Terraforming and being debt and at map border

[captain crunch]

Oddities about changing the landscape:
Raising or lowering land (5000¢) is not possible when being in debt, though it is possible to build artificial slopes which are more expensive (7500¢).
Building artificial slopes at the map's border is not possible, though it is possible to raise/lower land there.
What is the rationale of this?

[DrSuperGood]

Incomplete logic to stop abuse.

Debt is meant to be defined where your net wealth (sum of money and value of rolling stock) is less than 0. Everything that costs money should be impossible when you are in debt to stop possible abuse in multiplayer. The fact some actions still are possible is a bug.

[Dwachs]

While raising one tile is more expensive with artificial slopes, raising and lowering can affect multiple tiles. This check is there to prevent abuse in multiplayer games, where evil players lowered/raised land then went bankrupt

[prissi]

The thing about the sides was to prevent graphical errors. The slopes belong to the tile in front; but there ma be not tile in front. Artificial slopes would work with the relatively new slope view. Maybe that should go by now.