Make road-casing stronger

[matthijsmelissen]

Some roads should have a bit stronger casing, especially on low zoom levels. The new building colours will make this worse. This can be done either by making the colours darker, or by making the casing wider. A stronger casing will make the map more attractive and easier to read.

[mboeringa]

Some roads should have a bit stronger casing, especially on low zoom levels. The new building colours will make this worse. This can be done either by making the colours darker, or by making the casing wider. A stronger casing will make the map more attractive and easier to read.

If widening the casing also widens the road, I am not sure if that is a good thing. If anything, Openstreetmap-Carto needs less wide roads, instead of wider, as the wide road lines are a cause of multiple issues here in the bug tracker concerning overlapping objects (e.g. the "turning circle" problem as an infamous example: #811, #929, #1081). Openstreetmap-Carto already uses some of the widest road lines in any website I have seen, and looking at all the remarks where people point out renderings they find more attractive (e.g. MapQuest, Google), these renderings almost universally use roads thinner than in Openstreetmap-Carto.

This also hits on another fundamental choice: in Carto, it seems an attempt was made to keep road name labels within the casing of roads by widening roads, probably a choice for legibility. However, most other renderings allow the labels to overflow the casing, and use thin white halos and light coloured casings to overcome the legibility issue. This is also related to the recent change of #1010, and the issue I posted (#1089), as #1010 would undoubtedly need to be reverted if ever the choice was made to give Carto road widths less than the font's height, as in most other renderings, as the coloured halos overflowing casings would look ugly.

In fact, this latter point is already a minor issue, as letters like "g" and "y" will already overflow the casing, see the image below:

Also, widening the casing may make the commit of #1010 more of a problem, as I think the road names overlapping the darker casings with the lighter colour of the fill, will start showing up and not look good. Therefore, widening the casings, may again need a revert of #1010 and a return to neutral white halos instead.

[matthijsmelissen]

If widening the casing also widens the road,

It doesn't, the casing width is substracted from the total width.

Apart from that, good points.