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VariableVince
11e183366f
## Description: An inverse annexation could happen where the small player (even with 0,01% tiles owned) could fully annex the large player. **TL;DR:** basically wrong use of calculateBoundingBox in surroundedBySamePlayer, feeding it all bordertiles, making enemyBox far bigger than it actually was in some cases. Which resulted in enemyBox of small player with two small clusters at some distance from each other, being seen as inscribing the largest cluster of the bigger player. While that largest cluster is actually the border tiles of the bigger player surrounding the main cluster of the small player. Instead of an annexation of small by bigger, small would incorrectly annex bigger completely. **Situation:** bigger player fully surrounds main cluster of smaller player. Those border tiles are also the largest cluster of the bigger player, for which surroundedBySamePlayer is called. SurroundedBySamePlayer finds the small player as the only bordering enemy of this cluster. Then it needs to check which of the two players is surrounded by the other one. EnemyBox uses calculateBoundingBox with all border tiles of the small player as argument. The small player also has at least one seperate cluster elsewhere, could be on another island, which count as border tiles too. The enemyBox from the main cluster of the small player to the seperate cluster elsewhere, can be huge. Now inscribed() is called and it determines that largest cluster box of the bigger player (which was in fact calculated correctly, also making use of calculateBoundingBox) is surrounded by the bigger enemyBox. And so the small surrounded player fully annexes the bigger player. **Fix:** instead of a global enemyBox, we only need the localEnemyBox that touches the largest cluster of the bigger player. With that, inscribed() can correctly conclude that largest cluster box surrounds the localEnemyBox. As a matter of fact isSurrounded() already used the same method to calculate its enemyBox as introduced by @scamiv for v30: https://github.com/openfrontio/OpenFrontIO/pull/3127/changes#diff-fb1101a2b50dd7c353d082ff7a3351cff5469b8249b3ebca91c10573a3dfaaf1 - Change in PlayerExecution - Added test NoInverseAnnexation.test.ts, which fails before and passes after the fix The bug was introduced in this commit 10 months ago: https://github.com/openfrontio/OpenFrontIO/commit/c4381a9ad3828b06764ab1a21fc1514e37aacfd7 It has probably led to some weird annexations happening since then. The bug could seemingly happen on any map. But was noted recently a few times on square islands (Sierpinski) or maps (The Box/The Alps), where the circumstances probably highten the chances of the bug occuring. **Bug reports:** https://discord.com/channels/1359946986937258015/1481916231689703477/1481916231689703477 https://discord.com/channels/1359946986937258015/1481916231689703477/1481963273367851030 https://discord.com/channels/1284581928254701718/1479993924432171008/1479995658302652496 https://discord.com/channels/1284581928254701718/1479993924432171008/1481865495492956182 https://discord.com/channels/1284581928254701718/1483047153571201034 **BEFORE:** https://github.com/user-attachments/assets/4440182b-f696-45cf-bb01-b10159df8763 **AFTER**, on the same replay but with the bugfix: https://github.com/user-attachments/assets/5f461ab2-eb62-4cc3-ae07-e2224adbbc6a ## Please complete the following: - [x] I have added screenshots for all UI updates - [x] I process any text displayed to the user through translateText() and I've added it to the en.json file - [x] I have added relevant tests to the test directory - [x] I confirm I have thoroughly tested these changes and take full responsibility for any bugs introduced ## Please put your Discord username so you can be contacted if a bug or regression is found: tryout33