The problem we had before was this:
* All borders were drawn.
* Border information was only given for visible tiles.
* The end result was that you couldn't see many tiles that you owned,
causing a massive patchwork of borders within your own territory as
you re-explored it.
* Also when an enemy city changed hands and you re-explored that
territory, it would cause a similar patchwork. It would be obvious to
the player that a city was owned by the enemy but the display wouldn't
know it yet since that tile hadn't been re-explored.
There might be some way around this by clever adjustments to the
display algorithm. For instance ptile->source could give the border
source so any time a player discovered a changed tile the player map
would toggle that city's owner and all borders owned by it. All
borders would then be done in clumps rather than tile-by-tile.
Another idea of course is to give full vision to tiles you own, which
does indeed make plenty of sense - though it does not prevent enemies
from finding your borders invisibly, as they don't have to enter your
territory to see it. Yet another idea would be to give passive
updates to tiles you own (keeping it fogged but re-updating all
information, I believe this is the update_tile_knowledge() function or
some such). This would prevent any patchwork issues on your own
borders as you'd know about them expanding even though the tile was
Some combination of these could be better than what we have now. But
any new design must be thought out and then carefully playtested.
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