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- Experimental fix to disappearing entities when contraption seating reaches across chunk boundaries on save

src/main/java/com/simibubi/create/AllEntityTypes.java

@@ -26,7 +26,7 @@ public class AllEntityTypes {
 	public static final RegistryEntry<EntityType<SuperGlueEntity>> SUPER_GLUE =
 			register("super_glue", SuperGlueEntity::new, EntityClassification.MISC, 10, Integer.MAX_VALUE, false, SuperGlueEntity::build);
 	public static final RegistryEntry<EntityType<SeatEntity>> SEAT =
-			register("seat", SeatEntity::new, EntityClassification.MISC, 5, Integer.MAX_VALUE, false, SeatEntity::build);
+			register("seat", SeatEntity::new, EntityClassification.MISC, 0, Integer.MAX_VALUE, false, SeatEntity::build);
 
 	private static <T extends Entity> RegistryEntry<EntityType<T>> register(String name, IFactory<T> factory,
 			EntityClassification group, int range, int updateFrequency, boolean sendVelocity,

src/main/java/com/simibubi/create/content/contraptions/components/structureMovement/CancelPlayerFallPacket.java

@@ -1,36 +0,0 @@
-package com.simibubi.create.content.contraptions.components.structureMovement;
-
-import java.util.function.Supplier;
-
-import com.simibubi.create.foundation.networking.SimplePacketBase;
-
-import net.minecraft.entity.player.ServerPlayerEntity;
-import net.minecraft.network.PacketBuffer;
-import net.minecraftforge.fml.network.NetworkEvent.Context;
-
-public class CancelPlayerFallPacket extends SimplePacketBase {
-
-	public CancelPlayerFallPacket() {
-	}
-
-	public CancelPlayerFallPacket(PacketBuffer buffer) {
-	}
-
-	@Override
-	public void write(PacketBuffer buffer) {
-	}
-
-	@Override
-	public void handle(Supplier<Context> context) {
-		context.get().enqueueWork(() -> {
-			ServerPlayerEntity sender = context.get().getSender();
-			if (sender == null)
-				return;
-			sender.handleFallDamage(sender.fallDistance, 1.0F);
-			sender.fallDistance = 0;
-			sender.onGround = true;
-		});
-		context.get().setPacketHandled(true);
-	}
-
-}

src/main/java/com/simibubi/create/content/contraptions/components/structureMovement/ContraptionCollider.java

@@ -61,7 +61,6 @@ import net.minecraftforge.event.TickEvent.WorldTickEvent;
 import net.minecraftforge.event.entity.EntityJoinWorldEvent;
 import net.minecraftforge.event.entity.living.LivingEvent.LivingUpdateEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
-import net.minecraftforge.fml.DistExecutor;
 import net.minecraftforge.fml.common.Mod.EventBusSubscriber;
 
 @EventBusSubscriber
@@ -118,7 +117,7 @@ public class ContraptionCollider {
 		if (!data.contains("ContraptionDismountLocation"))
 			return;
 		Vec3d position = VecHelper.readNBT(data.getList("ContraptionDismountLocation", NBT.TAG_DOUBLE));
-		if (entityLiving.getRidingEntity() == null) 
+		if (entityLiving.getRidingEntity() == null)
 			entityLiving.setPositionAndUpdate(position.x, position.y, position.z);
 		data.remove("ContraptionDismountLocation");
 	}
@@ -156,7 +155,6 @@ public class ContraptionCollider {
 		double conRotY = contraptionRotation.y;
 		double conRotZ = contraptionRotation.z;
 		Vec3d conMotion = contraptionPosition.subtract(contraptionEntity.getPrevPositionVec());
-		Vec3d conAngularMotion = contraptionRotation.subtract(contraptionEntity.getPrevRotationVec());
 		Vec3d contraptionCentreOffset = contraptionEntity.stationary ? centerOfBlock : Vec3d.ZERO.add(0, 0.5, 0);
 		boolean axisAlignedCollision = contraptionRotation.equals(Vec3d.ZERO);
 		Matrix3d rotation = null;
@@ -287,19 +285,8 @@ public class ContraptionCollider {
 //				entity.handleFallDamage(entity.fallDistance, 1); tunnelling issue
 				entity.fallDistance = 0;
 				entity.onGround = true;
-				if (!serverPlayer) {
+				if (!serverPlayer)
-
+					contactPointMotion = contraptionEntity.getContactPointMotion(entityPosition);
-					Vec3d contactPoint = entityPosition.subtract(contraptionCentreOffset)
-						.subtract(contraptionPosition);
-					contactPoint =
-						VecHelper.rotate(contactPoint, conAngularMotion.x, conAngularMotion.y, conAngularMotion.z);
-					contactPoint = contactPoint.add(contraptionPosition)
-						.add(contraptionCentreOffset)
-						.add(conMotion);
-					contactPointMotion = contactPoint.subtract(entityPosition);
-
-					DistExecutor.runWhenOn(Dist.CLIENT, () -> () -> checkForClientPlayerCollision(entity));
-				}
 			}
 
 			if (hardCollision) {
@@ -379,13 +366,6 @@ public class ContraptionCollider {
 		return vec3d;
 	}
 
-	@OnlyIn(Dist.CLIENT)
-	private static void checkForClientPlayerCollision(Entity entity) {
-		if (entity != Minecraft.getInstance().player)
-			return;
-		wasClientPlayerGrounded = true;
-	}
-
 	public static void pushEntityOutOfShape(Entity entity, VoxelShape voxelShape, Vec3d positionOffset,
 		Vec3d shapeMotion) {
 		AxisAlignedBB entityBB = entity.getBoundingBox()

src/main/java/com/simibubi/create/content/contraptions/components/structureMovement/ContraptionEntity.java

@@ -171,6 +171,11 @@ public class ContraptionEntity extends Entity implements IEntityAdditionalSpawnD
 			new ContraptionSeatMappingPacket(getEntityId(), contraption.seatMapping));
 	}
 
+	@Override
+	public void remove() {
+		super.remove();
+	}
+
 	@Override
 	protected void removePassenger(Entity passenger) {
 		Vec3d transformedVector = getPassengerPosition(passenger);
@@ -219,24 +224,27 @@ public class ContraptionEntity extends Entity implements IEntityAdditionalSpawnD
 			return false;
 
 		// Eject potential existing passenger
+		Entity toDismount = null;
 		for (Entry<UUID, Integer> entry : contraption.seatMapping.entrySet()) {
 			if (entry.getValue() != indexOfSeat)
 				continue;
 			for (Entity entity : getPassengers()) {
-				if (!entry.getKey().equals(entity.getUniqueID()))
+				if (!entry.getKey()
+					.equals(entity.getUniqueID()))
 					continue;
 				if (entity instanceof PlayerEntity)
 					return false;
-				if (!world.isRemote) {
+				toDismount = entity;
-					Vec3d transformedVector = getPassengerPosition(entity);
-					entity.stopRiding();
-					if (transformedVector != null)
-						entity.setPositionAndUpdate(transformedVector.x, transformedVector.y, transformedVector.z);
-				}
-
 			}
 		}
 
+		if (toDismount != null && !world.isRemote) {
+			Vec3d transformedVector = getPassengerPosition(toDismount);
+			toDismount.stopRiding();
+			if (transformedVector != null)
+				toDismount.setPositionAndUpdate(transformedVector.x, transformedVector.y, transformedVector.z);
+		}
+
 		if (world.isRemote)
 			return true;
 		addSittingPassenger(player, indexOfSeat);
@@ -623,12 +631,32 @@ public class ContraptionEntity extends Entity implements IEntityAdditionalSpawnD
 			remove();
 			BlockPos offset = new BlockPos(getAnchorVec().add(.5, .5, .5));
 			Vec3d rotation = getRotationVec();
-			setBoundingBox(new AxisAlignedBB(0, 300, 0, 0, 300, 0));
 			contraption.addBlocksToWorld(world, offset, rotation, getPassengers());
+			removePassengers();
 //			preventMovedEntitiesFromGettingStuck();
 		}
 	}
 
+	@Override
+	public void onKillCommand() {
+		removePassengers();
+		super.onKillCommand();
+	}
+
+	@Override
+	protected void outOfWorld() {
+		removePassengers();
+		super.outOfWorld();
+	}
+
+	@Override
+	public void onRemovedFromWorld() {
+		super.onRemovedFromWorld();
+		if (world != null && world.isRemote)
+			return;
+		getPassengers().forEach(Entity::remove);
+	}
+
 	@Override
 	protected void doWaterSplashEffect() {}
 
@@ -684,6 +712,32 @@ public class ContraptionEntity extends Entity implements IEntityAdditionalSpawnD
 		}
 	}
 
+	@SuppressWarnings("deprecation")
+	@Override
+	public CompoundNBT writeWithoutTypeId(CompoundNBT nbt) {
+		Vec3d vec = getPositionVec();
+		List<Entity> passengers = getPassengers();
+		List<Vec3d> positionVecs = new ArrayList<>(passengers.size());
+
+		for (Entity entity : passengers) {
+			Vec3d prevVec = entity.getPositionVec();
+			positionVecs.add(prevVec);
+
+			// setPos has world accessing side-effects when removed == false
+			entity.removed = true;
+
+			// Gather passengers into same chunk when saving
+			entity.setPos(vec.x, prevVec.y, vec.z);
+
+			// Super requires all passengers to not be removed in order to write them to the
+			// tag
+			entity.removed = false;
+		}
+
+		CompoundNBT tag = super.writeWithoutTypeId(nbt);
+		return tag;
+	}
+
 	public Contraption getContraption() {
 		return contraption;
 	}
@@ -762,6 +816,20 @@ public class ContraptionEntity extends Entity implements IEntityAdditionalSpawnD
 		return new Vec3d(prevPosX, prevPosY, prevPosZ);
 	}
 
+	public Vec3d getContactPointMotion(Vec3d globalContactPoint) {
+		Vec3d positionVec = getPositionVec();
+		Vec3d conMotion = positionVec.subtract(getPrevPositionVec());
+		Vec3d conAngularMotion = getRotationVec().subtract(getPrevRotationVec());
+		Vec3d contraptionCentreOffset = stationary ? VecHelper.getCenterOf(BlockPos.ZERO) : Vec3d.ZERO.add(0, 0.5, 0);
+		Vec3d contactPoint = globalContactPoint.subtract(contraptionCentreOffset)
+			.subtract(positionVec);
+		contactPoint = VecHelper.rotate(contactPoint, conAngularMotion.x, conAngularMotion.y, conAngularMotion.z);
+		contactPoint = contactPoint.add(positionVec)
+			.add(contraptionCentreOffset)
+			.add(conMotion);
+		return contactPoint.subtract(globalContactPoint);
+	}
+
 	public boolean canCollideWith(Entity e) {
 		if (e instanceof PlayerEntity && e.isSpectator())
 			return false;

src/main/java/com/simibubi/create/content/contraptions/components/structureMovement/piston/LinearActuatorTileEntity.java

@@ -3,11 +3,8 @@ package com.simibubi.create.content.contraptions.components.structureMovement.pi
 import java.util.List;
 
 import com.simibubi.create.content.contraptions.base.KineticTileEntity;
-import com.simibubi.create.content.contraptions.components.structureMovement.CancelPlayerFallPacket;
-import com.simibubi.create.content.contraptions.components.structureMovement.ContraptionCollider;
 import com.simibubi.create.content.contraptions.components.structureMovement.ContraptionEntity;
 import com.simibubi.create.content.contraptions.components.structureMovement.IControlContraption;
-import com.simibubi.create.foundation.networking.AllPackets;
 import com.simibubi.create.foundation.tileEntity.TileEntityBehaviour;
 import com.simibubi.create.foundation.tileEntity.behaviour.ValueBoxTransform;
 import com.simibubi.create.foundation.tileEntity.behaviour.scrollvalue.ScrollOptionBehaviour;
@@ -42,7 +39,7 @@ public abstract class LinearActuatorTileEntity extends KineticTileEntity impleme
 	public void addBehaviours(List<TileEntityBehaviour> behaviours) {
 		super.addBehaviours(behaviours);
 		movementMode = new ScrollOptionBehaviour<>(MovementMode.class, Lang.translate("contraptions.movement_mode"),
-				this, getMovementModeSlot());
+			this, getMovementModeSlot());
 		movementMode.requiresWrench();
 		movementMode.withCallback(t -> waitingForSpeedChange = false);
 		behaviours.add(movementMode);
@@ -208,15 +205,7 @@ public abstract class LinearActuatorTileEntity extends KineticTileEntity impleme
 
 	protected abstract Vec3d toPosition(float offset);
 
-	protected void visitNewPosition() {
+	protected void visitNewPosition() {}
-		if (!world.isRemote)
-			return;
-		if (!ContraptionCollider.wasClientPlayerGrounded)
-			return;
-		// Send falldamage-cancel for the colliding player
-		ContraptionCollider.wasClientPlayerGrounded = false;
-		AllPackets.channel.sendToServer(new CancelPlayerFallPacket());
-	}
 
 	protected void tryDisassemble() {
 		if (removed) {

src/main/java/com/simibubi/create/foundation/networking/AllPackets.java

@@ -5,7 +5,6 @@ import java.util.function.Function;
 import java.util.function.Supplier;
 
 import com.simibubi.create.Create;
-import com.simibubi.create.content.contraptions.components.structureMovement.CancelPlayerFallPacket;
 import com.simibubi.create.content.contraptions.components.structureMovement.ContraptionInteractionPacket;
 import com.simibubi.create.content.contraptions.components.structureMovement.ContraptionSeatMappingPacket;
 import com.simibubi.create.content.contraptions.components.structureMovement.ContraptionStallPacket;
@@ -45,7 +44,6 @@ public enum AllPackets {
 	CONFIGURE_FILTER(FilterScreenPacket.class, FilterScreenPacket::new),
 	CONFIGURE_FILTERING_AMOUNT(FilteringCountUpdatePacket.class, FilteringCountUpdatePacket::new),
 	CONFIGURE_SCROLLABLE(ScrollValueUpdatePacket.class, ScrollValueUpdatePacket::new),
-	CANCEL_FALL(CancelPlayerFallPacket.class, CancelPlayerFallPacket::new),
 	EXTENDO_INTERACT(ExtendoGripInteractionPacket.class, ExtendoGripInteractionPacket::new),
 	CONTRAPTION_INTERACT(ContraptionInteractionPacket.class, ContraptionInteractionPacket::new),
 	PLACE_ARM(ArmPlacementPacket.class, ArmPlacementPacket::new),