City Trade Network disruption possible?

[dauphin]

This thread in General Discussion stirred my interest: The Underappreciated Navy

Apparently in Civ4 a naval blockade isn't possible anymore, since enemy units don't appear to disrupt the trade network (I tested this a little using the WorldBuilder).

For an in-land city the trading still could be blocked by pillaging the roads (unless the city is connected to the network by a river), but naturally the shoreline is always there.

Now I wonder if it would be possible to script that hostile units disrupt the trade network in their vincinity, but I don't even know where to start looking.

Btw, I don't refer to that a hostile unit hinders tiles to be worked on by citizens, that seems to work fine. I just think that such a blockade, whether by land or sea, would add some depth to the game (and give the navy something to do .

[CdGGambit]

I think enemy units still disrupt naval trade for that city, but if that city is connected to any other city (there own, or through open borders) which has an open harbor, than their shipments still come in.

[dauphin]

*shakes head* I cannot confirm this from what I've seen in my (admittedly limited) tests. If I detach (per Worldbuilder) the town from its road connections, and then spawn a hostile armada on its shore, it still is connected to the trade network (as can be seen by the icon, also neither resources vanish nor the foreign trade).

If I should have misunderstood something about this, please correct me.

[NP300]

I am disappointed if it is true that we can't blockade. It was supposed to be possible in Civ3, but the need to surround EVERY square made it impractical. I once did manage to blackade every square and nothing happened.

Anyway, hopefully we will be able to mod in blockades. It should be doable with only one ship in the city's range to make it viable. Airports should not count because they just can't carry the same amount of cargo that ships can carry.

[NP300]

Originally Posted by dauphin

This thread in General Discussion stirred my interest: The Underappreciated Navy

After reading the post, it occurs to me that a good method to make a navy worthwhile would be to have blockaded coastal cities lose a percentage of their commerce, hammers or food every turn. They could also be made to suffer reduced health or greater war weariness. Only one ship could blockade it. So now when the enemy parks a ship by your coastal city it is going to cost you gold per turn, perhaps a lower productivity in the city and maybe even starvation.

Now you would have a good incentive to protect your entire coast and not just want to maintain one trade link. With plain blockades you don't have an incentive to protect all coastal cities. You only need one lane open to get your oil. But with a gold/turn cost you would want to protect all the coastal cities. You could choose to not build a navy but it will cost you in gold or production. You may find yourself losing 100-200 gold per turn with several cities blockaded.

It could be very simple to implement:

IF enemy ship whithin city squares
THEN reduce city commerce by X%

Or it could be implemented with a "blockade" button on ships instead of having automatic blockades.

It may also be wise to allow blockades after a certain technology, such as with the advent of caravels or galleons and not earlier.

This whole idea would allow the implementation of privateers or state-sponsored piracy. You could build privateers, which could blockade a city without starting a war.

The greatest difficulty may be that the AI may need to be reprogrammed for this.

[dauphin]

That sounds very good, NP300. Together with water tiles that can't be worked on, an enemy ship before your coast would be pita. And yes, I see that AI problem too, even though the AI does maintain a navy normally.

Too bad I don't know Phyton.