More stuff for stations. Cleanup.

src/main/java/net/xevianlight/aphelion/block/custom/LaunchPad.java

@@ -2,8 +2,12 @@ package net.xevianlight.aphelion.block.custom;
 
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.context.BlockPlaceContext;
+import net.minecraft.world.level.Level;
 import net.minecraft.world.level.LevelAccessor;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.SoundType;
@@ -11,7 +15,12 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.block.state.StateDefinition;
 import net.minecraft.world.level.block.state.properties.BlockStateProperties;
 import net.minecraft.world.level.block.state.properties.BooleanProperty;
+import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.core.init.ModDimensions;
+import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
+import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
 import net.xevianlight.aphelion.util.ModTags;
+import net.xevianlight.aphelion.util.SpacePartition;
 import org.jetbrains.annotations.NotNull;
 
 public class LaunchPad extends Block {
@@ -73,5 +82,4 @@ public class LaunchPad extends Block {
         }
         return state;
     }
-
 }

src/main/java/net/xevianlight/aphelion/block/custom/RocketAssembler.java

@@ -2,6 +2,7 @@ package net.xevianlight.aphelion.block.custom;
 
 import com.mojang.serialization.MapCodec;
 import net.minecraft.core.BlockPos;
+import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.InteractionResult;
 import net.minecraft.world.entity.player.Player;
@@ -15,6 +16,9 @@ import net.minecraft.world.level.block.state.properties.BooleanProperty;
 import net.minecraft.world.phys.BlockHitResult;
 import net.xevianlight.aphelion.block.custom.base.BasicHorizontalEntityBlock;
 import net.xevianlight.aphelion.block.entity.custom.RocketAssemblerBlockEntity;
+import net.xevianlight.aphelion.core.init.ModDimensions;
+import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
+import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
 import net.xevianlight.aphelion.entites.vehicles.RocketEntity;
 import net.xevianlight.aphelion.util.AphelionBlockStateProperties;
 import org.jetbrains.annotations.NotNull;

src/main/java/net/xevianlight/aphelion/block/custom/base/BasicEntityBlock.java

@@ -37,14 +37,16 @@ public abstract class BasicEntityBlock extends BaseEntityBlock {
     public @Nullable <T extends BlockEntity> BlockEntityTicker<T> getTicker(@NotNull Level level, @NotNull BlockState state, @NotNull BlockEntityType<T> blockEntityType) {
         return !shouldTick ? null : (entityLevel, pos, blockState, blockEntity) -> {
             if (blockEntity instanceof TickableBlockEntity tickable) {
-                long time = level.getGameTime() - pos.hashCode();
+                if (!tickable.isInitialized()) tickable.firstTick(entityLevel, blockState, pos);
+
+                long time = entityLevel.getGameTime() - pos.hashCode();
                 tickable.tick(entityLevel, time, blockState, pos);
-                if (level.isClientSide()) {
+
-                    tickable.clientTick((ClientLevel) level, time, state, pos);
+                if (entityLevel.isClientSide()) {
+                    tickable.clientTick((ClientLevel) entityLevel, time, blockState, pos);
                 } else {
-                    tickable.serverTick((ServerLevel) level, time, state, pos);
+                    tickable.serverTick((ServerLevel) entityLevel, time, blockState, pos);
                 }
-                if (!tickable.isInitialized()) tickable.firstTick(level, state, pos);
             }
         };
     }

src/main/java/net/xevianlight/aphelion/block/custom/base/StationEngineBlockEntity.java

@@ -0,0 +1,77 @@
+package net.xevianlight.aphelion.block.custom.base;
+
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.core.BlockPos;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.entity.BlockEntityType;
+import net.minecraft.world.level.block.state.BlockState;
+import net.xevianlight.aphelion.core.init.ModDimensions;
+import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
+import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
+
+import javax.annotation.Nullable;
+
+public abstract class StationEngineBlockEntity extends BlockEntity implements TickableBlockEntity {
+
+    private boolean isInitialized = false;
+    private @Nullable PartitionData data;
+
+    /**
+     * The travel speed in AU/tick.
+     */
+    public abstract double getTravelSpeed();
+
+    protected StationEngineBlockEntity(BlockEntityType<?> type, BlockPos pos, BlockState blockState) {
+        super(type, pos, blockState);
+    }
+
+    @Override
+    public void clientTick(ClientLevel level, long time, BlockState state, BlockPos pos) {
+
+    }
+
+    /**
+     * Handles station travel logic for this engine.
+     *
+     * <p>If the associated station is currently traveling, this method advances
+     * its movement using the value returned by {@link #getTravelSpeed()}.</p>
+     *
+     * <p>Subclasses may override this method to add additional server-side behavior.
+     * When doing so, {@code super.serverTick(...)} should be called to preserve
+     * the default travel logic.</p>
+     *
+     * <p>This method is invoked once per server tick.</p>
+     *
+     * @param level the server level the block entity exists in
+     * @param time the current tick time offset used for scheduling
+     * @param state the current block state
+     * @param pos the world position of the block entity
+     */
+    @Override
+    public void serverTick(ServerLevel level, long time, BlockState state, BlockPos pos) {
+        double speed = getTravelSpeed();
+        if (data != null) {
+            if (data.isTraveling()) {
+                data.travel(speed);
+            }
+        }
+    }
+
+    @Override
+    public boolean isInitialized() {
+        return isInitialized;
+    }
+
+    @Override
+    public void firstTick(Level level, BlockState state, BlockPos pos) {
+        if (level.isClientSide()) return;
+        if (level instanceof ServerLevel serverLevel) {
+            if (serverLevel.dimension() == ModDimensions.SPACE) {
+                data = SpacePartitionSavedData.get(serverLevel).getDataForBlockPos(pos);
+            }
+        }
+        isInitialized = true;
+    }
+}

src/main/java/net/xevianlight/aphelion/block/custom/base/StationRocketEngineBlockEntity.java

@@ -0,0 +1,32 @@
+package net.xevianlight.aphelion.block.custom.base;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntityType;
+import net.minecraft.world.level.block.state.BlockState;
+import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
+import net.xevianlight.aphelion.util.Constants;
+
+public class StationRocketEngineBlockEntity extends StationEngineBlockEntity {
+
+    /// Seconds to travel 1 AU
+    private final double SECONDS_PER_AU = 60;
+    /// AU per tick
+    private final double SPEED = 1/(SECONDS_PER_AU*20);
+
+    @Override
+    public double getTravelSpeed() {
+        return SPEED;
+    }
+
+    protected StationRocketEngineBlockEntity(BlockEntityType<?> type, BlockPos pos, BlockState blockState) {
+        // TODO change type to ModBlockEntities.STATION_ROCKET_ENGINE_BLOCK_ENTITY.get()
+        super(type, pos, blockState);
+    }
+
+    @Override
+    public void serverTick(ServerLevel level, long time, BlockState state, BlockPos pos) {
+        super.serverTick(level, time, state, pos); // IMPORTANT!!!
+    }
+}

src/main/java/net/xevianlight/aphelion/block/custom/base/TickableBlockEntity.java

@@ -9,41 +9,74 @@ import net.minecraft.world.level.block.state.BlockState;
 public interface TickableBlockEntity {
 
     /**
-     * Runs on both the client AND server.
+     * Runs on both the client and server once per tick.
-     * @param level
+     *
-     * @param time
+     * <p>This is intended for logic that is common to both sides. Side-specific logic
-     * @param state
+     * should go in {@link #clientTick(ClientLevel, long, BlockState, BlockPos)} or
-     * @param pos
+     * {@link #serverTick(ServerLevel, long, BlockState, BlockPos)}.</p>
+     *
+     * @param level the current level
+     * @param time a deterministic per-position tick time (see ticker implementation)
+     * @param state the current block state
+     * @param pos the world position of the block entity
      */
     default void tick (Level level, long time, BlockState state, BlockPos pos) {};
 
     /**
-     * Runs on the client only
+     * Runs on the client only once per tick.
-     * @param level
+     *
-     * @param time
+     * <p>Use this for client-side visual updates, particles, sounds, animation state,
-     * @param state
+     * or other logic that must not run on the logical server.</p>
-     * @param pos
+     *
+     * @param level the client level
+     * @param time a deterministic per-position tick time (see ticker implementation)
+     * @param state the current block state
+     * @param pos the world position of the block entity
      */
     void clientTick(ClientLevel level, long time, BlockState state, BlockPos pos);
 
     /**
-     * Runs on the server only
+     * Runs on the server only once per tick.
-     * @param level
+     *
-     * @param time
+     * <p>Use this for authoritative game logic such as inventory processing, energy
-     * @param state
+     * generation/consumption, entity spawning, saving state, and network sync triggers.</p>
-     * @param pos
+     *
+     * @param level the server level
+     * @param time a deterministic per-position tick time (see ticker implementation)
+     * @param state the current block state
+     * @param pos the world position of the block entity
      */
     void serverTick(ServerLevel level, long time, BlockState state, BlockPos pos);
 
+    /**
+     * Returns whether this object has completed its initialization logic.
+     *
+     * <p>If this method returns {@code false}, {@link #firstTick(Level, BlockState, BlockPos)}
+     * will be invoked at the start of each tick on both the client and server until
+     * initialization is complete.</p>
+     *
+     * <p>Implementations should return {@code true} once initialization has finished
+     * to prevent {@code firstTick} from running again.</p>
+     *
+     * @return {@code true} if initialization has completed, {@code false} otherwise
+     */
     default boolean isInitialized() {
         return true;
-    };
+    }
 
     /**
-     * Runs on client AND server, once only.
+     * Performs initialization logic for this object.
-     * @param level
+     *
-     * @param state
+     * <p>This method is called at the start of each tick on both the client and server
-     * @param pos
+     * whenever {@link #isInitialized()} returns {@code false}. It will continue to be
+     * invoked every tick until initialization is complete.</p>
+     *
+     * <p>Implementations should perform any required setup and ensure that
+     * {@code isInitialized()} returns {@code true} afterward.</p>
+     *
+     * @param level the level the block entity exists in
+     * @param state the current block state
+     * @param pos the world position of the block entity
      */
     void firstTick(Level level, BlockState state, BlockPos pos);
 

src/main/java/net/xevianlight/aphelion/block/entity/custom/RocketAssemblerBlockEntity.java

@@ -21,6 +21,9 @@ import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.block.custom.base.TickableBlockEntity;
 import net.xevianlight.aphelion.core.init.ModBlockEntities;
 import net.xevianlight.aphelion.core.init.ModBlocks;
+import net.xevianlight.aphelion.core.init.ModDimensions;
+import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
+import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
 import net.xevianlight.aphelion.entites.vehicles.RocketEntity;
 import net.xevianlight.aphelion.util.AphelionBlockStateProperties;
 import net.xevianlight.aphelion.util.ModTags;
@@ -38,6 +41,8 @@ public class RocketAssemblerBlockEntity extends BlockEntity implements TickableB
     private PadInfo padBounds;
     RocketEntity lastRocket;
 
+    private @Nullable PartitionData data;
+
     public @Nullable PadInfo getPadBounds() {
         return padBounds;
     }
@@ -60,9 +65,19 @@ public class RocketAssemblerBlockEntity extends BlockEntity implements TickableB
 
             return dx * dy * dz;
         }
+
+        public BlockPos getCenter() {
+            int centerX = (min.getX() + max.getX()) / 2;
+            int centerZ = (min.getZ() + max.getZ()) / 2;
+
+            // bottom Y level
+            int y = min.getY();
+
+            return new BlockPos(centerX, y, centerZ);
+        }
     }
 
-    private final Block TOWER_BLOCK = ModBlocks.BLOCK_STEEL.get();
+    private static final Block TOWER_BLOCK = ModBlocks.BLOCK_STEEL.get();
     public BlockPos towerBasePos;
 
     private boolean connected(BlockState state, Direction dir) {
@@ -318,23 +333,44 @@ public class RocketAssemblerBlockEntity extends BlockEntity implements TickableB
         boolean formed = newBounds != null;
         if (state.getValue(AphelionBlockStateProperties.FORMED) != formed) {
             level.setBlockAndUpdate(pos, state.setValue(AphelionBlockStateProperties.FORMED, formed));
+            if (data != null) {
+                if (formed) {
+                    data.addLandingPadController(pos);
+                } else {
+                    data.removeLandingPadController(pos);
+                }
+            }
         }
     }
 
     @Override
     public void firstTick(Level level, BlockState state, BlockPos pos) {
+        if (level.isClientSide()) return;
+
         facing = getBlockState().getValue(BlockStateProperties.HORIZONTAL_FACING);
         padScanStart = getBlockPos().mutable().below().relative(facing.getOpposite());
+
+        if (level instanceof ServerLevel serverLevel) {
+            if (serverLevel.dimension() == ModDimensions.SPACE) {
+                data = SpacePartitionSavedData.get(serverLevel).getDataForBlockPos(pos);
+            }
+        }
+
         this.isInitialized = true;
     }
 
+    @Override
+    public void onRemoved() {
+        if (data == null) return;
+        data.removeLandingPadController(worldPosition);
+    }
 
     private static boolean isPad(BlockState s) {
         return s.is(ModTags.Blocks.LAUNCH_PAD); // or s.getBlock() == ModBlocks.PAD.get()
     }
 
     private static boolean isTower(BlockState s) {
-        return s.is(ModBlocks.BLOCK_STEEL);
+        return s.is(TOWER_BLOCK);
     }
 
     @Override

src/main/java/net/xevianlight/aphelion/block/entity/custom/renderer/RocketAssemblerBlockEntityRenderer.java

@@ -1,14 +1,18 @@
 package net.xevianlight.aphelion.block.entity.custom.renderer;
 
+import com.mojang.blaze3d.vertex.DefaultVertexFormat;
 import com.mojang.blaze3d.vertex.PoseStack;
 import com.mojang.blaze3d.vertex.VertexConsumer;
+import com.mojang.blaze3d.vertex.VertexFormat;
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.LevelRenderer;
 import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.RenderStateShard;
 import net.minecraft.client.renderer.RenderType;
 import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
 import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
 import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
 import net.minecraft.world.phys.AABB;
 import net.xevianlight.aphelion.block.entity.custom.RocketAssemblerBlockEntity;
 import org.jetbrains.annotations.NotNull;
@@ -37,6 +41,21 @@ public class RocketAssemblerBlockEntityRenderer implements BlockEntityRenderer<R
         ).inflate(0.5);
     }
 
+    private static final RenderType CENTER_FACE = RenderType.create(
+            "aphelion_center_face",
+            DefaultVertexFormat.POSITION_COLOR,
+            VertexFormat.Mode.QUADS,
+            256,
+            false,
+            true,
+            RenderType.CompositeState.builder()
+                    .setShaderState(RenderStateShard.POSITION_COLOR_SHADER)
+                    .setTransparencyState(RenderStateShard.TRANSLUCENT_TRANSPARENCY)
+                    .setCullState(RenderStateShard.NO_CULL)
+                    .setDepthTestState(RenderStateShard.LEQUAL_DEPTH_TEST)
+                    .createCompositeState(false)
+    );
+
     @Override
     public void render(@NotNull RocketAssemblerBlockEntity be, float v, @NotNull PoseStack poseStack, @NotNull MultiBufferSource multiBufferSource, int i, int i1) {
 //        if (!Minecraft.getInstance().gui.getDebugOverlay().showDebugScreen()) return;
@@ -53,10 +72,20 @@ public class RocketAssemblerBlockEntityRenderer implements BlockEntityRenderer<R
         poseStack.pushPose();
         poseStack.translate(-be.getBlockPos().getX(), -be.getBlockPos().getY(), -be.getBlockPos().getZ());
 
-        VertexConsumer vc = multiBufferSource.getBuffer(RenderType.lines());
+        VertexConsumer lineVc = multiBufferSource.getBuffer(RenderType.lines());
+        LevelRenderer.renderLineBox(poseStack, lineVc, box, 0f, 1f, 0f, 1f);
 
-        LevelRenderer.renderLineBox(poseStack, vc, box, 0.0f, 1.0f, 0.0f, 1.0f);
+        VertexConsumer faceVc = multiBufferSource.getBuffer(CENTER_FACE);
 
+        BlockPos center = be.getPadBounds().getCenter();
+        float y = center.getY() + 0.01f; // avoid z-fighting
+
+        LevelRenderer.renderFace(
+                poseStack, faceVc, Direction.UP,
+                center.getX(), y, center.getZ(),
+                center.getX() + 1, y, center.getZ() + 1,
+                1f, 0f, 0f, 0.5f
+        );
         poseStack.popPose();
     }
 }

src/main/java/net/xevianlight/aphelion/client/AphelionDebugOverlay.java

@@ -3,7 +3,6 @@ package net.xevianlight.aphelion.client;
 import net.minecraft.client.Minecraft;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.level.ServerLevel;
-import net.minecraft.world.level.Level;
 import net.minecraft.world.level.dimension.DimensionType;
 import net.neoforged.bus.api.SubscribeEvent;
 import net.neoforged.fml.common.EventBusSubscriber;
@@ -15,7 +14,7 @@ import net.xevianlight.aphelion.client.dimension.DimensionRendererCache;
 import net.xevianlight.aphelion.client.dimension.SpaceSkyEffects;
 import net.xevianlight.aphelion.core.saveddata.EnvironmentSavedData;
 import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
-import net.xevianlight.aphelion.util.SpacePartitionHelper;
+import net.xevianlight.aphelion.util.SpacePartition;
 
 @EventBusSubscriber(modid = Aphelion.MOD_ID, value = Dist.CLIENT)
 public class AphelionDebugOverlay {
@@ -44,8 +43,8 @@ public class AphelionDebugOverlay {
                 + ", thickFog=" + r.hasThickFog()
                 + ", fog=" + r.hasFog());
 
-        int x = SpacePartitionHelper.get(Math.floor(mc.player.position().x));
+        int x = SpacePartition.get(Math.floor(mc.player.position().x));
-        int z = SpacePartitionHelper.get(Math.floor(mc.player.position().z));
+        int z = SpacePartition.get(Math.floor(mc.player.position().z));
 
         // Left side of F3
         event.getLeft().add("");

src/main/java/net/xevianlight/aphelion/client/dimension/DimensionSkyEffects.java

@@ -8,7 +8,7 @@ import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.phys.Vec3;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.client.PartitionClientState;
-import net.xevianlight.aphelion.util.SpacePartitionHelper;
+import net.xevianlight.aphelion.util.SpacePartition;
 import org.jetbrains.annotations.Nullable;
 import org.joml.Matrix4f;
 
@@ -61,8 +61,8 @@ public class DimensionSkyEffects extends DimensionSpecialEffects {
 
     public static ResourceLocation orbitForPos(Vec3 pos) {
 
-        int x = SpacePartitionHelper.get(pos.x);
+        int x = SpacePartition.get(pos.x);
-        int z = SpacePartitionHelper.get(pos.z);
+        int z = SpacePartition.get(pos.z);
 
         Minecraft mc = Minecraft.getInstance();
         if (mc.level == null) return ResourceLocation.fromNamespaceAndPath(Aphelion.MOD_ID, "orbit/default");

src/main/java/net/xevianlight/aphelion/client/dimension/SpaceSkyEffects.java

@@ -8,7 +8,7 @@ import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.phys.Vec3;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.client.PartitionClientState;
-import net.xevianlight.aphelion.util.SpacePartitionHelper;
+import net.xevianlight.aphelion.util.SpacePartition;
 import org.jetbrains.annotations.Nullable;
 import org.joml.Matrix4f;
 
@@ -67,8 +67,8 @@ public class SpaceSkyEffects extends DimensionSpecialEffects {
 
     public static ResourceLocation orbitForPos(Vec3 pos) {
 
-        int x = SpacePartitionHelper.get(pos.x);
+        int x = SpacePartition.get(pos.x);
-        int z = SpacePartitionHelper.get(pos.z);
+        int z = SpacePartition.get(pos.z);
 
         Minecraft mc = Minecraft.getInstance();
         if (mc.level == null) return ResourceLocation.fromNamespaceAndPath(Aphelion.MOD_ID, "orbit/default");

src/main/java/net/xevianlight/aphelion/commands/AphelionCommand.java

@@ -11,7 +11,6 @@ import net.minecraft.commands.arguments.*;
 import net.minecraft.commands.arguments.coordinates.BlockPosArgument;
 import net.minecraft.commands.arguments.coordinates.ColumnPosArgument;
 import net.minecraft.core.BlockPos;
-import net.minecraft.core.UUIDUtil;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.network.chat.*;
@@ -26,10 +25,8 @@ import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
 import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
 import net.xevianlight.aphelion.entites.vehicles.RocketEntity;
-import net.xevianlight.aphelion.planet.Planet;
 import net.xevianlight.aphelion.util.RocketStructure;
-import net.xevianlight.aphelion.util.SpacePartitionHelper;
+import net.xevianlight.aphelion.util.SpacePartition;
-import net.xevianlight.aphelion.util.registries.ModRegistries;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Collection;
@@ -47,8 +44,8 @@ public class AphelionCommand {
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .then(Commands.argument("orbit", ResourceLocationArgument.id())
                                                         .executes(context -> {
-                                                            int x = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                            int x = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                            int z = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                            int z = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
                                                             ResourceLocation orbit = ResourceLocationArgument.getId(context, "orbit");
 
                                                             ServerLevel level = context.getSource().getLevel();
@@ -85,8 +82,8 @@ public class AphelionCommand {
                                 .then(Commands.literal("get")
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .executes(context -> {
-                                                    int x = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                    int x = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                    int z = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                    int z = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
 
                                                     ServerLevel level = context.getSource().getLevel();
                                                     ResourceLocation orbit = SpacePartitionSavedData.get(level).getOrbitForPartition(x, z);
@@ -110,8 +107,8 @@ public class AphelionCommand {
                                 .then(Commands.literal("clear")
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .executes(context -> {
-                                                    int x = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                    int x = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                    int z = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                    int z = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
 
                                                     ServerLevel level = context.getSource().getLevel();
 
@@ -148,8 +145,8 @@ public class AphelionCommand {
                                                         .executes(context -> {
                                                             ServerLevel level = context.getSource().getLevel();
 
-                                                            int x = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context,"pos").x());
+                                                            int x = SpacePartition.get(ColumnPosArgument.getColumnPos(context,"pos").x());
-                                                            int z = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context,"pos").z());
+                                                            int z = SpacePartition.get(ColumnPosArgument.getColumnPos(context,"pos").z());
 
                                                             long key = SpacePartitionSavedData.pack(x,z);
 
@@ -195,7 +192,7 @@ public class AphelionCommand {
                                                             int x = ColumnPosArgument.getColumnPos(context, "pos").x();
                                                             int z = ColumnPosArgument.getColumnPos(context, "pos").z();
 
-                                                            String stationCoord = SpacePartitionHelper.get(x) + " " + SpacePartitionHelper.get(z);
+                                                            String stationCoord = SpacePartition.get(x) + " " + SpacePartition.get(z);
 
                                                             Component clickableOutput = getClickablePos(stationCoord, ChatFormatting.GREEN);
 
@@ -217,8 +214,8 @@ public class AphelionCommand {
                                                     double x = (double) IntegerArgumentType.getInteger(context, "x");
                                                     double z = (double) IntegerArgumentType.getInteger(context, "z");
 
-                                                    int destX = (int) Math.floor(x * SpacePartitionHelper.SIZE) + (SpacePartitionHelper.SIZE / 2);
+                                                    int destX = (int) Math.floor(x * SpacePartition.SIZE) + (SpacePartition.SIZE / 2);
-                                                    int destZ = (int) Math.floor(z * SpacePartitionHelper.SIZE) + (SpacePartitionHelper.SIZE / 2);
+                                                    int destZ = (int) Math.floor(z * SpacePartition.SIZE) + (SpacePartition.SIZE / 2);
 
                                                     String stationCoord = x + ", " + z;
 
@@ -255,8 +252,8 @@ public class AphelionCommand {
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .then(Commands.argument("id", ResourceLocationArgument.id())
                                                         .executes(context -> {
-                                                            int px = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                            int px = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                            int pz = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                            int pz = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
                                                             ResourceLocation orbit = ResourceLocationArgument.getId(context, "id");
 
                                                             ServerLevel level = context.getSource().getLevel();
@@ -277,8 +274,8 @@ public class AphelionCommand {
                                 .then(Commands.literal("get")
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .executes(context -> {
-                                                    int px = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                    int px = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                    int pz = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                    int pz = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
 
                                                     ServerLevel level = context.getSource().getLevel();
                                                     PartitionData data = SpacePartitionSavedData.get(level).getData(px, pz);
@@ -306,8 +303,8 @@ public class AphelionCommand {
                                         .then(Commands.argument("pos", ColumnPosArgument.columnPos())
                                                 .then(Commands.argument("player", GameProfileArgument.gameProfile())
                                                         .executes(context -> {
-                                                            int px = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").x());
+                                                            int px = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").x());
-                                                            int pz = SpacePartitionHelper.get(ColumnPosArgument.getColumnPos(context, "pos").z());
+                                                            int pz = SpacePartition.get(ColumnPosArgument.getColumnPos(context, "pos").z());
 
                                                             ServerLevel level = context.getSource().getLevel();
                                                             PartitionData data = SpacePartitionSavedData.get(level).getData(px, pz);

src/main/java/net/xevianlight/aphelion/core/init/ModDimensions.java

@@ -0,0 +1,10 @@
+package net.xevianlight.aphelion.core.init;
+
+import net.minecraft.core.registries.Registries;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.world.level.Level;
+import net.xevianlight.aphelion.Aphelion;
+
+public final class ModDimensions {
+    public static final ResourceKey<Level> SPACE = ResourceKey.create(Registries.DIMENSION, Aphelion.id("space"));
+}

src/main/java/net/xevianlight/aphelion/core/saveddata/SpacePartitionSavedData.java

@@ -2,6 +2,7 @@ package net.xevianlight.aphelion.core.saveddata;
 
 import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
 import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+import net.minecraft.core.BlockPos;
 import net.minecraft.core.HolderLookup;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.ListTag;
@@ -10,6 +11,7 @@ import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.level.saveddata.SavedData;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
+import net.xevianlight.aphelion.util.SpacePartition;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -54,10 +56,10 @@ public class SpacePartitionSavedData extends SavedData {
 
             // Distances (optional; default 0.0)
             if (e.contains("DistanceTraveled", CompoundTag.TAG_DOUBLE)) {
-                pd.setDistanceTraveled(e.getDouble("DistanceTraveled"));
+                pd.setDistanceTraveledAU(e.getDouble("DistanceTraveled"));
             }
             if (e.contains("DistanceToDest", CompoundTag.TAG_DOUBLE)) {
-                pd.setDistanceToDest(e.getDouble("DistanceToDest"));
+                pd.setTripDistanceAU(e.getDouble("DistanceToDest"));
             }
 
             if (e.hasUUID("Owner")) {
@@ -102,8 +104,8 @@ public class SpacePartitionSavedData extends SavedData {
             // Traveling + distances
             e.putBoolean("Traveling", pd.isTraveling());
 
-            e.putDouble("DistanceTraveled", pd.getDistanceTraveled());
+            e.putDouble("DistanceTraveled", pd.getDistanceTraveledAU());
-            e.putDouble("DistanceToDest", pd.getDistanceToDest());
+            e.putDouble("DistanceToDest", pd.getTripDistanceAU());
 
             if (pd.getOwner() != null) {
                 e.putUUID("Owner", pd.getOwner());
@@ -158,15 +160,23 @@ public class SpacePartitionSavedData extends SavedData {
     }
 
     /**
-     * Gets the mutable PartitionData object stored at px, pz
+     * Returns the {@link PartitionData} stored at the given partition indices.
-     * @param px
+     *
-     * @param pz
+     * <p>The returned {@code PartitionData} is mutable. Any modifications to the returned
-     * @return
+     * object will be persisted to the server.</p>
+     *
+     * <p>If no {@code PartitionData} exists at the specified indices, a new instance is
+     * created using {@code aphelion:orbit/default}, stored in the server cache, and returned.</p>
+     *
+     * @param px the partition X index
+     * @param pz the partition Z index
+     * @return the {@code PartitionData} associated with the specified partition indices
      */
-    public @Nullable PartitionData getData(int px, int pz) {
+    public @NotNull PartitionData getData(int px, int pz) {
         long key = pack(px, pz);
         PartitionData data = map.get(key);
         if (data == null) {
+
             // pick a sensible default orbit, or null if you truly allow it
             data = new PartitionData(Aphelion.id("orbit/default"));
             map.put(key, data);
@@ -175,6 +185,61 @@ public class SpacePartitionSavedData extends SavedData {
         return data;
     }
 
+    /**
+     * Returns the {@link PartitionData} for the partition containing the given world position.
+     *
+     * <p>The returned {@code PartitionData} is mutable. Any modifications to the returned
+     * object will be persisted to the server.</p>
+     *
+     * <p>If no {@code PartitionData} exists for the partition containing the specified
+     * position, a new instance is created using {@code aphelion:orbit/default},
+     * stored in the server cache, and returned.</p>
+     *
+     * @param x the world X coordinate
+     * @param z the world Z coordinate
+     * @return the {@code PartitionData} associated with the partition containing the position
+     */
+    public @NotNull PartitionData getDataForPos(int x, int z) {
+        int px = SpacePartition.get(x);
+        int pz = SpacePartition.get(z);
+        long key = pack(px, pz);
+        PartitionData data = map.get(key);
+        if (data == null) {
+
+            data = new PartitionData(Aphelion.id("orbit/default"));
+            map.put(key, data);
+            setDirty();
+        }
+        return data;
+    }
+
+    /**
+     * Returns the {@link PartitionData} for the partition containing the given block position.
+     *
+     * <p>The returned {@code PartitionData} is mutable. Any modifications to the returned
+     * object will be persisted to the server.</p>
+     *
+     * <p>If no {@code PartitionData} exists for the partition containing the specified
+     * position, a new instance is created using {@code aphelion:orbit/default},
+     * stored in the server cache, and returned.</p>
+     *
+     * @param pos the world block position
+     * @return the {@code PartitionData} associated with the partition containing the position
+     */
+    public @NotNull PartitionData getDataForBlockPos(BlockPos pos) {
+        int px = SpacePartition.get(pos.getX());
+        int pz = SpacePartition.get(pos.getZ());
+        long key = pack(px, pz);
+        PartitionData data = map.get(key);
+        if (data == null) {
+
+            data = new PartitionData(Aphelion.id("orbit/default"));
+            map.put(key, data);
+            setDirty();
+        }
+        return data;
+    }
+
     public void overwriteAllExistingOrbits(ResourceLocation orbit) {
         if (map.isEmpty()) return;
 

src/main/java/net/xevianlight/aphelion/core/saveddata/types/PartitionData.java

@@ -3,17 +3,13 @@ package net.xevianlight.aphelion.core.saveddata.types;
 import io.netty.buffer.ByteBuf;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.UUIDUtil;
-import net.minecraft.nbt.CompoundTag;
 import net.minecraft.network.codec.ByteBufCodecs;
 import net.minecraft.network.codec.StreamCodec;
 import net.minecraft.resources.ResourceLocation;
 import net.xevianlight.aphelion.util.BigCodec;
 import org.jetbrains.annotations.Nullable;
 
-import java.util.List;
+import java.util.*;
-import java.util.Objects;
-import java.util.Optional;
-import java.util.UUID;
 
 public class PartitionData {
     public static final int MAX_PADS = 64;
@@ -22,32 +18,37 @@ public class PartitionData {
     @Nullable private ResourceLocation orbit;
     @Nullable private ResourceLocation destination;
     private boolean traveling;
-    private double distanceTraveled;
+    /// How far we've already gone
-    private double distanceToDest;
+    private double distanceTraveledAU;
+    /// Total trip distance, from start to finish
+    private double tripDistanceAU;
     private boolean generated;
     private UUID owner;
     private List<BlockPos> landingPadControllers;
+    private List<BlockPos> engines;
 
     public PartitionData(@Nullable ResourceLocation orbit) {
         this.orbit = orbit;
         this.destination = null;
         this.traveling = false;
-        this.distanceTraveled = 0;
+        this.distanceTraveledAU = 0;
-        this.distanceToDest = 0;
+        this.tripDistanceAU = 0;
         this.generated = false;
         this.owner = null;
         this.landingPadControllers = List.of();
+        this.engines = List.of();
     }
 
     public PartitionData(PartitionData other) {
         this.orbit = other.orbit;
         this.destination = other.destination;
         this.traveling = other.traveling;
-        this.distanceTraveled = other.distanceTraveled;
+        this.distanceTraveledAU = other.distanceTraveledAU;
-        this.distanceToDest = other.distanceToDest;
+        this.tripDistanceAU = other.tripDistanceAU;
         this.generated = other.generated;
         this.owner = other.owner;
         this.landingPadControllers = other.landingPadControllers;
+        this.engines = other.engines;
     }
 
     public static final StreamCodec<ByteBuf, PartitionData> STREAM_CODEC =
@@ -64,10 +65,10 @@ public class PartitionData {
 
                     // doubles -> DOUBLE codec
                     ByteBufCodecs.DOUBLE,
-                    PartitionData::getDistanceTraveled,
+                    PartitionData::getDistanceTraveledAU,
 
                     ByteBufCodecs.DOUBLE,
-                    PartitionData::getDistanceToDest,
+                    PartitionData::getTripDistanceAU,
 
                     ByteBufCodecs.optional(UUIDUtil.STREAM_CODEC),
                     d -> Optional.ofNullable(d.getOwner()),
@@ -78,15 +79,19 @@ public class PartitionData {
                     BLOCKPOS_LIST_CODEC,
                     PartitionData::getLandingPadControllers,
 
-                    (orbitOpt, destOpt, traveling, distTraveled, distToDest, ownerOpt, generated, controllers) -> {
+                    BLOCKPOS_LIST_CODEC,
+                    PartitionData::getEngines,
+
+                    (orbitOpt, destOpt, traveling, distTraveled, distToDest, ownerOpt, generated, controllers, engines) -> {
                         PartitionData data = new PartitionData(orbitOpt.orElse(null));
                         data.destination = destOpt.orElse(null);
                         data.traveling = traveling;
-                        data.distanceTraveled = distTraveled;
+                        data.distanceTraveledAU = distTraveled;
-                        data.distanceToDest = distToDest;
+                        data.tripDistanceAU = distToDest;
                         data.owner = ownerOpt.orElse(null);
                         data.generated = generated;
                         data.landingPadControllers = controllers;
+                        data.engines = engines;
                         return data;
                     }
             );
@@ -115,24 +120,35 @@ public class PartitionData {
         this.traveling = traveling;
     }
 
-    public double getDistanceTraveled() {
+    public double getDistanceTraveledAU() {
-        return distanceTraveled;
+        return distanceTraveledAU;
     }
 
-    public void setDistanceTraveled(double distanceTraveled) {
+    public void setDistanceTraveledAU(double distanceTraveledAU) {
-        this.distanceTraveled = distanceTraveled;
+        this.distanceTraveledAU = distanceTraveledAU;
     }
 
-    public double getDistanceToDest() {
+    public double getTripDistanceAU() {
-        return distanceToDest;
+        return tripDistanceAU;
     }
 
-    public void setDistanceToDest(double distanceToDest) {
+    public void setTripDistanceAU(double tripDistanceAU) {
-        this.distanceToDest = distanceToDest;
+        this.tripDistanceAU = tripDistanceAU;
     }
 
+    /**
+     * Advances travel progress by the specified distance in AU.
+     *
+     * <p>This increases {@code distanceTraveledAU} by the given amount and clamps
+     * the result so it never exceeds {@code tripDistanceAU}.</p>
+     *
+     * <p>If the requested distance would overshoot the destination, the traveled
+     * distance is set to exactly {@code tripDistanceAU}.</p>
+     *
+     * @param distance the distance to advance in astronomical units (AU)
+     */
     public void travel(double distance) {
-        distanceTraveled = Math.min( distanceTraveled + distance, distanceToDest);
+        distanceTraveledAU = Math.min(distanceTraveledAU + distance, tripDistanceAU);
     }
 
     public boolean isGenerated() {
@@ -151,14 +167,40 @@ public class PartitionData {
         this.owner = owner;
     }
 
+    /**
+     * Returns a copy of the world positions of all landing pad controllers tracked
+     * by this partition.
+     *
+     * <p>This method returns only the stored {@link BlockPos} locations of known
+     * landing pad controllers, not the controller instances or block entities
+     * themselves. To interact with a controller, retrieve its block entity from
+     * the world using the returned positions.</p>
+     *
+     * <p>The returned list is a defensive copy and may be modified without affecting
+     * the underlying partition data. To persist changes, use
+     * {@code setLandingPadControllers(...)}.</p>
+     *
+     * @return a mutable copy of the landing pad controller positions known to this partition
+     */
     public List<BlockPos> getLandingPadControllers() {
-        return landingPadControllers;
+        return new ArrayList<>(landingPadControllers);
     }
 
     public void setLandingPadControllers(List<BlockPos> landingPadControllers) {
         this.landingPadControllers = landingPadControllers;
     }
 
+
+    /**
+     * Adds a landing pad controller at the specified world position.
+     *
+     * <p>If a controller does not already exist at the given position, it is added
+     * to the internal collection and the method returns {@code true}. If a controller
+     * is already present at that position, no changes are made.</p>
+     *
+     * @param pos the world position of the landing pad controller to add
+     * @return {@code true} if the controller was added, {@code false} if it already existed
+     */
     public boolean addLandingPadController(BlockPos pos) {
         if (!landingPadControllers.contains(pos)) {
             landingPadControllers.add(pos);
@@ -167,10 +209,40 @@ public class PartitionData {
         return false;
     }
 
+    /**
+     * Removes the landing pad controller at the specified world position.
+     *
+     * <p>If a controller exists at the given position, it is removed from the
+     * internal collection and the method returns {@code true}. If no controller
+     * is present at that position, no changes are made.</p>
+     *
+     * @param pos the world position of the landing pad controller to remove
+     * @return {@code true} if a controller was removed, {@code false} otherwise
+     */
     public boolean removeLandingPadController(BlockPos pos) {
         return landingPadControllers.remove(pos);
     }
 
+    public List<BlockPos> getEngines() {
+        return engines;
+    }
+
+    public void setEngines(List<BlockPos> engines) {
+        this.engines = engines;
+    }
+
+    public boolean addEngine(BlockPos pos) {
+        if (!engines.contains(pos)) {
+            engines.add(pos);
+            return true;
+        }
+        return false;
+    }
+
+    public boolean removeEngine(BlockPos pos) {
+        return engines.remove(pos);
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (this == obj) return true;
@@ -181,8 +253,8 @@ public class PartitionData {
         return Objects.equals(this.orbit, that.orbit)
                 && Objects.equals(this.destination, that.destination)
                 && this.traveling == that.traveling
-                && Double.compare(this.distanceTraveled, that.distanceTraveled) == 0
+                && Double.compare(this.distanceTraveledAU, that.distanceTraveledAU) == 0
-                && Double.compare(this.distanceToDest, that.distanceToDest) == 0
+                && Double.compare(this.tripDistanceAU, that.tripDistanceAU) == 0
                 && this.generated == that.generated
                 && Objects.equals(this.owner, that.owner);
     }

src/main/java/net/xevianlight/aphelion/network/PartitionSync.java

@@ -10,7 +10,7 @@ import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.core.saveddata.SpacePartitionSavedData;
 import net.xevianlight.aphelion.core.saveddata.types.PartitionData;
 import net.xevianlight.aphelion.network.packet.PartitionPayload;
-import net.xevianlight.aphelion.util.SpacePartitionHelper;
+import net.xevianlight.aphelion.util.SpacePartition;
 
 import java.util.UUID;
 
@@ -42,8 +42,8 @@ public final class PartitionSync {
     }
 
     private static PartitionPayload computePartitionFor(ServerPlayer sp) {
-        int px = (int)Math.floor(sp.getX() / SpacePartitionHelper.SIZE);
+        int px = (int)Math.floor(sp.getX() / SpacePartition.SIZE);
-        int pz = (int)Math.floor(sp.getZ() / SpacePartitionHelper.SIZE);
+        int pz = (int)Math.floor(sp.getZ() / SpacePartition.SIZE);
 
         PartitionData live = SpacePartitionSavedData.get(sp.serverLevel()).getData(px, pz);
 

src/main/java/net/xevianlight/aphelion/util/SpacePartition.java

@@ -1,6 +1,6 @@
 package net.xevianlight.aphelion.util;
 
-public class SpacePartitionHelper {
+public class SpacePartition {
 
     public static final int SIZE = 16;