Document floorProps->enemyDensity bug

include/structs/str_dungeon.h

@@ -120,12 +120,12 @@ typedef struct UnkDungeonGlobal_unk181E8_sub
 typedef struct FloorProperties
 {
     u8 layout;
-    s8 roomDensity;
+    s8 roomDensity; // If positive, allow variance. If negative, use exact value of abs(roomDensity).
     u8 tileset;
     u8 bgMusic;
     u8 weather; // Uses the weather constants in weather.h.
     u8 floorConnectivity;
-    u8 enemyDensity;
+    u8 enemyDensity; // Game treats this as signed. See SpawnEnemies in src/dungeon_generation.asm for details.
     u8 kecleonShopChance; // Percentage chance 0-100%
     u8 monsterHouseChance; // Percentage chance 0-100%
     u8 mazeRoomChance; // Percentage chance 0-100%

src/dungeon_generation.c

@@ -4423,6 +4423,9 @@ static void SpawnEnemies(FloorProperties *floorProps, bool8 isEmptyMonsterHouse)
     s32 numEnemies, numMonsterHouseEnemies;
     s32 enemyDensity = floorProps->enemyDensity;
 
+    // BUG: Game assumes floorProps->enemyDensity is a signed byte, but in reality it's unsigned.
+    // Attempting to use a negative density will instead produce a very large positive density up to 255. 
+    // This only matters for unused dungeons, as Deoxys has its own logic despite Meteor Cave having an effective enemy density of 255.
 	if (enemyDensity > 0) {
 		// Positive means value with variance
 		numEnemies = DungeonRandRange(enemyDensity / 2, enemyDensity);