Super cool entities and fun

- Conductor entities now rotate to face their carts' motion
- Fixed Contraption passengers not visible to clients whenever the seat position offsets them out of ticking chunks just after loading in

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

@@ -28,6 +28,7 @@ import com.simibubi.create.content.contraptions.components.structureMovement.int
 import com.simibubi.create.content.contraptions.components.structureMovement.mounted.MountedContraption;
 import com.simibubi.create.content.contraptions.components.structureMovement.sync.ContraptionSeatMappingPacket;
 import com.simibubi.create.foundation.collision.Matrix3d;
+import com.simibubi.create.foundation.mixin.accessor.ServerLevelAccessor;
 import com.simibubi.create.foundation.networking.AllPackets;
 import com.simibubi.create.foundation.utility.AngleHelper;
 import com.simibubi.create.foundation.utility.VecHelper;
@@ -44,10 +45,13 @@ import net.minecraft.network.syncher.EntityDataAccessor;
 import net.minecraft.network.syncher.EntityDataSerializers;
 import net.minecraft.network.syncher.SynchedEntityData;
 import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.util.Mth;
 import net.minecraft.world.InteractionHand;
 import net.minecraft.world.damagesource.DamageSource;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.EntityType;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.entity.decoration.ArmorStand;
 import net.minecraft.world.entity.decoration.HangingEntity;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.entity.projectile.Projectile;
@@ -267,7 +271,7 @@ public abstract class AbstractContraptionEntity extends Entity implements IEntit
 	}
 
 	@Override
-	public final void tick() {
+	public void tick() {
 		if (contraption == null) {
 			discard();
 			return;
@@ -287,6 +291,40 @@ public abstract class AbstractContraptionEntity extends Entity implements IEntit
 		contraption.onEntityTick(level);
 		tickContraption();
 		super.tick();
+
+		if (!(level instanceof ServerLevelAccessor sl))
+			return;
+
+		for (Entity entity : getPassengers()) {
+			if (entity instanceof Player)
+				continue;
+			if (entity.isAlwaysTicking())
+				continue;
+			if (sl.create$getEntityTickList()
+				.contains(entity))
+				continue;
+			positionRider(entity);
+		}
+	}
+
+	public void alignPassenger(Entity passenger) {
+		Vec3 motion = getContactPointMotion(passenger.getEyePosition());
+		if (Mth.equal(motion.length(), 0))
+			return;
+		if (passenger instanceof ArmorStand)
+			return;
+		if (!(passenger instanceof LivingEntity living))
+			return;
+		float angle = AngleHelper.deg(-Mth.atan2(motion.x, motion.z));
+		if (level.isClientSide) {
+			living.lerpTo(0, 0, 0, 0, 0, 0, false);
+			living.lerpHeadTo(0, 0);
+			living.setYRot(angle);
+			living.setXRot(0);
+			living.yBodyRot = angle;
+			living.yHeadRot = angle;
+		} else
+			living.setYRot(angle);
 	}
 
 	protected abstract void tickContraption();
@@ -496,7 +534,7 @@ public abstract class AbstractContraptionEntity extends Entity implements IEntit
 			return;
 
 		StructureTransform transform = makeStructureTransform();
-		
+
 		contraption.stop(level);
 		AllPackets.channel.send(PacketDistributor.TRACKING_ENTITY.with(() -> this),
 			new ContraptionDisassemblyPacket(this.getId(), transform));
@@ -561,9 +599,6 @@ public abstract class AbstractContraptionEntity extends Entity implements IEntit
 	@Override
 	public void onRemovedFromWorld() {
 		super.onRemovedFromWorld();
-		if (level != null && level.isClientSide)
-			return;
-		getPassengers().forEach(Entity::discard);
 	}
 
 	@Override

src/main/java/com/simibubi/create/content/logistics/trains/entity/Carriage.java

@@ -20,6 +20,7 @@ import com.simibubi.create.foundation.utility.VecHelper;
 import net.minecraft.core.BlockPos;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.Tag;
+import net.minecraft.server.level.ServerLevel;
 import net.minecraft.util.Mth;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.Entity.RemovalReason;
@@ -160,18 +161,21 @@ public class Carriage {
 
 	public void createEntity(Level level) {
 		Entity entity = EntityType.loadEntityRecursive(serialisedEntity, level, e -> {
-			level.addFreshEntity(e);
+			e.moveTo(positionAnchor);
 			return e;
 		});
+
 		if (!(entity instanceof CarriageContraptionEntity cce))
 			return;
 
-		Vec3 pos = positionAnchor;
-		cce.setPos(pos);
-		cce.setCarriage(this);
 		cce.setGraph(train.graph == null ? null : train.graph.id);
+		cce.setCarriage(this);
 		cce.syncCarriage();
+
 		this.entity = new WeakReference<>(cce);
+
+		if (level instanceof ServerLevel sl)
+			sl.tryAddFreshEntityWithPassengers(entity);
 	}
 
 	public void manageEntity(Level level) {
@@ -196,11 +200,13 @@ public class Carriage {
 	}
 
 	private void removeAndSaveEntity(CarriageContraptionEntity entity) {
+		serialisedEntity = entity.serializeNBT();
+
 		for (Entity passenger : entity.getPassengers())
 			if (!(passenger instanceof Player))
-				passenger.remove(RemovalReason.UNLOADED_WITH_PLAYER);
+				passenger.discard();
-		serialisedEntity = entity.serializeNBT();
 		entity.discard();
+
 		this.entity.clear();
 	}
 

src/main/java/com/simibubi/create/content/logistics/trains/entity/CarriageContraptionEntity.java

@@ -124,9 +124,24 @@ public class CarriageContraptionEntity extends OrientedContraptionEntity {
 		return entity;
 	}
 
+	@Override
+	public void tick() {
+		super.tick();
+
+		if (contraption instanceof CarriageContraption cc)
+			for (Entity entity : getPassengers()) {
+				BlockPos seatOf = cc.getSeatOf(entity.getUUID());
+				if (seatOf == null)
+					continue;
+				if (cc.conductorSeats.get(seatOf) == null)
+					continue;
+				alignPassenger(entity);
+			}
+	}
+
 	@Override
 	protected void tickContraption() {
-		if (!(contraption instanceof CarriageContraption))
+		if (!(contraption instanceof CarriageContraption cc))
 			return;
 		if (carriage == null) {
 			if (level.isClientSide) {

src/main/java/com/simibubi/create/foundation/mixin/accessor/ServerLevelAccessor.java

@@ -0,0 +1,13 @@
+package com.simibubi.create.foundation.mixin.accessor;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Accessor;
+
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.entity.EntityTickList;
+
+@Mixin(ServerLevel.class)
+public interface ServerLevelAccessor {
+	@Accessor("entityTickList")
+	EntityTickList create$getEntityTickList();
+}

src/main/resources/create.mixins.json

@@ -9,6 +9,7 @@
     "accessor.AbstractProjectileDispenseBehaviorAccessor",
     "accessor.DispenserBlockAccessor",
     "accessor.FallingBlockEntityAccessor",
+    "accessor.ServerLevelAccessor",
     "accessor.LivingEntityAccessor"
   ],
   "client": [