer tag a bridge infers it "goes over" a tunnel that it "goes over" If there is neither a tunnel, or a bridge and no layer either then it must be a ford. If you mark bridge=yes, layer=1 you are repeating your self. which is where problems start, see database normalisation. Peter. _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
