Blinking territory but not decaying

[elexis]

In this Alpha 21 replay provided by Imarok, the teal player has captured a farmstead at minute 10 that is connected to the orange players territory and thus didn't decay. However it has blinked the entire time until the player reached the next age.

(At minute 6 the teal player equally captured a farmstead at purple that was connected to that territory and never started blinking).

When trying to reproduce the issue, it is easily possible to build a house near an allies territory line without bordering it. (So it is expected to decay but doesn't).

[elexis]

Alpha 22 replay showing apparently disconnected houses not blinking nor decaying.

[elexis]

refs #4749

[elexis]

​Phab:D910

[elexis]

Someone should check wheather it was fixed by r20268.

[temple]

In 20949:

Add a tile owner check in territory decay

Differential Revision: ​https://code.wildfiregames.com/D1225
Reviewed By: mimo
Comment By: elexis
Fixes: #4787
Refs: #4681, #4749

[temple]

Territories can be adjacent diagonally, plus the boundary lines are curved so they don't extend all the way to the corner of a territory square. So it can look like two territories are disconnected even though they're actually connected, the same kind of issue as #1229.

[elexis]

disconnected not-decaying not-blinking house in the a22 replay

[elexis]

Blinking but not decaying connected farmstead in the a21 replay

[temple]

I tried removing the diagonal connections, but the boundary lines are smoothed (which is a good thing), so territories that are connected just by one tile can still appear to be disconnected. We'll need to make the boundary line algorithm smarter and more complicated to fix that.

Another issue is territories can be cut off from a root building, but if the player doesn't have a building in there to trigger a blinking check, it won't blink and he'll be able to place foundations until he finishes his first building and the territory finally starts to blink. This is a rare situation, but it can happen.