This is a fix for the "first step on the stairs problem", see #144. I create a merge request because there are changes in the sensitive code part PedestrianOSM class, so maybe someone has the time to peer review it (even when all tests pass). I am not sure if there are better solutions, so I am also happy for suggestions. This also adds more computational resources, unfortunately, in the already current bottleneck: There are two checks (before and after) if someone is on the stairs.
Bugfix closes #144
The position of the first step of an agent onto the stairs is projected onto the first tread (wrt direction). The correction makes sure that the first step is a legal step according to the optimal stairs model.
See merge request !34 (closed)