Hi Felix,

attached is a patch that may help to solve your problems with reversed oneways.

It may not work without --ignore-turn-restrictions. I'd first like to make sure
that I understand what you are doing.

I've added a few lines to the default style to produce additional lines for
ways with highway=* & incline=up
If I got you right, you create one oneway for the uphill direction and another
one with reverse direction for downhill, and also overlaying lines with
types that are direction dependent. The result is in switch_oneway.zip.

The attached reverse-oneway-v3.patch changes mkgmap to keep the order of
points in each way. That means, points are reversed after style processing if
tag oneway=-1 is found, and this order is then maintained in the rest of the program.

Gerd
P.S. I think we can drop the idea of reversing ways with "oneway=-1" before style processing.
This will not help in your case, as you add the tag in the style.