spin implementation

Initial implementation for /spin

src/main/java/net/fill1890/fabsit/FabSit.java

@@ -4,6 +4,7 @@
 import net.fabricmc.fabric.api.command.v2.CommandRegistrationCallback;
 import net.fill1890.fabsit.command.LayCommand;
 import net.fill1890.fabsit.command.SitCommand;
+import net.fill1890.fabsit.command.SpinCommand;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -16,6 +17,7 @@ public class FabSit implements ModInitializer {
 	public void onInitialize() {
 		CommandRegistrationCallback.EVENT.register(SitCommand::register);
 		CommandRegistrationCallback.EVENT.register(LayCommand::register);
+		CommandRegistrationCallback.EVENT.register(SpinCommand::register);
 
 		LOGGER.info("FabSit finished loading");
 	}

src/main/java/net/fill1890/fabsit/command/SpinCommand.java

@@ -0,0 +1,71 @@
+package net.fill1890.fabsit.command;
+
+import com.mojang.brigadier.CommandDispatcher;
+import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import me.lucko.fabric.api.permissions.v0.Permissions;
+import net.fill1890.fabsit.entity.Pose;
+import net.fill1890.fabsit.entity.PoseManagerEntity;
+import net.minecraft.block.BlockState;
+import net.minecraft.command.CommandRegistryAccess;
+import net.minecraft.server.command.CommandManager;
+import net.minecraft.server.command.ServerCommandSource;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.text.Text;
+import net.minecraft.util.math.BlockPos;
+
+import static net.minecraft.server.command.CommandManager.literal;
+
+/**
+ * /spin command implementation
+ * <br>
+ * Requires <code>fabsit.commands.spin</code> permission node, granted to all players by default
+ * <br>
+ * Implementation details taken from <a href="https://github.com/Gecolay/GSit">GSit</a>
+ */
+public class SpinCommand {
+    public static void register(CommandDispatcher<ServerCommandSource> dispatcher, CommandRegistryAccess commandRegistryAccess, CommandManager.RegistrationEnvironment registrationEnvironment) {
+       dispatcher.register(literal("spin")
+               .requires(Permissions.require("fabsit.commands.spin", true))
+               .executes(SpinCommand::run));
+    }
+
+    public static int run(CommandContext<ServerCommandSource> context) {
+        final ServerCommandSource source = context.getSource();
+        ServerPlayerEntity player;
+
+        try {
+            player = source.getPlayerOrThrow();
+        } catch (CommandSyntaxException e) {
+            source.sendError(Text.of("You must be a player to run this command!"));
+            return -1;
+        }
+
+        // toggle sitting if the player was sat down
+        if(player.hasVehicle()) {
+            player.dismountVehicle();
+            player.teleport(player.getX(), player.getY() + 0.6, player.getZ());
+            return 1;
+        }
+
+        // get the block below to check it isn't air
+        BlockState standingBlock = player.getEntityWorld().getBlockState(new BlockPos(player.getPos()).down());
+        // check cancel conditions
+        if(
+                player.isFallFlying()
+                || player.isSleeping()
+                || player.isSwimming()
+                || player.isSpectator()
+                || standingBlock.isAir()
+        ) { return -1; }
+
+        // create a new pose manager for spinning and sit the player down
+        // (player is then invisible and an npc spins)
+        PoseManagerEntity chair = new PoseManagerEntity(player.getEntityWorld(), player.getPos(), Pose.SPINNING, player);
+        player.getEntityWorld().spawnEntity(chair);
+        player.startRiding(chair, true);
+
+        return 1;
+
+    }
+}

src/main/java/net/fill1890/fabsit/entity/Pose.java

@@ -2,5 +2,6 @@
 
 public enum Pose {
     SITTING,
-    LAYING;
+    LAYING,
+    SPINNING;
 }

src/main/java/net/fill1890/fabsit/entity/PoseManagerEntity.java

@@ -44,12 +44,13 @@ public PoseManagerEntity(World world, Vec3d pos, Pose pose, ServerPlayerEntity p
         this.setYaw(player.getYaw()); // TODO: test this properly
 
         // if the pose is more complex than sitting, create a posing npc
-        if(pose == Pose.LAYING) {
+        if(pose == Pose.LAYING || pose == Pose.SPINNING) {
             // copy player game profile with a random uuid
             GameProfile gameProfile = new GameProfile(UUID.randomUUID(), player.getEntityName());
             gameProfile.getProperties().putAll(player.getGameProfile().getProperties());
 
-            this.poser = new LayingEntity(player, gameProfile);
+            if(pose == Pose.LAYING) this.poser = new LayingEntity(player, gameProfile);
+            if(pose == Pose.SPINNING) this.poser = new SpinningEntity(player, gameProfile);
         }
 
         this.pose = pose;
@@ -60,7 +61,7 @@ protected void addPassenger(Entity passenger) {
         super.addPassenger(passenger);
 
         // if the pose is npc-based, hide the player when initiated
-        if(this.pose == Pose.LAYING) {
+        if(this.pose == Pose.LAYING || this.pose == Pose.SPINNING) {
             passenger.setInvisible(true);
 
             // update shoulder entities
@@ -80,7 +81,7 @@ protected void removePassenger(Entity passenger) {
         super.removePassenger(passenger);
 
         // if the pose was npc-based, show the player again when exited
-        if(this.pose == Pose.LAYING) {
+        if(this.pose == Pose.LAYING || this.pose == Pose.SPINNING) {
             passenger.setInvisible(false);
 
             // replace shoulder entities
@@ -92,7 +93,7 @@ protected void removePassenger(Entity passenger) {
     }
 
     public void animate(int id) {
-        if(this.pose == Pose.LAYING) {
+        if(this.pose == Pose.LAYING || this.pose == Pose.SPINNING) {
             poser.animate(id);
         }
     }
@@ -133,7 +134,7 @@ public void tick() {
         if(sittingBlock.isAir()) { kill(); }
 
         // if pose is npc-based, update players with npc info
-        if(this.pose == Pose.LAYING) {
+        if(this.pose == Pose.LAYING || this.pose == Pose.SPINNING) {
             poser.sendUpdates();
         }
 

src/main/java/net/fill1890/fabsit/entity/SpinningEntity.java

@@ -0,0 +1,38 @@
+package net.fill1890.fabsit.entity;
+
+import com.mojang.authlib.GameProfile;
+import net.minecraft.network.packet.s2c.play.EntityS2CPacket;
+import net.minecraft.network.packet.s2c.play.EntityTrackerUpdateS2CPacket;
+import net.minecraft.server.network.ServerPlayerEntity;
+
+import static net.fill1890.fabsit.mixin.LivingEntityAccessor.getLIVING_FLAGS;
+
+public class SpinningEntity extends PosingEntity {
+    // pivot the poser to face vertically
+    EntityS2CPacket pivotPacket;
+
+    public SpinningEntity(ServerPlayerEntity player, GameProfile gameProfile) {
+        super(player, gameProfile);
+
+        // set spinning state
+        this.getDataTracker().set(getLIVING_FLAGS(), (byte) 0x04);
+        // refresh data packet
+        this.trackerPoserPacket = new EntityTrackerUpdateS2CPacket(this.getId(), this.getDataTracker(), true);
+
+        this.pivotPacket = new EntityS2CPacket.RotateAndMoveRelative(this.getId(), (short) 0, (short) 0, (short) 0, (byte) 0, (byte) (-90.0f * 256.0f / 360.0f), true);
+    }
+
+    @Override
+    public void sendUpdates() {
+        super.sendUpdates();
+
+        // rotate the poser to be spinning vertically
+        this.addingPlayers.forEach(p -> p.networkHandler.sendPacket(this.pivotPacket));
+    }
+
+    @Override
+    protected void syncHeadYaw() {
+        // do nothing; no point since already rotating
+        // also might mess up angle
+    }
+}

src/main/java/net/fill1890/fabsit/mixin/LivingEntityAccessor.java

@@ -14,4 +14,7 @@ public interface LivingEntityAccessor {
     static TrackedData<Optional<BlockPos>> getSLEEPING_POSITION() {
         throw new AssertionError();
     }
+
+    @Accessor("LIVING_FLAGS")
+    static TrackedData<Byte> getLIVING_FLAGS() { throw new AssertionError(); }
 }