[r6949] crash when building a bridge end on a stop

[whoami]

With rev.6949 Win-SDL, occurs with both pak64 and Pak128.Britain nightlies:
- build a straight piece of road
- build a bus stop on one end
- try to build a bridge that starts on the stop: crash
or
- try to build a bridge that ends on the stop: crash

EDIT: Also, it is possible to start a bridge from a tunnel entry tile, but not to have it end there. If the former is intended, then the latter should be allowed, too, IMO.

[Dwachs]

should be fixed

[whoami]

Yes, the crash is fixed, bridge heads on stops, tunnels and depots are now forbidden.
I see that (for stops and tunnel portals) the bridge head is moved to the next tile to start from there (sidenote: happens also for different waytypes), which is very nice and helpful. Yet I suggest to automatically connect the bridge to the adjacent way that the player had actually clicked on. It does not happen right now, it only looks like it does.

[prissi]

Under which curcumstances it fails? I tested a lot, and got connections.

[whoami]

Two screenshots from ST r6964 and pak654 r1336:
- picture 1: start building the bridge at the stop tile by dragging (without dragging, nothing happens, because that tile by itself is not valid).
- picture 2 shows that the bridge head is placed (automatically) onto the next tile, where it is allowed. Good.
- picture 2 also shows that the stop tile is not connected to the bridge. If the player is alert, s/he might see or remember that the connection has to be established, too. I suggest to create it automatically.
Same with bridges from tunnel entries, but the missing connection is not visible; it can be checked with the way remover tool or a convoy that needs that link.

[prissi]

This is the same as if you start dragging on the field next to the bridge. As such, simutrans cannot guess if you want a connection or not. You might just want ot have a stop on the bridge and never go down this way.

Just start draging to the right of the street will have the same result.

Simutrans may try to connect those, if it seems advantegeous. But it was left out intentionally.

[whoami]

I understand your point. But I referred specifically to the case where dragging the bridge starts on the tile with the stop (or tunnel). Okay, it may not happen often enough for special behaviour.

In general, the problem (also with the other cases) is mostly that the missing connection cannot be seen. This depends very much on the graphics (e.g. if a stop has a ground of its own).
Maybe another approach would help the player more (because it helps in more cases): make it easier to identify missing connections by visible means. The ground info window could show the ribis as graphics in addition to the text. Especially the new slopes make information about the steepness necessary, the gradient is not easy to see, and there is only one error message for the different reasons why a bridge or tunnel cannot be built. And/Or change the cursor according to ribis and slope.

[prissi]

It will only connect to tunnels if those are the endtiles, as the routine at its core is the same as the one for building bridges with single click.

Most easy is a default connection of the tile is on a slope, and the next tile too (when there is no visible indication). I will see to it.