Restore Legacy link modifier travel behavior

docs/GAMETESTS.md

@@ -85,8 +85,9 @@ With optional JEI installed, search for the Ink Mixer category. It should show
 the base paper/ink/vial operation and separate entries for Gunpowder, Mushroom
 Stew, Experience Bottle, Ender Pearl, Feather, and Fire Charge,
 with their property chances. Black Dye and Clay Ball should not appear: the
-former had no working Legacy effect, while Generate Platform is redundant
-with default Age arrival. Without JEI, Rivencraft should still
+former had no working Legacy effect, while Clay Ball remains unsupported by
+the mixer. The creative Link Modifier can enable a single arrival platform for
+Linking Books; they do not create one by default. Without JEI, Rivencraft should still
 start and the mixer should work normally.
 
 Put paper and an Ink Vial in the mixer. Hold Gunpowder on the cursor and

docs/INK_MIXER_MODIFIER_AUDIT.md

@@ -27,4 +27,4 @@ Implementation requirements: keep the mixer server-authoritative; persist mixtur
 
 The built-in vanilla-item rows above are supported except black dye and clay balls. Legacy ignores black dye's empty effect key, so Rivencraft does not consume or advertise it in JEI. Clay Balls are omitted because Age arrival already builds a safe platform by default and a separate Generate Platform link modifier would be redundant. Right-clicking the Ink Mixer basin with a carried item adds one; left-clicking adds the carried stack. The mixture is persistent and its next panel is deterministic. The visual basin tooltip shows current probabilities. Only taking the virtual Link Panel consumes paper/ink and clears the mixture. The Link Panel's property component is copied to a Linking Book by the leather recipe or a Descriptive Book by the Binder. JEI's optional Ink Mixer category lists the base panel and each supported additive interaction with its per-property chance; Rivencraft does not require JEI to run.
 
-Disarm and Maintain Momentum are applied by the server after confirming a safe destination. Disarm spawns each inventory stack as an item entity at the departure point, including for Descriptive Books. Intra Linking is required only for a Linking Book whose destination is in the player's current dimension; ordinary cross-dimensional Linking Books still work. The Binder treats an Intra Linking panel as an ordinary Link Panel and omits that flag from the resulting Descriptive Book, while retaining Disarm and Maintain Momentum. Automatic Return Links remain enabled under the existing configuration, as requested. The old Generate Platform bit remains readable on pre-0.4.7.1 test items but is neither rolled nor applied. Optional dust-tag mappings remain outside this built-in subset until their cross-mod tags and gameplay meaning are agreed.
+Disarm and Maintain Momentum are applied by the server after confirming a safe destination. Disarm spawns each inventory stack as an item entity at the departure point, including for Descriptive Books. Intra Linking is required only for a Linking Book whose destination is in the player's current dimension; ordinary cross-dimensional Linking Books still work. The Binder treats an Intra Linking panel as an ordinary Link Panel and omits that flag from the resulting Descriptive Book, while retaining Disarm and Maintain Momentum. Automatic Return Links remain enabled under the existing configuration, as requested. The Ink Mixer still does not roll Generate Platform, but since 0.6.7.1 the creative Link Modifier can explicitly enable it for Linking Books; their default remains off. Optional dust-tag mappings remain outside this built-in subset until their cross-mod tags and gameplay meaning are agreed.

gradle.properties

@@ -36,7 +36,7 @@ mod_name=Rivencraft
 # The license of the mod. Review your options at https://choosealicense.com/. All Rights Reserved is the default.
 mod_license=LGPL-3.0-or-later
 # The mod version. Rivencraft uses the x.y.z.b policy documented in README.md.
-mod_version=0.6.7.0
+mod_version=0.6.7.1
 immersive_portals_version=6.0.7
 terrablender_version=4.1.0.8
 serene_seasons_version_id=pHEgQQUE

src/main/java/net/dnorberg/rivencraft/block/CrystalPortalBlock.java

@@ -11,7 +11,6 @@ import net.dnorberg.rivencraft.registry.ModItems;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.server.level.ServerLevel;
-import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.util.RandomSource;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
@@ -54,16 +53,16 @@ public final class CrystalPortalBlock extends BaseEntityBlock {
     @Override protected boolean canBeReplaced(BlockState state, Fluid fluid) { return false; }
 
     @Override protected void entityInside(BlockState state, Level level, BlockPos pos, Entity entity) {
-        if (!(level instanceof ServerLevel server) || !(entity instanceof ServerPlayer player)) return;
+        if (!(level instanceof ServerLevel server)) return;
         long now = server.getServer().getTickCount();
-        if (PortalTravelCooldown.blocked(player, now)) return;
+        if (PortalTravelCooldown.blocked(entity, now)) return;
         if (!(level.getBlockEntity(pos) instanceof CrystalPortalBlockEntity portal)
                 || portal.receptacle() == null || !level.hasChunkAt(portal.receptacle())
                 || !(level.getBlockEntity(portal.receptacle()) instanceof BookReceptacleBlockEntity holder)) return;
         ItemStack book = holder.getBook();
         if (book.isEmpty()) return;
-        PortalTravelCooldown.mark(player, now);
-        PortalTravelQueue.enqueue(player, server, pos, portal.receptacle(), book, now);
+        PortalTravelCooldown.mark(entity, now);
+        PortalTravelQueue.enqueue(entity, server, pos, portal.receptacle(), book, now);
     }
 
     @Override protected void neighborChanged(BlockState state, Level level, BlockPos pos, Block neighbor,

src/main/java/net/dnorberg/rivencraft/book/AgeDimensionService.java

@@ -101,9 +101,14 @@ public final class AgeDimensionService {
 
     public static Optional<LinkTarget> resolve(ServerPlayer player, AgeReference reference,
                                                 OrderedWriting writing, boolean generatePlatform) {
-        AgeDefinition definition = AgeRegistrySavedData.resolveOrCreate(player.serverLevel(), reference, writing);
-        if (AgeRegistrySavedData.get(player.serverLevel()).isDead(definition.id())) return Optional.empty();
-        ServerLevel level = ensureLoaded(player.getServer(), definition);
+        return resolve(player.serverLevel(), reference, writing, generatePlatform);
+    }
+
+    public static Optional<LinkTarget> resolve(ServerLevel source, AgeReference reference,
+                                               OrderedWriting writing, boolean generatePlatform) {
+        AgeDefinition definition = AgeRegistrySavedData.resolveOrCreate(source, reference, writing);
+        if (AgeRegistrySavedData.get(source).isDead(definition.id())) return Optional.empty();
+        ServerLevel level = ensureLoaded(source.getServer(), definition);
         if (level == null) {
             return Optional.empty();
         }

src/main/java/net/dnorberg/rivencraft/book/LinkDisarmService.java

@@ -0,0 +1,58 @@
+package net.dnorberg.rivencraft.book;
+
+import net.dnorberg.rivencraft.mixin.MobDropChanceAccessor;
+import net.minecraft.world.Container;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.entity.EquipmentSlot;
+import net.minecraft.world.entity.Mob;
+import net.minecraft.world.entity.animal.horse.AbstractHorse;
+import net.minecraft.world.entity.item.ItemEntity;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.item.ItemStack;
+
+/** Legacy-style Disarm: leave carried items and eligible equipment at the departure point. */
+public final class LinkDisarmService {
+    private LinkDisarmService() {}
+
+    public static boolean mayTravel(Entity entity) {
+        // Legacy refuses loose items and dropped Link Books on Disarm links.
+        return !(entity instanceof ItemEntity);
+    }
+
+    public static void disarm(Entity entity) {
+        if (entity instanceof ServerPlayer player) {
+            eject(player, player.getInventory());
+            player.containerMenu.broadcastChanges();
+        }
+        if (entity instanceof Container container) eject(entity, container);
+        if (entity instanceof AbstractHorse horse) eject(entity, horse.getInventory());
+        if (entity instanceof Mob mob) dropEquipment(mob);
+    }
+
+    private static void eject(Entity carrier, Container inventory) {
+        for (int slot = 0; slot < inventory.getContainerSize(); slot++) {
+            ItemStack stack = inventory.getItem(slot);
+            if (stack.isEmpty()) continue;
+            inventory.setItem(slot, ItemStack.EMPTY);
+            carrier.spawnAtLocation(stack);
+        }
+        inventory.setChanged();
+    }
+
+    private static void dropEquipment(Mob mob) {
+        for (EquipmentSlot slot : EquipmentSlot.values()) {
+            ItemStack stack = mob.getItemBySlot(slot);
+            if (stack.isEmpty()) continue;
+            float chance = ((MobDropChanceAccessor) mob).rivencraft$getEquipmentDropChance(slot);
+            mob.setItemSlot(slot, ItemStack.EMPTY);
+            if (chance <= 0 || mob.getRandom().nextFloat() >= chance) continue;
+            if (chance <= 1 && stack.isDamageableItem()) {
+                int minimum = Math.max(stack.getMaxDamage() - 25, 1);
+                int damage = stack.getMaxDamage() - mob.getRandom().nextInt(
+                        1 + mob.getRandom().nextInt(minimum));
+                stack.setDamageValue(Math.clamp(damage, 1, minimum));
+            }
+            mob.spawnAtLocation(stack);
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/book/LinkModifierBehaviorGameTests.java

@@ -0,0 +1,125 @@
+package net.dnorberg.rivencraft.book;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.GlobalPos;
+import net.minecraft.gametest.framework.GameTest;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.world.entity.EquipmentSlot;
+import net.minecraft.world.entity.EntityType;
+import net.minecraft.world.entity.animal.horse.Donkey;
+import net.minecraft.world.entity.item.ItemEntity;
+import net.minecraft.world.entity.monster.Zombie;
+import net.minecraft.world.entity.vehicle.MinecartChest;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.Items;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.phys.AABB;
+import net.minecraft.world.phys.Vec3;
+import net.neoforged.neoforge.gametest.GameTestHolder;
+import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
+
+@GameTestHolder(Rivencraft.MOD_ID)
+@PrefixGameTestTemplate(false)
+public final class LinkModifierBehaviorGameTests {
+    private LinkModifierBehaviorGameTests() {}
+
+    @GameTest(template = "empty")
+    public static void maintainMomentumRotatesToDestinationYaw(GameTestHelper helper) {
+        Vec3 result = LinkingService.rotatedMomentum(new Vec3(3, -0.5, 4), 90);
+        helper.assertTrue(Math.abs(result.x) < 0.0001 && Math.abs(result.y + 0.3) < 0.0001
+                        && Math.abs(result.z - 5) < 0.0001,
+                "Legacy momentum preserves horizontal speed, rotates to destination yaw, and adds a small lift");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void disarmRefusesLooseItems(GameTestHelper helper) {
+        var level = helper.getLevel();
+        ItemEntity item = new ItemEntity(level, 1, 1, 1, new ItemStack(Items.DIAMOND));
+        level.addFreshEntity(item);
+        LinkTarget target = new LinkTarget(GlobalPos.of(level.dimension(), helper.absolutePos(new BlockPos(2, 1, 2))),
+                0, 0);
+        helper.assertValueEqual(LinkingService.travelEntityPortal(item, target,
+                        new LinkProperties(LinkProperties.DISARM | LinkProperties.INTRA_LINKING), false),
+                LinkingService.LinkResult.DISARM_REJECTED,
+                "Legacy Disarm must refuse a loose item before teleportation");
+        helper.assertTrue(item.isAlive() && item.getItem().is(Items.DIAMOND),
+                "Rejected item must remain at the source");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void ordinaryLinkMovesLooseItemWithoutMakingPlatform(GameTestHelper helper) {
+        var level = helper.getLevel();
+        BlockPos landing = helper.absolutePos(new BlockPos(2, 2, 2));
+        level.setBlock(landing.below(), Blocks.AIR.defaultBlockState(), 2);
+        level.setBlock(landing, Blocks.AIR.defaultBlockState(), 2);
+        level.setBlock(landing.above(), Blocks.AIR.defaultBlockState(), 2);
+        ItemEntity item = new ItemEntity(level, 1, 1, 1, new ItemStack(Items.DIAMOND));
+        level.addFreshEntity(item);
+        LinkTarget target = new LinkTarget(GlobalPos.of(level.dimension(), landing), 0, 0);
+        helper.assertValueEqual(LinkingService.travelEntityPortal(item, target,
+                        new LinkProperties(LinkProperties.INTRA_LINKING), false),
+                LinkingService.LinkResult.SUCCESS, "Ordinary portal links may carry loose items");
+        helper.assertTrue(item.blockPosition().distManhattan(landing) <= 1,
+                "Item must arrive at the linked location");
+        helper.assertTrue(level.getBlockState(landing.below()).isAir(),
+                "A Linking Book must not generate a landing platform by default");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void explicitGeneratePlatformAddsOnlyArrivalFloor(GameTestHelper helper) {
+        var level = helper.getLevel();
+        BlockPos landing = helper.absolutePos(new BlockPos(2, 2, 2));
+        level.setBlock(landing.below(), Blocks.AIR.defaultBlockState(), 2);
+        level.setBlock(landing, Blocks.AIR.defaultBlockState(), 2);
+        level.setBlock(landing.above(), Blocks.AIR.defaultBlockState(), 2);
+        level.setBlock(landing.above(2), Blocks.AIR.defaultBlockState(), 2);
+        ItemEntity item = new ItemEntity(level, 1, 1, 1, new ItemStack(Items.DIAMOND));
+        level.addFreshEntity(item);
+        LinkTarget target = new LinkTarget(GlobalPos.of(level.dimension(), landing), 0, 0);
+        helper.assertValueEqual(LinkingService.travelEntityPortal(item, target,
+                        new LinkProperties(LinkProperties.INTRA_LINKING | LinkProperties.GENERATE_PLATFORM), false),
+                LinkingService.LinkResult.SUCCESS, "An explicit platform link must travel");
+        helper.assertTrue(level.getBlockState(landing.below()).is(
+                        net.dnorberg.rivencraft.registry.ModBlocks.CLOUD_PLATFORM.get()),
+                "An enabled Linking Book platform must add one cloud block below the arrival");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void disarmEmptiesCarrierAndMobEquipment(GameTestHelper helper) {
+        var level = helper.getLevel();
+        Vec3 source = Vec3.atCenterOf(helper.absolutePos(new BlockPos(1, 1, 1)));
+        MinecartChest cart = EntityType.CHEST_MINECART.create(level);
+        Donkey donkey = EntityType.DONKEY.create(level);
+        Zombie zombie = EntityType.ZOMBIE.create(level);
+        helper.assertTrue(cart != null && donkey != null && zombie != null, "Carriers must instantiate");
+        cart.setPos(source);
+        donkey.setPos(source);
+        zombie.setPos(source);
+        level.addFreshEntity(cart);
+        level.addFreshEntity(donkey);
+        level.addFreshEntity(zombie);
+        cart.setItem(0, new ItemStack(Items.EMERALD));
+        donkey.getInventory().setItem(0, new ItemStack(Items.SADDLE));
+        zombie.setItemSlot(EquipmentSlot.MAINHAND, new ItemStack(Items.IRON_SWORD));
+        zombie.setDropChance(EquipmentSlot.MAINHAND, 2.0F);
+
+        LinkDisarmService.disarm(cart);
+        LinkDisarmService.disarm(donkey);
+        LinkDisarmService.disarm(zombie);
+
+        helper.assertTrue(cart.getItem(0).isEmpty() && donkey.getInventory().getItem(0).isEmpty()
+                        && zombie.getItemBySlot(EquipmentSlot.MAINHAND).isEmpty(),
+                "Disarm must remove inventory contents and worn equipment");
+        var drops = level.getEntitiesOfClass(ItemEntity.class, new AABB(source, source).inflate(3));
+        helper.assertTrue(drops.stream().anyMatch(item -> item.getItem().is(Items.EMERALD))
+                        && drops.stream().anyMatch(item -> item.getItem().is(Items.SADDLE))
+                        && drops.stream().anyMatch(item -> item.getItem().is(Items.IRON_SWORD)),
+                "Carrier items and guaranteed-drop mob equipment must remain at departure");
+        helper.succeed();
+    }
+}

src/main/java/net/dnorberg/rivencraft/book/LinkProperties.java

@@ -11,7 +11,7 @@ import net.minecraft.network.chat.Component;
 /** Flags written into a Link Panel and carried by books assembled from it. */
 public record LinkProperties(int flags) {
     public static final int DISARM = 1;
-    /** Retained to read older test books; a newly edited book uses DISABLE_PLATFORM instead. */
+    /** Linking Books do not create a platform unless this Legacy flag is enabled. */
     public static final int GENERATE_PLATFORM = 2;
     public static final int MAINTAIN_MOMENTUM = 4;
     public static final int INTRA_LINKING = 8;
@@ -48,6 +48,7 @@ public record LinkProperties(int flags) {
         if (has(INTRA_LINKING)) lines.add(propertyName("intra_linking"));
         if (has(INTRA_LINKING_ONLY)) lines.add(propertyName("intra_linking_only"));
         if (has(RELATIVE_LINK)) lines.add(propertyName("relative_link"));
+        if (has(GENERATE_PLATFORM)) lines.add(propertyName("generate_platform"));
         if (has(DISABLE_PLATFORM)) lines.add(propertyName("disable_platform"));
     }
 
@@ -63,6 +64,7 @@ public record LinkProperties(int flags) {
             case INTRA_LINKING -> propertyName("intra_linking");
             case INTRA_LINKING_ONLY -> propertyName("intra_linking_only");
             case RELATIVE_LINK -> propertyName("relative_link");
+            case GENERATE_PLATFORM -> propertyName("generate_platform");
             case DISABLE_PLATFORM -> propertyName("disable_platform");
             default -> throw new IllegalArgumentException("Unknown link property flag: " + flag);
         };

src/main/java/net/dnorberg/rivencraft/book/LinkingService.java

@@ -6,16 +6,20 @@ import java.util.stream.IntStream;
 import java.util.stream.Stream;
 import net.dnorberg.rivencraft.compat.ImmersivePortalsChunkLoaders;
 import net.dnorberg.rivencraft.entity.DroppedBookEntity;
+import net.dnorberg.rivencraft.portal.PortalTravelCooldown;
+import net.dnorberg.rivencraft.registry.ModBlocks;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.InteractionHand;
+import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.tags.BlockTags;
 import net.minecraft.world.level.border.WorldBorder;
 import net.minecraft.world.level.levelgen.Heightmap;
 import net.minecraft.world.phys.Vec3;
+import net.minecraft.world.level.portal.DimensionTransition;
 import net.neoforged.fml.ModList;
 
 /** Server-side validation and execution for book travel. */
@@ -96,9 +100,9 @@ public final class LinkingService {
 
         Vec3 position = destination.get();
         Vec3 momentum = player.getDeltaMovement();
-        if (properties.has(LinkProperties.DISARM)) dropInventoryAtSource(player);
+        if (properties.has(LinkProperties.DISARM)) LinkDisarmService.disarm(player);
         teleport(player, destinationLevel, position, target, true);
-        if (properties.has(LinkProperties.MAINTAIN_MOMENTUM)) player.setDeltaMovement(momentum);
+        applyMomentum(player, momentum, target, properties);
         player.resetFallDistance();
         return LinkResult.SUCCESS;
     }
@@ -114,9 +118,9 @@ public final class LinkingService {
                 landingOrigin(player, destinationLevel, target, properties), true);
         if (destination.isEmpty()) return LinkResult.NO_SAFE_DESTINATION;
         Vec3 momentum = player.getDeltaMovement();
-        if (properties.has(LinkProperties.DISARM)) dropInventoryAtSource(player);
+        if (properties.has(LinkProperties.DISARM)) LinkDisarmService.disarm(player);
         teleport(player, destinationLevel, destination.get(), target, instant);
-        if (properties.has(LinkProperties.MAINTAIN_MOMENTUM)) player.setDeltaMovement(momentum);
+        applyMomentum(player, momentum, target, properties);
         player.resetFallDistance();
         return LinkResult.SUCCESS;
     }
@@ -142,36 +146,80 @@ public final class LinkingService {
 
         Vec3 position = destination.get();
         Vec3 momentum = player.getDeltaMovement();
-        if (properties.has(LinkProperties.DISARM)) dropInventoryAtSource(player);
+        if (properties.has(LinkProperties.DISARM)) LinkDisarmService.disarm(player);
         teleport(player, destinationLevel, position, target, instant);
-        if (properties.has(LinkProperties.MAINTAIN_MOMENTUM)) player.setDeltaMovement(momentum);
+        if (properties.has(LinkProperties.GENERATE_PLATFORM))
+            generateArrivalPlatform(destinationLevel, position);
+        applyMomentum(player, momentum, target, properties);
         player.resetFallDistance();
         return LinkResult.SUCCESS;
     }
 
+    /** Non-player portal travel follows the same link rules; Disarm may remove carried cargo. */
+    public static LinkResult travelEntityPortal(Entity entity, LinkTarget target,
+                                                LinkProperties properties, boolean requiresFooting) {
+        if (!(entity.level() instanceof ServerLevel source)) return LinkResult.MISSING_DIMENSION;
+        ServerLevel destinationLevel = source.getServer().getLevel(target.location().dimension());
+        if (destinationLevel == null) return LinkResult.MISSING_DIMENSION;
+        if (properties.has(LinkProperties.INTRA_LINKING_ONLY) && destinationLevel != source)
+            return LinkResult.INTRA_ONLY;
+        if (destinationLevel == source && !properties.has(LinkProperties.INTRA_LINKING)
+                && !properties.has(LinkProperties.INTRA_LINKING_ONLY)) return LinkResult.INTRA_LINKING_REQUIRED;
+        if (properties.has(LinkProperties.DISARM) && !LinkDisarmService.mayTravel(entity))
+            return LinkResult.DISARM_REJECTED;
+        if (!entity.canChangeDimensions(source, destinationLevel)) return LinkResult.NO_SAFE_DESTINATION;
+        BlockPos origin = landingOrigin(entity, destinationLevel, target, properties);
+        Optional<Vec3> destination = resolveDestination(destinationLevel, origin, requiresFooting);
+        if (destination.isEmpty()) return LinkResult.NO_SAFE_DESTINATION;
+
+        Vec3 momentum = entity.getDeltaMovement();
+        if (properties.has(LinkProperties.DISARM)) LinkDisarmService.disarm(entity);
+        Entity arrived = entity.changeDimension(new DimensionTransition(destinationLevel, destination.get(),
+                properties.has(LinkProperties.MAINTAIN_MOMENTUM)
+                        ? rotatedMomentum(momentum, target.yaw()) : Vec3.ZERO,
+                target.yaw(), target.pitch(), DimensionTransition.DO_NOTHING));
+        if (arrived == null) return LinkResult.NO_SAFE_DESTINATION;
+        if (!requiresFooting && properties.has(LinkProperties.GENERATE_PLATFORM))
+            generateArrivalPlatform(destinationLevel, destination.get());
+        arrived.setXRot(target.pitch());
+        arrived.resetFallDistance();
+        PortalTravelCooldown.mark(arrived, source.getServer().getTickCount());
+        return LinkResult.SUCCESS;
+    }
+
+    static Vec3 rotatedMomentum(Vec3 incoming, float destinationYaw) {
+        // Legacy rotates the horizontal speed to the destination yaw and adds a small upward lift.
+        double horizontalSpeed = Math.hypot(incoming.x, incoming.z);
+        double radians = Math.toRadians(destinationYaw);
+        return new Vec3(horizontalSpeed * Math.cos(radians), incoming.y + 0.2,
+                horizontalSpeed * Math.sin(radians));
+    }
+
+    private static void applyMomentum(ServerPlayer player, Vec3 incoming, LinkTarget target,
+                                      LinkProperties properties) {
+        player.setDeltaMovement(properties.has(LinkProperties.MAINTAIN_MOMENTUM)
+                ? rotatedMomentum(incoming, target.yaw()) : Vec3.ZERO);
+    }
+
+    private static void generateArrivalPlatform(ServerLevel level, Vec3 arrival) {
+        BlockPos feet = BlockPos.containing(arrival);
+        BlockPos floor = feet.below();
+        // Legacy only fills a missing floor when there is clear space above the arrival.
+        if (level.isEmptyBlock(floor) && level.isEmptyBlock(feet.above(2)))
+            level.setBlock(floor, ModBlocks.CLOUD_PLATFORM.get().defaultBlockState(), 3);
+    }
+
     /** Legacy relative links retain the traveller's offset from the source spawn. */
-    private static BlockPos landingOrigin(ServerPlayer player, ServerLevel destinationLevel,
+    private static BlockPos landingOrigin(Entity player, ServerLevel destinationLevel,
                                           LinkTarget target, LinkProperties properties) {
         if (!properties.has(LinkProperties.RELATIVE_LINK)) return target.location().pos();
-        BlockPos sourceSpawn = player.serverLevel().getSharedSpawnPos();
+        BlockPos sourceSpawn = ((ServerLevel) player.level()).getSharedSpawnPos();
         BlockPos destinationSpawn = destinationLevel.getSharedSpawnPos();
         BlockPos departure = player.blockPosition();
         return destinationSpawn.offset(departure.getX() - sourceSpawn.getX(),
                 departure.getY() - sourceSpawn.getY(), departure.getZ() - sourceSpawn.getZ());
     }
 
-    /** Drop each inventory stack as an item entity at the departure point. */
-    private static void dropInventoryAtSource(ServerPlayer player) {
-        var inventory = player.getInventory();
-        for (int slot = 0; slot < inventory.getContainerSize(); slot++) {
-            var stack = inventory.getItem(slot);
-            if (stack.isEmpty()) continue;
-            inventory.setItem(slot, net.minecraft.world.item.ItemStack.EMPTY);
-            player.drop(stack, false);
-        }
-        player.containerMenu.broadcastChanges();
-    }
-
     private static void teleport(
             ServerPlayer player,
             ServerLevel destinationLevel,
@@ -285,6 +333,7 @@ public final class LinkingService {
         MISSING_DIMENSION,
         INTRA_LINKING_REQUIRED,
         INTRA_ONLY,
+        DISARM_REJECTED,
         NO_SAFE_DESTINATION
     }
 }

src/main/java/net/dnorberg/rivencraft/client/screen/LinkModifierScreen.java

@@ -6,6 +6,7 @@ import net.dnorberg.rivencraft.menu.LinkModifierMenu;
 import net.dnorberg.rivencraft.network.SetLinkModifierTitlePayload;
 import net.dnorberg.rivencraft.network.SetLinkModifierSeedPayload;
 import net.dnorberg.rivencraft.registry.ModDataComponents;
+import net.dnorberg.rivencraft.registry.ModItems;
 import net.minecraft.client.gui.GuiGraphics;
 import net.minecraft.client.gui.components.EditBox;
 import net.minecraft.client.gui.components.Tooltip;
@@ -137,9 +138,12 @@ public final class LinkModifierScreen extends AbstractContainerScreen<LinkModifi
     @Override protected void renderBg(GuiGraphics graphics, float partialTick, int mouseX, int mouseY) {
         graphics.blit(BACKGROUND, leftPos, topPos, 0, 0, imageWidth, imageHeight, 256, 256);
         LinkProperties properties = menu.book().getOrDefault(ModDataComponents.LINK_PROPERTIES.get(), LinkProperties.NONE);
-        for (int index = 0; index < FLAGS.length; index++)
+        for (int index = 0; index < FLAGS.length; index++) {
+            boolean selected = FLAGS[index] == LinkProperties.DISABLE_PLATFORM
+                    ? platformEnabled(properties) : properties.has(FLAGS[index]);
             square(graphics, 5 + (index / 3) * 20, 10 + (index % 3) * 20,
-                    properties.has(FLAGS[index]), false);
+                    selected, false);
+        }
         if (menu.canDelete(minecraft.player)) {
             square(graphics, 120, 32, menu.awaitingDeletionConfirmation(), false);
             if (menu.awaitingDeletionConfirmation()) square(graphics, 140, 32, false, true);
@@ -166,8 +170,8 @@ public final class LinkModifierScreen extends AbstractContainerScreen<LinkModifi
                 if (inside(mouseX, mouseY, 5 + (index / 3) * 20, 10 + (index % 3) * 20, 18, 18)) {
                     Component label = FLAGS[index] == LinkProperties.DISABLE_PLATFORM
                             ? Component.literal("Generate Platform: "
-                            + (menu.book().getOrDefault(ModDataComponents.LINK_PROPERTIES.get(), LinkProperties.NONE)
-                            .has(LinkProperties.DISABLE_PLATFORM) ? "Off" : "On"))
+                            + (platformEnabled(menu.book().getOrDefault(ModDataComponents.LINK_PROPERTIES.get(),
+                            LinkProperties.NONE)) ? "On" : "Off"))
                             : LinkProperties.name(FLAGS[index]);
                     graphics.renderTooltip(font, label, mouseX, mouseY);
                     return;
@@ -180,4 +184,10 @@ public final class LinkModifierScreen extends AbstractContainerScreen<LinkModifi
                     ? "screen.rivencraft.link_modifier.confirm" : "screen.rivencraft.link_modifier.retire"),
                     mouseX, mouseY);
     }
+
+    private boolean platformEnabled(LinkProperties properties) {
+        return menu.book().is(ModItems.LINKING_BOOK.get())
+                ? properties.has(LinkProperties.GENERATE_PLATFORM)
+                : !properties.has(LinkProperties.DISABLE_PLATFORM);
+    }
 }

src/main/java/net/dnorberg/rivencraft/menu/LinkModifierMenu.java

@@ -142,7 +142,8 @@ public final class LinkModifierMenu extends AbstractContainerMenu {
             case TOGGLE_INTRA -> LinkProperties.INTRA_LINKING;
             case TOGGLE_INTRA_ONLY -> LinkProperties.INTRA_LINKING_ONLY;
             case TOGGLE_RELATIVE -> LinkProperties.RELATIVE_LINK;
-            case TOGGLE_PLATFORM -> LinkProperties.DISABLE_PLATFORM;
+            case TOGGLE_PLATFORM -> book().is(ModItems.LINKING_BOOK.get())
+                    ? LinkProperties.GENERATE_PLATFORM : LinkProperties.DISABLE_PLATFORM;
             default -> 0;
         };
         if (flag == 0 || ((flag == LinkProperties.INTRA_LINKING || flag == LinkProperties.INTRA_LINKING_ONLY)

src/main/java/net/dnorberg/rivencraft/mixin/MobDropChanceAccessor.java

@@ -0,0 +1,12 @@
+package net.dnorberg.rivencraft.mixin;
+
+import net.minecraft.world.entity.EquipmentSlot;
+import net.minecraft.world.entity.Mob;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Invoker;
+
+@Mixin(Mob.class)
+public interface MobDropChanceAccessor {
+    @Invoker("getEquipmentDropChance")
+    float rivencraft$getEquipmentDropChance(EquipmentSlot slot);
+}

src/main/java/net/dnorberg/rivencraft/portal/PortalTravelCooldown.java

@@ -2,12 +2,13 @@ package net.dnorberg.rivencraft.portal;
 
 import java.util.Map;
 import java.util.WeakHashMap;
+import net.minecraft.world.entity.Entity;
 import net.minecraft.server.level.ServerPlayer;
 
 /** Session-only portal cooldowns: tick counters must never be saved with players. */
 public final class PortalTravelCooldown {
     public static final long TICKS = 40;
-    private static final Map<ServerPlayer, Long> LAST_USE = new WeakHashMap<>();
+    private static final Map<Entity, Long> LAST_USE = new WeakHashMap<>();
 
     private PortalTravelCooldown() {}
 
@@ -15,16 +16,16 @@ public final class PortalTravelCooldown {
         return previous >= 0 && now >= previous && now - previous < TICKS;
     }
 
-    public static boolean blocked(ServerPlayer player, long now) {
-        return blocked(now, LAST_USE.getOrDefault(player, -1L));
+    public static boolean blocked(Entity entity, long now) {
+        return blocked(now, LAST_USE.getOrDefault(entity, -1L));
     }
 
-    public static void mark(ServerPlayer player, long now) {
-        LAST_USE.put(player, now);
+    public static void mark(Entity entity, long now) {
+        LAST_USE.put(entity, now);
     }
 
-    public static void forget(ServerPlayer player) {
-        LAST_USE.remove(player);
+    public static void forget(Entity entity) {
+        LAST_USE.remove(entity);
     }
 
     public static void clear() {

src/main/java/net/dnorberg/rivencraft/portal/PortalTravelQueue.java

@@ -7,34 +7,43 @@ import java.util.List;
 import java.util.Map;
 import net.dnorberg.rivencraft.block.entity.BookReceptacleBlockEntity;
 import net.dnorberg.rivencraft.block.entity.CrystalPortalBlockEntity;
+import net.dnorberg.rivencraft.book.AgeDimensionService;
+import net.dnorberg.rivencraft.book.AgeReference;
+import net.dnorberg.rivencraft.book.LinkDisarmService;
+import net.dnorberg.rivencraft.book.LinkProperties;
+import net.dnorberg.rivencraft.book.LinkTarget;
+import net.dnorberg.rivencraft.book.LinkingService;
 import net.dnorberg.rivencraft.item.DescriptiveBookItem;
 import net.dnorberg.rivencraft.item.LinkingBookItem;
+import net.dnorberg.rivencraft.registry.ModDataComponents;
 import net.dnorberg.rivencraft.registry.ModItems;
+import net.dnorberg.rivencraft.writing.OrderedWriting;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
 
 /** Defers block-collision travel until the movement packet that entered the portal has finished. */
 public final class PortalTravelQueue {
-    private static final Map<ServerPlayer, Pending> PENDING = new IdentityHashMap<>();
+    private static final Map<Entity, Pending> PENDING = new IdentityHashMap<>();
 
     private record Pending(ServerLevel source, BlockPos portal, BlockPos receptacle,
                            ItemStack book, long queuedTick) {}
-    private record Travel(ServerPlayer player, Pending pending) {}
+    private record Travel(Entity entity, Pending pending) {}
 
     private PortalTravelQueue() {}
 
-    public static void enqueue(ServerPlayer player, ServerLevel source, BlockPos portal,
+    public static void enqueue(Entity entity, ServerLevel source, BlockPos portal,
                                BlockPos receptacle, ItemStack book, long now) {
-        PENDING.putIfAbsent(player, new Pending(source, portal.immutable(), receptacle.immutable(),
+        PENDING.putIfAbsent(entity, new Pending(source, portal.immutable(), receptacle.immutable(),
                 book.copyWithCount(1), now));
     }
 
     public static void process(MinecraftServer server) {
         List<Travel> ready = new ArrayList<>();
-        Iterator<Map.Entry<ServerPlayer, Pending>> iterator = PENDING.entrySet().iterator();
+        Iterator<Map.Entry<Entity, Pending>> iterator = PENDING.entrySet().iterator();
         while (iterator.hasNext()) {
             var entry = iterator.next();
             if (server.getTickCount() <= entry.getValue().queuedTick()) continue;
@@ -44,21 +53,45 @@ public final class PortalTravelQueue {
         // Travel can itself cause block-collision callbacks, so do not keep an
         // iterator over the pending map while changing the player's dimension.
         for (Travel travel : ready) {
-            ServerPlayer player = travel.player();
+            Entity entity = travel.entity();
             Pending pending = travel.pending();
-            if (server.getPlayerList().getPlayer(player.getUUID()) != player
-                    || !player.isAlive() || player.serverLevel() != pending.source()
+            if ((entity instanceof ServerPlayer player
+                    && server.getPlayerList().getPlayer(player.getUUID()) != player)
+                    || entity.isRemoved() || !entity.isAlive() || entity.level() != pending.source()
                     || !(pending.source().getBlockEntity(pending.portal()) instanceof CrystalPortalBlockEntity portal)
                     || !pending.receptacle().equals(portal.receptacle())
                     || !(pending.source().getBlockEntity(pending.receptacle()) instanceof BookReceptacleBlockEntity holder)
                     || !ItemStack.isSameItemSameComponents(holder.getBook(), pending.book())) continue;
-            if (pending.book().is(ModItems.LINKING_BOOK.get()))
-                LinkingBookItem.usePortalBook(player, pending.book());
-            else if (pending.book().is(ModItems.DESCRIPTIVE_BOOK.get()))
-                DescriptiveBookItem.usePortalBook(player, pending.book());
+            if (entity instanceof ServerPlayer player) {
+                if (pending.book().is(ModItems.LINKING_BOOK.get()))
+                    LinkingBookItem.usePortalBook(player, pending.book());
+                else if (pending.book().is(ModItems.DESCRIPTIVE_BOOK.get()))
+                    DescriptiveBookItem.usePortalBook(player, pending.book());
+            } else {
+                travelEntity(entity, pending);
+            }
         }
     }
 
+    private static void travelEntity(Entity entity, Pending pending) {
+        ItemStack book = pending.book();
+        LinkProperties properties = book.getOrDefault(ModDataComponents.LINK_PROPERTIES.get(), LinkProperties.NONE);
+        if (properties.has(LinkProperties.DISARM) && !LinkDisarmService.mayTravel(entity)) return;
+        LinkTarget target;
+        boolean descriptive = book.is(ModItems.DESCRIPTIVE_BOOK.get());
+        if (descriptive) {
+            AgeReference reference = book.get(ModDataComponents.AGE_REFERENCE.get());
+            if (reference == null) return;
+            properties = properties.forDescriptiveBook();
+            target = AgeDimensionService.resolve(pending.source(), reference, OrderedWriting.EMPTY,
+                    !properties.has(LinkProperties.DISABLE_PLATFORM)).orElse(null);
+        } else if (book.is(ModItems.LINKING_BOOK.get())) {
+            target = book.get(ModDataComponents.LINK_TARGET.get());
+        } else return;
+        if (target == null) return;
+        LinkingService.travelEntityPortal(entity, target, properties, descriptive);
+    }
+
     public static void forget(ServerPlayer player) { PENDING.remove(player); }
     public static void clear() { PENDING.clear(); }
 }

src/main/resources/assets/rivencraft/lang/en_us.json

@@ -18,6 +18,7 @@
   "item.rivencraft.link_property.intra_linking_only": "Intra-Linking Only",
   "item.rivencraft.link_property.relative_link": "Relative Link",
   "item.rivencraft.link_property.disable_platform": "Generate Platform: Off",
+  "item.rivencraft.link_property.generate_platform": "Generate Platform: On",
   "item.rivencraft.page.unresolved": "Unresolved Symbol Page",
   "item.rivencraft.notebook": "Notebook",
   "item.rivencraft.collation_folder": "Collation Folder",

src/main/resources/rivencraft.mixins.json

@@ -7,6 +7,7 @@
     "AgeDimensionSeedMixin",
     "AgeDungeonPlacementMixin",
     "AgeStructureBiomeMixin",
+    "MobDropChanceAccessor",
     "StructurePlacementAccessor"
   ],
   "client": [