Thanks for testing.
If you get the results your screenshot is showing you must have disabled natural direction in the settings. This is exactly what I mean when forward/backward is used it’s the opposite rule to a degree value, which is why I think it’s best to handle it the same way with natural direction. To change the backward/forward areas and way pointing would be much more confusing. You would point in the forward direction of the sign and would get backward as direction. You obviously know how to map, so you see it opposite because for you the front side of the sign is the thing to look at. For those who know exactly what they are doing I’ve added the option to disable natural direction to so you are able to do it knowing that you have to point to the other direction, but for ways it’s still based on the rule of the travelling traffic.
I would suggest to get used to the natural option, in the end it’s a lot easier that way because you just have to take the direction of the travelling traffic into account. Previously I’ve mapped it the other way around but it needed a lot of concentration to get it right every time, when mapping a huge data set. Now I just need to point to the affected part of the way and it will be right and with the popup menu I get a visual hint which part of a way will be affected by the sign I’m mapping.
I see it different for traffic signals also. The signal will always regulate the traffic behind the signal not before. The traffic is coming to a halt before the signal, but that is not the reason why the signal is there, it is there to regulate the traffic at the intersection. It’s the same like a STOP sign. It will cause the traffic to stop at the sign, but it regulates the intersection behind it.
Typically no traffic sign will regulate anything before the sign. There are some special cases like the German VZ 240 with the additional sign VZ 1000-30 which are sometimes placed in a 90° angle of a shared foot and bicycle way, so this combination regulates left and right before the sign. But some things are just impossible to handle automatically. At the end the user will have to know what to do.
With the newest version you will get the popup menu for each node of a way that has a traffic sign and the direction is missing or is ambiguous. The easiest to test is with two ways and a traffic sign at the intersection. The ways don’t have to be separated anymore to see which way part is affected by the sign. The way segment will be highlighted for each degree value that is hovered over with the mouse.
I’ve been using a highly altered version of JOSM which is based on an older version, so there might be some changes that cause the error. I will look into it.