[Patch] Contextual construction information: cost, length and modifier hints

[prissi]

Oh my, the bridges and tunnel code was quite broken, never checked for bridges and tunnels if there was no an insurmountable obstacle. Also could not start on slopes. Also the double slope bug fixed.

Nor the inital city road builder does quite impressive routes through alpine terrain.

You may want to play with the values of the new parameters
way_tunnel=10
way_bridge=8

If this works, we can think of the next release ...

[Andarix]

....
If this works, we can think of the next release ...

Set up a tab and then cycle through the tabs.

[prissi]

That tool is not ready at all, but the way builder build on forbidden slopes was not ok.

That tool needs still a lot of work...

[makie]

That looks already very good.

Something isn't quite working right yet with bridges at double height differences. This works in version 2.5. See video. I don't know when that changed.
https://makie.de/dhb.webm
The video shows manual building. However, the Way builder don't build it that way either.

Set up a tab and then cycle through the tabs.

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Another video:
https://makie.de/dhb2.webm
Manually going over the embankment.
The WB refuses to build over the embankment and also over the DH slopes.

[prissi]

Double slopes cannot be a starting point for a bridges, since the way builder is not allowed to go there and test it. So it will start from the last accessible tile which is the flat tile before. Allowing this is tricky.

Building from vertical slopes is unlikely to be done by the way builder, as it normally does not construct those itself, and they would not occur in the game naturally.

About the images: There should be an empty image in the future, I mean an icon which means "no bridge" and "no tunnel".

Also the terraform flag should be separate from the rest. There is still plenty of work, this was mean as a first try. I still wonder, if it should not look like a toolbar, first icon tool, second icon way, third icon bridge, tunnel, and then flags as icons.