Add failsafe at high slot counts.

Author: tinyhoot

SubnauticaRandomiser/Patches/EntitySlotsTrackerPatcher.cs

@@ -15,6 +15,9 @@ namespace SubnauticaRandomiser.Patches
     [HarmonyPatch]
     internal static class EntitySlotsTrackerPatcher
     {
+        private const float AdjustedSlotMult = 1.25f;
+        private const float SlotEmergencyThreshold = 0.95f;
+        
         private static EntitySlotsTrackerSaveData _saveData;
         private static ILogHandler _log = PrefixLogHandler.Get("[SlotTrackerPatcher]");
         private static IRandomHandler _rng = new RandomHandler();
@@ -127,17 +130,25 @@ private static EntitySlot.Filler GetForcedSpawn(BiomeType biome, EntitySlotData.
                 return default;
             // Pretend that more slots have spawned than really did so that we reach guaranteed 100% of entities spawned
             // *before* we run out of slots to do so.
-            slotProgress *= 1.25f; // Works out to 100% fragment saturation after 80% of slots have been processed.
-            
-            if (slotProgress < entityCounts.NextCheckThreshold)
+            var adjustedProgress = slotProgress * AdjustedSlotMult;
+            if (adjustedProgress < entityCounts.NextCheckThreshold)
                 return default;
 
-            var techType = entityCounts.GetForcedSpawn(slotProgress);
+            var techType = entityCounts.GetForcedSpawn(adjustedProgress);
             if (techType == TechType.None)
                 return default;
 
             _log.Debug($"Forcing spawn of '{techType}' in biome '{biome}'");
-            return new EntitySlot.Filler { classId = _saveData.Spawnables[techType].GetRandomPrefab(_rng), count = 1 };
+            int spawnCount = 1;
+            // If almost no slots are left do an emergency spawn where several entities are layered on top of each
+            // other. It's not pretty, but it prevents getting stuck / softlocked.
+            if (slotProgress >= SlotEmergencyThreshold)
+            {
+                spawnCount = entityCounts.GetNumMissingSpawns(techType);
+                _log.Warn($"Forcing emergency spawn of {spawnCount} {techType} in {biome}!");
+            }
+
+            return new EntitySlot.Filler { classId = _saveData.Spawnables[techType].GetRandomPrefab(_rng), count = spawnCount };
         }
     }
 }

SubnauticaRandomiser/Serialization/Modules/EntitySlots/EntityCounts.cs

@@ -26,13 +26,13 @@ public void AddEntity(TechType techType, int required)
         /// <summary>
         /// Count one successful spawn for an entity.
         /// </summary>
-        public void CountSpawn(TechType techType)
+        public void CountSpawn(TechType techType, int spawned = 1)
         {
             var counter = SpawnCounters.Find(c => c.TechType == techType);
             if (counter is null)
                 return;
 
-            counter.Add(1);
+            counter.Add(spawned);
             SortCounters();
             // Consider this biome completed when all minimum spawns have been reached.
             if (SpawnCounters[0].Spawned >= SpawnCounters[0].Required)
@@ -77,6 +77,20 @@ public TechType GetForcedSpawn(float completionThreshold)
             return counter.TechType;
         }
 
+        /// <summary>
+        /// Get the number of remaining spawns needed to satisfy the minimum spawn requirements of an entity.
+        /// </summary>
+        /// <exception cref="ArgumentException"></exception>
+        public int GetNumMissingSpawns(TechType entity)
+        {
+            var counter = SpawnCounters.Find(c => c.TechType == entity);
+            if (counter is null)
+                throw new ArgumentException($"No entity with TechType '{entity}' present in spawn counters!");
+
+            // Never return negatives.
+            return Mathf.Max(counter.Required - counter.Spawned, 0);
+        }
+
         [Serializable]
         internal class SpawnCounter
         {

SubnauticaRandomiser/Serialization/Modules/EntitySlots/EntitySlotsTrackerSaveData.cs

@@ -98,9 +98,8 @@ public void CountSpawnedEntity(BiomeType biome, EntitySlot.Filler filler)
             {
                 throw new KeyNotFoundException($"Filler classId '{filler.classId}' is not in WorldEntityDB!");
             }
-
-            var techType = info.techType;
-            counts.CountSpawn(techType);
+            
+            counts.CountSpawn(info.techType, filler.count);
         }
     }
 }