Renderproblem: Some townlabel2e5 are visible, some are invisible

[SlowRider]

I saw the following happen: Some townlabel2e5 disappear sooner than others when zooming out.

Steps to reproduce:

• Navit SVN, gtk gui

• map based on osm data, medium size, home grown, area from colmar to wuerzburg

• search for stuttgart and center it on the map

• zoom in

• now zoom out step by step, until the label stuttgart disappears

• Now move the map along the A8, until Pforzheim appears. It also is a town of type 2e5, but its label is visible

• Continue to move the map along the A8 until Karlsruhe appears. There is no label, though Karlsruhe is a town of type 2e5 as well

• Move the map up to the north, until Speyer appears. Its label is visible. It's also a town of type 2e5.

No clue, but maybe this issue is related to #232.

[Mike]

I noticed that in my area (Kassel), the 2e5 label of Kassel even disappears earlier/appears later when zooming out/in than the 2e4 labels of smaller towns in that area...

Changing the order value of 2e5 labels in navit.xml doesn't seem to do anything for Kassel, either. Weird...

[KaZeR]

I've made the test explained above, and it now reacts as expected : if Stuttgart is visible, Pforzheim and Karlsruhe are visible too. If Stuttgart isn't visible, Pforzheim and Karlsruhe aren't neither. #232 was solved, this one looks solved too, to me.