Gacha rework

Add fallback stripping and C6 stripping
Converting banner definitions from pity vars to lerp arrays
Properly implement rates and pool smoothing
Also move reusable functions to Utils

data/Banners.json

@@ -10,8 +10,9 @@
 		"beginTime": 0,
 		"endTime": 1924992000,
 		"sortId": 1000,
-		"rateUpItems1": [],
-		"rateUpItems2": []
+		"fallbackItems4Pool1": [1006, 1014, 1015, 1020, 1021, 1023, 1024, 1025, 1027, 1031, 1032, 1034, 1036, 1039, 1043, 1044, 1045, 1048, 1053, 1055, 1056, 1064],
+		"weights4": [[1,510], [8,510], [10,10000]],
+		"weights5": [[1,75], [73,150], [90,10000]]
 	},
 	{
 		"gachaType": 301,
@@ -24,9 +25,10 @@
 		"beginTime": 0,
 		"endTime": 1924992000,
 		"sortId": 9998,
-		"maxItemType": 1,
-		"rateUpItems1": [1002],
-		"rateUpItems2": [1053, 1020, 1045]
+		"rateUpItems4": [1053, 1020, 1045],
+		"rateUpItems5": [1002],
+		"fallbackItems5Pool2": [],
+		"weights5": [[1,80], [73,80], [90,10000]]
 	},
 	{
 		"gachaType": 302,
@@ -39,11 +41,12 @@
 		"beginTime": 0,
 		"endTime": 1924992000,
 		"sortId": 9997,
-		"minItemType": 2,
 		"eventChance": 75,
 		"softPity": 80,
 		"hardPity": 80,
-		"rateUpItems1": [11509, 12504],
-		"rateUpItems2": [11401, 12402, 13407, 14401, 15401]
+		"rateUpItems4": [11401, 12402, 13407, 14401, 15401],
+		"rateUpItems5": [11509, 12504],
+		"fallbackItems5Pool1": [],
+		"weights5": [[1,100], [62,100], [73, 7800], [80,10000]]
 	}
 ]

src/main/java/emu/grasscutter/game/gacha/GachaBanner.java

@@ -2,6 +2,7 @@ package emu.grasscutter.game.gacha;
 
 import emu.grasscutter.net.proto.GachaInfoOuterClass.GachaInfo;
 import emu.grasscutter.net.proto.GachaUpInfoOuterClass.GachaUpInfo;
+import emu.grasscutter.utils.Utils;
 
 import static emu.grasscutter.Configuration.*;
 
@@ -15,14 +16,31 @@ public class GachaBanner {
 	private int beginTime;
 	private int endTime;
 	private int sortId;
-	private int[] rateUpItems1;
-	private int[] rateUpItems2;
-	private int baseYellowWeight = 60; // Max 10000
-	private int basePurpleWeight = 510; // Max 10000
-	private int eventChance = 50; // Chance to win a featured event item
-	private int softPity = 75;
-	private int hardPity = 90;
+	private int[] rateUpItems4 = {};
+	private int[] rateUpItems5 = {};
+	private int[] fallbackItems3 = {11301, 11302, 11306, 12301, 12302, 12305, 13303, 14301, 14302, 14304, 15301, 15302, 15304};
+	private int[] fallbackItems4Pool1 = {1014, 1020, 1023, 1024, 1025, 1027, 1031, 1032, 1034, 1036, 1039, 1043, 1044, 1045, 1048, 1053, 1055, 1056, 1064};
+	private int[] fallbackItems4Pool2 = {11401, 11402, 11403, 11405, 12401, 12402, 12403, 12405, 13401, 13407, 14401, 14402, 14403, 14409, 15401, 15402, 15403, 15405};
+	private int[] fallbackItems5Pool1 = {1003, 1016, 1042, 1035, 1041};
+	private int[] fallbackItems5Pool2 = {11501, 11502, 12501, 12502, 13502, 13505, 14501, 14502, 15501, 15502};
+	private boolean removeC6FromPool = false;
+	private boolean autoStripRateUpFromFallback = true;
+	private int[][] weights4 = {{1,510}, {8,510}, {10,10000}};
+	private int[][] weights5 = {{1,75}, {73,150}, {90,10000}};
+	private int[][] poolBalanceWeights4 = {{1,255}, {17,255}, {21,10455}};
+	private int[][] poolBalanceWeights5 = {{1,30}, {147,150}, {181,10230}};
+	private int eventChance4 = 50; // Chance to win a featured event item
+	private int eventChance5 = 50; // Chance to win a featured event item
 	private BannerType bannerType = BannerType.STANDARD;
+
+	// Kinda wanna deprecate these but they're in people's configs
+	private int[] rateUpItems1 = {};
+	private int[] rateUpItems2 = {};
+	private int softPity = -1;
+	private int hardPity = -1;
+	private int eventChance = -1;
+	private int baseYellowWeight = -1;
+	private int basePurpleWeight = -1;
 	
 	public int getGachaType() {
 		return gachaType;
@@ -72,24 +90,42 @@ public class GachaBanner {
 		return basePurpleWeight;
 	}
 
-	public int[] getRateUpItems1() {
-		return rateUpItems1;
+	public int[] getRateUpItems4() {
+		return (rateUpItems2.length > 0) ? rateUpItems2 : rateUpItems4;
 	}
-
-	public int[] getRateUpItems2() {
-		return rateUpItems2;
+	public int[] getRateUpItems5() {
+		return (rateUpItems1.length > 0) ? rateUpItems1 : rateUpItems5;
 	}
-	
-	public int getSoftPity() {
-		return softPity - 1;
+
+	public int[] getFallbackItems3() {return fallbackItems3;}
+	public int[] getFallbackItems4Pool1() {return fallbackItems4Pool1;}
+	public int[] getFallbackItems4Pool2() {return fallbackItems4Pool2;}
+	public int[] getFallbackItems5Pool1() {return fallbackItems5Pool1;}
+	public int[] getFallbackItems5Pool2() {return fallbackItems5Pool2;}
+
+	public boolean getRemoveC6FromPool() {return removeC6FromPool;}
+	public boolean getAutoStripRateUpFromFallback() {return autoStripRateUpFromFallback;}
+
+
+	public int getWeight(int rarity, int pity) {
+		return switch(rarity) {
+			case 4 -> Utils.lerp(pity, weights4);
+			default -> Utils.lerp(pity, weights5);
+		};
 	}
 
-	public int getHardPity() {
-		return hardPity - 1;
+	public int getPoolBalanceWeight(int rarity, int pity) {
+		return switch(rarity) {
+			case 4 -> Utils.lerp(pity, poolBalanceWeights4);
+			default -> Utils.lerp(pity, poolBalanceWeights5);
+		};
 	}
 
-	public int getEventChance() {
-		return eventChance;
+	public int getEventChance(int rarity) {
+		return switch(rarity) {
+			case 4 -> eventChance4;
+			default -> (eventChance > -1) ? eventChance : eventChance5;
+		};
 	}
 
 	@Deprecated
@@ -131,10 +167,10 @@ public class GachaBanner {
 			info.setGachaTitlePath(this.getTitlePath());
 		}
 		
-		if (this.getRateUpItems1().length > 0) {
+		if (this.getRateUpItems5().length > 0) {
 			GachaUpInfo.Builder upInfo = GachaUpInfo.newBuilder().setItemParentType(1);
 			
-			for (int id : getRateUpItems1()) {
+			for (int id : getRateUpItems5()) {
 				upInfo.addItemIdList(id);
 				info.addMainNameId(id);
 			}
@@ -142,10 +178,10 @@ public class GachaBanner {
 			info.addGachaUpInfoList(upInfo);
 		}
 		
-		if (this.getRateUpItems2().length > 0) {
+		if (this.getRateUpItems4().length > 0) {
 			GachaUpInfo.Builder upInfo = GachaUpInfo.newBuilder().setItemParentType(2);
 			
-			for (int id : getRateUpItems2()) {
+			for (int id : getRateUpItems4()) {
 				upInfo.addItemIdList(id);
 				if (info.getSubNameIdCount() == 0) {
 					info.addSubNameId(id);

src/main/java/emu/grasscutter/game/gacha/GachaManager.java

@@ -29,6 +29,7 @@ import emu.grasscutter.net.proto.ItemParamOuterClass.ItemParam;
 import emu.grasscutter.server.game.GameServer;
 import emu.grasscutter.server.game.GameServerTickEvent;
 import emu.grasscutter.server.packet.send.PacketDoGachaRsp;
+import emu.grasscutter.utils.Utils;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
@@ -42,12 +43,6 @@ public class GachaManager {
 	private final Int2ObjectMap<GachaBanner> gachaBanners;
 	private GetGachaInfoRsp cachedProto;
 	WatchService watchService;
-
-	private final int[] yellowAvatars = new int[] {1003, 1016, 1042, 1035, 1041};
-	private final int[] yellowWeapons = new int[] {11501, 11502, 12501, 12502, 13502, 13505, 14501, 14502, 15501, 15502};
-	private final int[] purpleAvatars = new int[] {1006, 1014, 1015, 1020, 1021, 1023, 1024, 1025, 1027, 1031, 1032, 1034, 1036, 1039, 1043, 1044, 1045, 1048, 1053, 1055, 1056, 1064};
-	private final int[] purpleWeapons = new int[] {11401, 11402, 11403, 11405, 12401, 12402, 12403, 12405, 13401, 13407, 14401, 14402, 14403, 14409, 15401, 15402, 15403, 15405};
-	private final int[] blueWeapons = new int[] {11301, 11302, 11306, 12301, 12302, 12305, 13303, 14301, 14302, 14304, 15301, 15302, 15304};
 	
 	private static final int starglitterId = 221;
 	private static final int stardustId = 222;
@@ -66,24 +61,8 @@ public class GachaManager {
 	public Int2ObjectMap<GachaBanner> getGachaBanners() {
 		return gachaBanners;
 	}
-
-	public int[] getYellowAvatars() {
-		return this.yellowAvatars;
-	}
-	public int[] getYellowWeapons() {
-		return this.yellowWeapons;
-	}
-	public int[] getPurpleAvatars() {
-		return this.purpleAvatars;
-	}
-	public int[] getPurpleWeapons() {
-		return this.purpleWeapons;
-	}
-	public int[] getBlueWeapons() {
-		return this.blueWeapons;
-	}
-
-	public int randomRange(int min, int max) {
+	
+	public int randomRange(int min, int max) {  // Both are inclusive
 		return ThreadLocalRandom.current().nextInt(max - min + 1) + min;
 	}
 	
@@ -98,8 +77,14 @@ public class GachaManager {
 			if(banners.size() > 0) {
 				for (GachaBanner banner : banners) {
 					getGachaBanners().put(banner.getGachaType(), banner);
+					Grasscutter.getLogger().info(String.format("Testing lerp code for banner gachaType %d :", banner.getGachaType()));  // TODO: remove this before merging!
+					for (int i=1; i<91; i++) {
+						Grasscutter.getLogger().info(String.format("Pity %d : Weight %d", i, banner.getWeight(5, i)));
+					}
 				}
 				Grasscutter.getLogger().info("Banners successfully loaded.");
+
+
 				this.cachedProto = createProto();
 			} else {
 				Grasscutter.getLogger().error("Unable to load banners. Banners size is 0.");
@@ -109,6 +94,139 @@ public class GachaManager {
 			e.printStackTrace();
 		}
 	}
+
+	private class BannerPools {
+		public int[] rateUpItems4;
+		public int[] rateUpItems5;
+		public int[] fallbackItems4Pool1;
+		public int[] fallbackItems4Pool2;
+		public int[] fallbackItems5Pool1;
+		public int[] fallbackItems5Pool2;
+
+		public BannerPools(GachaBanner banner) {
+			rateUpItems4 = banner.getRateUpItems4();
+			rateUpItems5 = banner.getRateUpItems5();
+			fallbackItems4Pool1 = banner.getFallbackItems4Pool1();
+			fallbackItems4Pool2 = banner.getFallbackItems4Pool2();
+			fallbackItems5Pool1 = banner.getFallbackItems5Pool1();
+			fallbackItems5Pool2 = banner.getFallbackItems5Pool2();
+
+			if (banner.getAutoStripRateUpFromFallback()) {
+				fallbackItems4Pool1 = Utils.setSubtract(fallbackItems4Pool1, rateUpItems4);
+				fallbackItems4Pool2 = Utils.setSubtract(fallbackItems4Pool2, rateUpItems4);
+				fallbackItems5Pool1 = Utils.setSubtract(fallbackItems5Pool1, rateUpItems5);
+				fallbackItems5Pool2 = Utils.setSubtract(fallbackItems5Pool2, rateUpItems5);
+			}
+		}
+
+		public void removeFromAllPools(int[] itemIds) {
+			rateUpItems4 = Utils.setSubtract(rateUpItems4, itemIds);
+			rateUpItems5 = Utils.setSubtract(rateUpItems5, itemIds);
+			fallbackItems4Pool1 = Utils.setSubtract(fallbackItems4Pool1, itemIds);
+			fallbackItems4Pool2 = Utils.setSubtract(fallbackItems4Pool2, itemIds);
+			fallbackItems5Pool1 = Utils.setSubtract(fallbackItems5Pool1, itemIds);
+			fallbackItems5Pool2 = Utils.setSubtract(fallbackItems5Pool2, itemIds);
+		}
+	}
+
+	private synchronized int checkPlayerAvatarConstellationLevel(Player player, int itemId) {  // Maybe this would be useful in the Player class?
+		ItemData itemData = GameData.getItemDataMap().get(itemId);
+		if ((itemData == null) || (itemData.getMaterialType() != MaterialType.MATERIAL_AVATAR)){
+			return -2;  // Not an Avatar
+		}
+		Avatar avatar = player.getAvatars().getAvatarById((itemId % 1000) + 10000000);
+		if (avatar == null) {
+			return -1;  // Doesn't have
+		}
+		// Constellation
+		int constLevel = avatar.getCoreProudSkillLevel();
+		GameItem constItem = player.getInventory().getInventoryTab(ItemType.ITEM_MATERIAL).getItemById(itemId + 100);
+		constLevel += (constItem == null)? 0 : constItem.getCount();
+		return constLevel;
+	}
+
+	private synchronized int[] removeC6FromPool(int[] itemPool, Player player) {
+		IntList temp = new IntArrayList();
+		for (int itemId : itemPool) {
+			if (checkPlayerAvatarConstellationLevel(player, itemId) < 6) {
+				temp.add(itemId);
+			}
+		}
+		return temp.toIntArray();
+	}
+
+	private synchronized int drawRoulette(int[] weights, int cutoff) {
+		// This follows the logic laid out in issue #183
+		// Simple weighted selection with an upper bound for the roll that cuts off trailing entries
+		// All weights must be >= 0
+		int total = 0;
+		for (int i : weights) {
+			if (i < 0) {
+				throw new IllegalArgumentException("Weights must be non-negative!");
+			}
+			total += i;
+		}
+		int roll = ThreadLocalRandom.current().nextInt((total < cutoff)? total : cutoff);
+		int subTotal = 0;
+		for (int i : weights) {
+			subTotal += i;
+			if (roll < subTotal) {
+				return i;
+			}
+		}
+		// throw new IllegalStateException();
+		return 0;  // This should only be reachable if total==0
+	}
+
+	private synchronized int doRarePull(int[] featured, int[] fallback1, int[] fallback2, int rarity, GachaBanner banner, PlayerGachaBannerInfo gachaInfo) {
+		int itemId = 0;
+		if (	(featured.length > 0)
+				&& (gachaInfo.getFailedFeaturedItemPulls(rarity) >= 1)
+				|| (this.randomRange(1, 100) <= banner.getEventChance(rarity))) {
+			itemId = getRandom(featured);
+			gachaInfo.setFailedFeaturedItemPulls(rarity, 0);
+		} else {
+			gachaInfo.addFailedFeaturedItemPulls(rarity, 1);
+			if (fallback1.length < 1) {
+				itemId = getRandom(fallback2);  // Don't ever run an empty fallback2 btw
+			} else {
+				int pityPool1 = banner.getPoolBalanceWeight(rarity, gachaInfo.getPityPool(rarity, 1));
+				int pityPool2 = banner.getPoolBalanceWeight(rarity, gachaInfo.getPityPool(rarity, 2));
+				int chosenPool = switch ((pityPool1 >= pityPool2)? 1 : 0) {  // Larger weight must come first for the hard cutoff to function correctly
+					case 1 -> 1 + drawRoulette(new int[] {pityPool1, pityPool2}, 10000);
+					default -> 2 - drawRoulette(new int[] {pityPool2, pityPool1}, 10000);
+				};
+				itemId = switch (chosenPool) {
+					case 1:
+						gachaInfo.setPityPool(rarity, 1, 0);
+						yield getRandom(fallback1);
+					default:
+						gachaInfo.setPityPool(rarity, 2, 0);
+						yield getRandom(fallback2);
+				};
+			}
+		}
+		return itemId;
+	}
+
+	private synchronized int doPull(GachaBanner banner, PlayerGachaBannerInfo gachaInfo, BannerPools pools) {
+		// Pre-increment all pity pools (yes this makes all calculations assume 1-indexed pity)
+		gachaInfo.incPityAll();
+
+		int[] weights = {banner.getWeight(5, gachaInfo.getPity5()), banner.getWeight(4, gachaInfo.getPity4()), 10000};
+		int levelWon = 5 - drawRoulette(weights, 10000);
+
+		return switch (levelWon) {
+			case 5:
+				gachaInfo.setPity5(0);
+				yield doRarePull(pools.rateUpItems5, pools.fallbackItems5Pool1, pools.fallbackItems5Pool2, 5, banner, gachaInfo);
+			case 4:
+				gachaInfo.setPity4(0);
+				yield doRarePull(pools.rateUpItems4, pools.fallbackItems4Pool1, pools.fallbackItems4Pool2, 4, banner, gachaInfo);
+			default:
+				yield getRandom(banner.getFallbackItems3());
+		};
+	}
 	
 	public synchronized void doPulls(Player player, int gachaType, int times) {
 		// Sanity check
@@ -132,84 +250,27 @@ public class GachaManager {
 			return;
 		}
 		
-		// Roll
-		PlayerGachaBannerInfo gachaInfo = player.getGachaInfo().getBannerInfo(banner);
-		IntList wonItems = new IntArrayList(times);
-		
-		for (int i = 0; i < times; i++) {
-			int random = this.randomRange(1, 10000);
-			int itemId = 0;
-			
-			int bonusYellowChance = gachaInfo.getPity5() >= banner.getSoftPity() ? 100 * (gachaInfo.getPity5() - banner.getSoftPity() - 1): 0;
-			int yellowChance = banner.getBaseYellowWeight() + (int) Math.floor(100f * (gachaInfo.getPity5() / (banner.getSoftPity() - 1D))) + bonusYellowChance;
-			int purpleChance = 10000 - (banner.getBasePurpleWeight() + (int) Math.floor(790f * (gachaInfo.getPity4() / 8f)));
-		
-			if (random <= yellowChance || gachaInfo.getPity5() >= banner.getHardPity()) {
-				if (banner.getRateUpItems1().length > 0) {
-					int eventChance = this.randomRange(1, 100);
-					
-					if (eventChance <= banner.getEventChance() || gachaInfo.getFailedFeaturedItemPulls() >= 1) {
-						itemId = getRandom(banner.getRateUpItems1());
-						gachaInfo.setFailedFeaturedItemPulls(0);
-					} else {
-						// Lost the 50/50... rip
-						gachaInfo.addFailedFeaturedItemPulls(1);
-					}
-				}
-				
-				if (itemId == 0) {
-					int typeChance = this.randomRange(banner.getBannerType() == BannerType.WEAPON ? 2 : 1, banner.getBannerType() == BannerType.EVENT ? 1 : 2);
-					if (typeChance == 1) {
-						itemId = getRandom(this.yellowAvatars);
-					} else {
-						itemId = getRandom(this.yellowWeapons);
-					}
-				}
-
-				// Pity
-				gachaInfo.addPity4(1);
-				gachaInfo.setPity5(0);
-			} else if (random >= purpleChance || gachaInfo.getPity4() >= 9) {
-				if (banner.getRateUpItems2().length > 0) {
-					int eventChance = this.randomRange(1, 100);
-					
-					if (eventChance >= 50) {
-						itemId = getRandom(banner.getRateUpItems2());
-					}
-				}
-				
-				if (itemId == 0) {
-					int typeChance = this.randomRange(banner.getBannerType() == BannerType.WEAPON ? 2 : 1, banner.getBannerType() == BannerType.EVENT ? 1 : 2);
-					if (typeChance == 1) {
-						itemId = getRandom(this.purpleAvatars);
-					} else {
-						itemId = getRandom(this.purpleWeapons);
-					}
-				}
-				
-				// Pity
-				gachaInfo.addPity5(1);
-				gachaInfo.setPity4(0);
-			} else {
-				itemId = getRandom(this.blueWeapons);
-				
-				// Pity
-				gachaInfo.addPity4(1);
-				gachaInfo.addPity5(1);
-			}
-			
-			// Add winning item
-			wonItems.add(itemId);
-		}
-		
 		// Add to character
+		PlayerGachaBannerInfo gachaInfo = player.getGachaInfo().getBannerInfo(banner);
+		BannerPools pools = new BannerPools(banner);
 		List<GachaItem> list = new ArrayList<>();
 		int stardust = 0, starglitter = 0;
+
+		if (banner.getRemoveC6FromPool()) {  // The ultimate form of pity (non-vanilla)
+			pools.rateUpItems4 = removeC6FromPool(pools.rateUpItems4, player);
+			pools.rateUpItems5 = removeC6FromPool(pools.rateUpItems5, player);
+			pools.fallbackItems4Pool1 = removeC6FromPool(pools.fallbackItems4Pool1, player);
+			pools.fallbackItems4Pool2 = removeC6FromPool(pools.fallbackItems4Pool2, player);
+			pools.fallbackItems5Pool1 = removeC6FromPool(pools.fallbackItems5Pool1, player);
+			pools.fallbackItems5Pool2 = removeC6FromPool(pools.fallbackItems5Pool2, player);
+		}
 		
-		for (int itemId : wonItems) {
+		for (int i = 0; i < times; i++) {
+			// Roll
+			int itemId = doPull(banner, gachaInfo, pools);
 			ItemData itemData = GameData.getItemDataMap().get(itemId);
 			if (itemData == null) {
-				continue;
+				continue;  // Maybe we should bail out if an item fails instead of rolling the rest?
 			}
 
 			// Write gacha record
@@ -222,44 +283,33 @@ public class GachaManager {
 			boolean isTransferItem = false;
 			
 			// Const check
-			if (itemData.getMaterialType() == MaterialType.MATERIAL_AVATAR) {
-				int avatarId = (itemData.getId() % 1000) + 10000000;
-				Avatar avatar = player.getAvatars().getAvatarById(avatarId);
-				if (avatar != null) {
-					int constLevel = avatar.getCoreProudSkillLevel();
-					int constItemId = itemData.getId() + 100;
-					GameItem constItem = player.getInventory().getInventoryTab(ItemType.ITEM_MATERIAL).getItemById(constItemId);
-					if (constItem != null) {
-						constLevel += constItem.getCount();
+			int constellation = checkPlayerAvatarConstellationLevel(player, itemId);
+			switch (constellation) {
+				case -2:  // Is weapon
+					switch (itemData.getRankLevel()) {
+						case 5 -> addStarglitter = 10;
+						case 4 -> addStarglitter = 2;
+						default -> addStardust = 15;
 					}
-					
-					if (constLevel < 6) {
-						// Not max const
-						addStarglitter = 2;
-						// Add 1 const
+					break;
+				case -1:  // New character
+					gachaItem.setIsGachaItemNew(true);
+					break;
+				default:
+					if (constellation >= 6) {  // C6, give consolation starglitter
+						addStarglitter = (itemData.getRankLevel()==5)? 25 : 5;
+					} else {  // C0-C5, give constellation item
+						if (banner.getRemoveC6FromPool() && constellation == 5) {  // New C6, remove it from the pools so we don't get C7 in a 10pull
+							pools.removeFromAllPools(new int[] {itemId});
+						}
+						addStarglitter = (itemData.getRankLevel()==5)? 10 : 2;
+						int constItemId = itemId + 100;
+						GameItem constItem = player.getInventory().getInventoryTab(ItemType.ITEM_MATERIAL).getItemById(constItemId);
 						gachaItem.addTransferItems(GachaTransferItem.newBuilder().setItem(ItemParam.newBuilder().setItemId(constItemId).setCount(1)).setIsTransferItemNew(constItem == null));
 						player.getInventory().addItem(constItemId, 1);
-					} else {
-						// Is max const
-						addStarglitter = 5;
 					}
-					
-					if (itemData.getRankLevel() == 5) {
-						addStarglitter *= 5;
-					}
-					
 					isTransferItem = true;
-				} else {
-					// New
-					gachaItem.setIsGachaItemNew(true);
-				}
-			} else {
-				// Is weapon
-				switch (itemData.getRankLevel()) {
-					case 5 -> addStarglitter = 10;
-					case 4 -> addStarglitter = 2;
-					case 3 -> addStardust = 15;
-				}
+					break;
 			}
 
 			// Create item
@@ -272,7 +322,8 @@ public class GachaManager {
 			
 			if (addStardust > 0) {
 				gachaItem.addTokenItemList(ItemParam.newBuilder().setItemId(stardustId).setCount(addStardust));
-			} if (addStarglitter > 0) {
+			}
+			if (addStarglitter > 0) {
 				ItemParam starglitterParam = ItemParam.newBuilder().setItemId(starglitterId).setCount(addStarglitter).build();
 				if (isTransferItem) {
 					gachaItem.addTransferItems(GachaTransferItem.newBuilder().setItem(starglitterParam));
@@ -286,7 +337,8 @@ public class GachaManager {
 		// Add stardust/starglitter
 		if (stardust > 0) {
 			player.getInventory().addItem(stardustId, stardust);
-		} if (starglitter > 0) {
+		}
+		if (starglitter > 0) {
 			player.getInventory().addItem(starglitterId, starglitter);
 		}
 		

src/main/java/emu/grasscutter/game/gacha/PlayerGachaBannerInfo.java

@@ -7,6 +7,11 @@ public class PlayerGachaBannerInfo {
 	private int pity5 = 0;
 	private int pity4 = 0;
 	private int failedFeaturedItemPulls = 0;
+	private int failedFeatured4ItemPulls = 0;
+	private int pity5Pool1 = 0;
+	private int pity5Pool2 = 0;
+	private int pity4Pool1 = 0;
+	private int pity4Pool2 = 0;
 	
 	public int getPity5() {
 		return pity5;
@@ -32,15 +37,82 @@ public class PlayerGachaBannerInfo {
 		this.pity4 += amount;
 	}
 	
-	public int getFailedFeaturedItemPulls() {
-		return failedFeaturedItemPulls;
+	public int getFailedFeaturedItemPulls(int rarity) {
+		return switch (rarity) {
+			case 4 -> failedFeatured4ItemPulls;
+			default -> failedFeaturedItemPulls;  // 5
+		};
 	}
 	
-	public void setFailedFeaturedItemPulls(int failedEventCharacterPulls) {
-		this.failedFeaturedItemPulls = failedEventCharacterPulls;
+	public void setFailedFeaturedItemPulls(int rarity, int amount) {
+		switch (rarity) {
+			case 4 -> failedFeatured4ItemPulls = amount;
+			default -> failedFeaturedItemPulls = amount;  // 5
+		};
 	}
 	
-	public void addFailedFeaturedItemPulls(int amount) {
-		failedFeaturedItemPulls += amount;
+	public void addFailedFeaturedItemPulls(int rarity, int amount) {
+		switch (rarity) {
+			case 4 -> failedFeatured4ItemPulls += amount;
+			default -> failedFeaturedItemPulls += amount;  // 5
+		};
+	}
+	
+	public int getPityPool(int rarity, int pool) {
+		return switch (rarity) {
+			case 4 -> switch (pool) {
+				case 1 -> pity4Pool1;
+				default -> pity4Pool2;
+			};
+			default -> switch (pool) {
+				case 1 -> pity5Pool1;
+				default -> pity5Pool2;
+			};
+		};
+	}
+	
+	public void setPityPool(int rarity, int pool, int amount) {
+		switch (rarity) {
+			case 4:
+				switch (pool) {
+					case 1 -> pity4Pool1 = amount;
+					default -> pity4Pool2 = amount;
+				};
+				break;
+			case 5:
+			default:
+				switch (pool) {
+					case 1 -> pity5Pool1 = amount;
+					default -> pity5Pool2 = amount;
+				};
+				break;
+		};
+	}
+	
+	public void addPityPool(int rarity, int pool, int amount) {
+		switch (rarity) {
+			case 4:
+				switch (pool) {
+					case 1 -> pity4Pool1 += amount;
+					default -> pity4Pool2 += amount;
+				};
+				break;
+			case 5:
+			default:
+				switch (pool) {
+					case 1 -> pity5Pool1 += amount;
+					default -> pity5Pool2 += amount;
+				};
+				break;
+		};
+	}
+
+	public void incPityAll() {
+		pity4++;
+		pity5++;
+		pity4Pool1++;
+		pity4Pool2++;
+		pity5Pool1++;
+		pity5Pool2++;
 	}
 }

src/main/java/emu/grasscutter/utils/Utils.java

@@ -15,6 +15,8 @@ import emu.grasscutter.Grasscutter;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.Unpooled;
+import it.unimi.dsi.fastutil.ints.IntArrayList;
+import it.unimi.dsi.fastutil.ints.IntList;
 
 import org.slf4j.Logger;
 
@@ -314,4 +316,68 @@ public final class Utils {
         return String.format("%s-%s", locale.getLanguage(), locale.getCountry());
     }
 
+	/**
+	 * Performs a linear interpolation using a table of fixed points to create an effective piecewise f(x) = y function.
+	 * @param x
+	 * @param xyArray Array of points in [[x0,y0], ... [xN, yN]] format
+	 * @return f(x) = y
+	 */
+	public static int lerp(int x, int[][] xyArray) {
+		try {
+			if (x <= xyArray[0][0]){  // Clamp to first point
+				return xyArray[0][1];
+			} else if (x >= xyArray[xyArray.length-1][0]) {  // Clamp to last point
+				return xyArray[xyArray.length-1][1];
+			}
+			// At this point we're guaranteed to have two lerp points, and pity be somewhere between them.
+			for (int i=0; i < xyArray.length-1; i++) {
+				if (x == xyArray[i+1][0]) {
+					return xyArray[i+1][1];
+				}
+				if (x < xyArray[i+1][0]) {
+					// We are between [i] and [i+1], interpolation time!
+					// Using floats would be slightly cleaner but we can just as easily use ints if we're careful with order of operations. 
+					int position = x - xyArray[i][0];
+					int fullDist = xyArray[i+1][0] - xyArray[i][0];
+					int prevValue = xyArray[i][1];
+					int fullDelta = xyArray[i+1][1] - prevValue;
+					return prevValue + ( (position * fullDelta) / fullDist );
+				}
+			}
+		} catch (IndexOutOfBoundsException e) {
+			Grasscutter.getLogger().error("Malformed lerp point array. Must be of form [[x0, y0], ..., [xN, yN]].");
+		}
+		return 0;
+	}
+
+	/**
+	 * Checks if an int is in an int[]
+	 * @param key int to look for
+	 * @param array int[] to look in
+	 * @return key in array
+	 */
+	public static boolean intInArray(int key, int[] array) {
+		for (int i : array) {
+			if (i == key) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * Return a copy of minuend without any elements found in subtrahend.
+	 * @param minuend The array we want elements from
+	 * @param subtrahend The array whose elements we don't want
+	 * @return The array with only the elements we want, in the order that minuend had them
+	 */
+	public static int[] setSubtract(int[] minuend, int[] subtrahend) {
+		IntList temp = new IntArrayList();
+		for (int i : minuend) {
+			if (!intInArray(i, subtrahend)) {
+				temp.add(i);
+			}
+		}
+		return temp.toIntArray();
+	}
 }