Expose level+position in IPocketAccess

This allows pocket upgrades (modems and speakers) to read the position
directly, rather than checking whether the entity is present.

projects/common-api/src/main/java/dan200/computercraft/api/pocket/IPocketAccess.java

@@ -9,8 +9,10 @@
 import dan200.computercraft.api.upgrades.UpgradeData;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.phys.Vec3;
 import org.jetbrains.annotations.ApiStatus;
 
 import javax.annotation.Nullable;
@@ -21,6 +23,20 @@
  */
 @ApiStatus.NonExtendable
 public interface IPocketAccess {
+    /**
+     * Get the level in which the pocket computer exists.
+     *
+     * @return The pocket computer's level.
+     */
+    ServerLevel getLevel();
+
+    /**
+     * Get the position of the pocket computer.
+     *
+     * @return The pocket computer's position.
+     */
+    Vec3 getPosition();
+
     /**
      * Gets the entity holding this item.
      * <p>

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketBrain.java

@@ -16,8 +16,10 @@
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.phys.Vec3;
 
 import javax.annotation.Nullable;
 import java.util.Collections;
@@ -34,6 +36,7 @@ public final class PocketBrain implements IPocketAccess {
     private final PocketServerComputer computer;
 
     private PocketHolder holder;
+    private Vec3 position;
 
     private boolean dirty = false;
     private @Nullable UpgradeData<IPocketUpgrade> upgrade;
@@ -43,6 +46,7 @@ public final class PocketBrain implements IPocketAccess {
     public PocketBrain(PocketHolder holder, int computerID, @Nullable String label, ComputerFamily family, @Nullable UpgradeData<IPocketUpgrade> upgrade) {
         this.computer = new PocketServerComputer(this, holder, computerID, label, family);
         this.holder = holder;
+        this.position = holder.pos();
         this.upgrade = UpgradeData.copyOf(upgrade);
         invalidatePeripheral();
     }
@@ -66,6 +70,7 @@ PocketHolder holder() {
      * @param newHolder The new holder
      */
     public void updateHolder(PocketHolder newHolder) {
+        position = newHolder.pos();
         computer.setPosition(newHolder.level(), newHolder.blockPos());
 
         var oldHolder = this.holder;
@@ -94,6 +99,18 @@ public boolean updateItem(ItemStack stack) {
         return true;
     }
 
+    @Override
+    public ServerLevel getLevel() {
+        return computer.getLevel();
+    }
+
+    @Override
+    public Vec3 getPosition() {
+        // This method can be called from off-thread, and so we must use the cached position rather than rereading
+        // from the holder.
+        return position;
+    }
+
     @Override
     public @Nullable Entity getEntity() {
         return holder instanceof PocketHolder.EntityHolder entity && holder.isValid(computer) ? entity.entity() : null;

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketHolder.java

@@ -11,6 +11,7 @@
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.item.ItemEntity;
+import net.minecraft.world.phys.Vec3;
 
 /**
  * An object that holds a pocket computer item.
@@ -23,6 +24,13 @@ public sealed interface PocketHolder permits PocketHolder.EntityHolder {
      */
     ServerLevel level();
 
+    /**
+     * The position of this holder.
+     *
+     * @return The position of this holder.
+     */
+    Vec3 pos();
+
     /**
      * The block position of this holder.
      *
@@ -59,6 +67,11 @@ default ServerLevel level() {
             return (ServerLevel) entity().level();
         }
 
+        @Override
+        default Vec3 pos() {
+            return entity().getEyePosition();
+        }
+
         @Override
         default BlockPos blockPos() {
             return entity().blockPosition();

projects/common/src/main/java/dan200/computercraft/shared/pocket/peripherals/PocketModem.java

@@ -31,8 +31,6 @@ public IPeripheral createPeripheral(IPocketAccess access) {
     public void update(IPocketAccess access, @Nullable IPeripheral peripheral) {
         if (!(peripheral instanceof PocketModemPeripheral modem)) return;
 
-        modem.setLocation(access);
-
         var state = modem.getModemState();
         if (state.pollChanged()) access.setLight(state.isOpen() ? 0xBA0000 : -1);
     }

projects/common/src/main/java/dan200/computercraft/shared/pocket/peripherals/PocketModemPeripheral.java

@@ -14,31 +14,21 @@
 import javax.annotation.Nullable;
 
 public class PocketModemPeripheral extends WirelessModemPeripheral {
-    private @Nullable Level level = null;
-    private Vec3 position = Vec3.ZERO;
+    private final IPocketAccess access;
 
     public PocketModemPeripheral(boolean advanced, IPocketAccess access) {
         super(new ModemState(), advanced);
-        setLocation(access);
-    }
-
-    void setLocation(IPocketAccess access) {
-        var entity = access.getEntity();
-        if (entity != null) {
-            level = entity.level();
-            position = entity.getEyePosition(1);
-        }
+        this.access = access;
     }
 
     @Override
     public Level getLevel() {
-        if (level == null) throw new IllegalStateException("Using modem before position has been defined");
-        return level;
+        return access.getLevel();
     }
 
     @Override
     public Vec3 getPosition() {
-        return position;
+        return access.getPosition();
     }
 
     @Override

projects/common/src/main/java/dan200/computercraft/shared/pocket/peripherals/PocketSpeakerPeripheral.java

@@ -8,15 +8,11 @@
 import dan200.computercraft.api.pocket.IPocketAccess;
 import dan200.computercraft.shared.peripheral.speaker.SpeakerPosition;
 import dan200.computercraft.shared.peripheral.speaker.UpgradeSpeakerPeripheral;
-import net.minecraft.world.level.Level;
-import net.minecraft.world.phys.Vec3;
 
 import javax.annotation.Nullable;
 
 public class PocketSpeakerPeripheral extends UpgradeSpeakerPeripheral {
     private final IPocketAccess access;
-    private @Nullable Level level;
-    private Vec3 position = Vec3.ZERO;
 
     public PocketSpeakerPeripheral(IPocketAccess access) {
         this.access = access;
@@ -25,7 +21,7 @@ public PocketSpeakerPeripheral(IPocketAccess access) {
     @Override
     public SpeakerPosition getPosition() {
         var entity = access.getEntity();
-        return entity == null ? SpeakerPosition.of(level, position) : SpeakerPosition.of(entity);
+        return entity == null ? SpeakerPosition.of(access.getLevel(), access.getPosition()) : SpeakerPosition.of(entity);
     }
 
     @Override
@@ -35,12 +31,6 @@ public boolean equals(@Nullable IPeripheral other) {
 
     @Override
     public void update() {
-        var entity = access.getEntity();
-        if (entity != null) {
-            level = entity.level();
-            position = entity.position();
-        }
-
         super.update();
 
         access.setLight(madeSound() ? 0x3320fc : -1);