changed mixins to affect ALL entities (might cause bugs) and fixed fall damage

src/generated/resources/.cache/59eb3dbb5f86130e09b3c62d89b9525ee01cf52d

@@ -1,11 +1,12 @@
-// 1.21.1	2026-01-28T08:47:15.3186366	Loot Tables
-// 1.21.1	2026-01-26T19:04:46.4976369	Loot Tables
+// 1.21.1	2026-02-06T10:36:07.5023829	Loot Tables
 69d8318ddba171526d1fabb87d9d93548ed8598e data/aphelion/loot_table/blocks/arc_furnace_casing.json
 05f08985e601d30116f67e2f07b48b03b40cdca6 data/aphelion/loot_table/blocks/block_steel.json
 ff43a9c3741faf10b1e156a7a74d5cfb035cc118 data/aphelion/loot_table/blocks/dimension_changer.json
 b63130d9c10485676303d729807b6fcaac080294 data/aphelion/loot_table/blocks/electric_arc_furnace.json
-afb6519a03415b8e0d5bafc9fadb70905a398046 data/aphelion/loot_table/blocks/oxygen_test_block.json
+086c97543700ccc2f815da4e6c29f11159766889 data/aphelion/loot_table/blocks/gravity_test_block.json
 b9cfe672ead8e2673a7b2f5c4cec831e7e8e7040 data/aphelion/loot_table/blocks/launch_pad.json
+afb6519a03415b8e0d5bafc9fadb70905a398046 data/aphelion/loot_table/blocks/oxygen_test_block.json
+2c6748b2cfb5b78e0cc95a2f3583d4e50cb4c964 data/aphelion/loot_table/blocks/rocket_assemblerblock.json
 1ab50c99e9f478840b9d003fd56ebdcab12fbbce data/aphelion/loot_table/blocks/test_block.json
 7d8eeb99a1bc942a6e2cf292b21fd4534062b5ab data/aphelion/loot_table/blocks/vacuum_arc_furnace_controller.json
 797bf9839d79e08b4832c9eaf3cb303b0471ed0c data/aphelion/loot_table/blocks/vaf_dummy_block.json

src/generated/resources/.cache/a8139181fab9cfd94e67697230cbaca839a05e1f

@@ -1,19 +1,21 @@
-// 1.21.1	2026-01-28T08:47:15.3176368	Block States: aphelion
-// 1.21.1	2026-01-26T20:40:43.8251623	Block States: aphelion
+// 1.21.1	2026-02-06T10:36:07.5013847	Block States: aphelion
 851ff42f7b21dec86107c8e0cefb3934ae4ebc08 assets/aphelion/blockstates/block_steel.json
 30b9c0efd7aaadb5412d98e4568f98b3632adbb9 assets/aphelion/blockstates/dimension_changer.json
 cb4287104006c80c8396b290ab5258df65d62cef assets/aphelion/blockstates/electric_arc_furnace.json
+1975ab6c73f76642f8b6cfed00e0739b4ea5775f assets/aphelion/blockstates/gravity_test_block.json
 28131a570d3666b7f323de4ad8a69e52ceec92e2 assets/aphelion/blockstates/oxygen_test_block.json
 b86c50fddcf6c8c6c19cb748529239d5962a3ede assets/aphelion/blockstates/test_block.json
 a810b97f4dace35d026f28d96cb9c47c93600d75 assets/aphelion/models/block/block_steel.json
 2d3592b7ab7132908709243e97540151e0fb762e assets/aphelion/models/block/dimension_changer.json
 5f7e8674070f31a63875b5d6147153bfa0eef61a assets/aphelion/models/block/electric_arc_furnace.json
+ad49034f318c6bc14a4844cf598c6999296aa8a0 assets/aphelion/models/block/gravity_test_block.json
 746f23f150a01524ad03cbd1eb822bfbb7cf453b assets/aphelion/models/block/oxygen_test_block.json
 e0971228b4a1c4bc9dbab58a7dacdc3ae6037e02 assets/aphelion/models/block/test_block.json
 cdc831b0f1c462be64825fd34bd446e5b95afac6 assets/aphelion/models/item/arc_furnace_casing.json
 3599f9037eb2f66de1765318b97ab564c3eae92f assets/aphelion/models/item/block_steel.json
 db0ec473a016ce05c258cde18a217d47a9ea8324 assets/aphelion/models/item/dimension_changer.json
 279080c06ada87f54fd0a7b885b256dbe25a946a assets/aphelion/models/item/electric_arc_furnace.json
+8de1f7597e1fa82c5603a88040ad935aa1cb9b29 assets/aphelion/models/item/gravity_test_block.json
 24cf60e70f7d9450b0e70cf017662e80971bae17 assets/aphelion/models/item/oxygen_test_block.json
 74418ef1cf678e72e7534924274688ef5a68af0e assets/aphelion/models/item/test_block.json
 88ca3602517e99f7feaed57eddfc96965a25761c assets/aphelion/models/item/vacuum_arc_furnace_controller.json

src/generated/resources/assets/aphelion/blockstates/gravity_test_block.json

@@ -0,0 +1,7 @@
+{
+  "variants": {
+    "": {
+      "model": "aphelion:block/gravity_test_block"
+    }
+  }
+}

src/generated/resources/assets/aphelion/models/block/gravity_test_block.json

@@ -0,0 +1,6 @@
+{
+  "parent": "minecraft:block/cube_all",
+  "textures": {
+    "all": "aphelion:block/gravity_test_block"
+  }
+}

src/generated/resources/assets/aphelion/models/item/gravity_test_block.json

@@ -0,0 +1,3 @@
+{
+  "parent": "aphelion:block/gravity_test_block"
+}

src/generated/resources/data/aphelion/loot_table/blocks/gravity_test_block.json

@@ -0,0 +1,21 @@
+{
+  "type": "minecraft:block",
+  "pools": [
+    {
+      "bonus_rolls": 0.0,
+      "conditions": [
+        {
+          "condition": "minecraft:survives_explosion"
+        }
+      ],
+      "entries": [
+        {
+          "type": "minecraft:item",
+          "name": "aphelion:gravity_test_block"
+        }
+      ],
+      "rolls": 1.0
+    }
+  ],
+  "random_sequence": "aphelion:blocks/gravity_test_block"
+}

src/generated/resources/data/aphelion/loot_table/blocks/rocket_assemblerblock.json

@@ -0,0 +1,21 @@
+{
+  "type": "minecraft:block",
+  "pools": [
+    {
+      "bonus_rolls": 0.0,
+      "conditions": [
+        {
+          "condition": "minecraft:survives_explosion"
+        }
+      ],
+      "entries": [
+        {
+          "type": "minecraft:item",
+          "name": "minecraft:air"
+        }
+      ],
+      "rolls": 1.0
+    }
+  ],
+  "random_sequence": "aphelion:blocks/rocket_assemblerblock"
+}

src/main/java/net/xevianlight/aphelion/Aphelion.java

@@ -24,10 +24,7 @@ import net.xevianlight.aphelion.fluid.BaseFluidType;
 import net.xevianlight.aphelion.fluid.ModFluidTypes;
 import net.xevianlight.aphelion.fluid.ModFluids;
 import net.xevianlight.aphelion.recipe.ModRecipes;
-import net.xevianlight.aphelion.screen.ElectricArcFurnaceScreen;
-import net.xevianlight.aphelion.screen.ModMenuTypes;
-import net.xevianlight.aphelion.screen.TestBlockScreen;
-import net.xevianlight.aphelion.screen.VacuumArcFurnaceScreen;
+import net.xevianlight.aphelion.screen.*;
 import org.slf4j.Logger;
 import net.xevianlight.aphelion.entites.vehicles.RocketRenderer;
 
@@ -147,6 +144,7 @@ public class Aphelion {
             event.register(ModMenuTypes.TEST_BLOCK_MENU.get(), TestBlockScreen::new);
             event.register(ModMenuTypes.ELECTRIC_ARC_FURNACE_MENU.get(), ElectricArcFurnaceScreen::new);
             event.register(ModMenuTypes.VACUUM_ARC_FURNACE_MENU.get(), VacuumArcFurnaceScreen::new);
+            event.register(ModMenuTypes.GRAVITY_TEST_BLOCK_MENU.get(), GravityTestBlockScreen::new);
         }
 
         @SubscribeEvent

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

@@ -0,0 +1,57 @@
+package net.xevianlight.aphelion.block.custom;
+
+import com.mojang.serialization.MapCodec;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.network.chat.Component;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.InteractionResult;
+import net.minecraft.world.SimpleMenuProvider;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.BaseEntityBlock;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.phys.BlockHitResult;
+import net.xevianlight.aphelion.block.custom.base.BasicEntityBlock;
+import net.xevianlight.aphelion.block.entity.custom.GravityTestBlockEntity;
+import net.xevianlight.aphelion.block.entity.custom.OxygenTestBlockEntity;
+import net.xevianlight.aphelion.block.entity.custom.TestBlockEntity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class GravityTestBlock extends BasicEntityBlock {
+
+    public GravityTestBlock(Properties properties) {super(properties, true);}
+
+    @Override
+    protected MapCodec<? extends BaseEntityBlock> codec() {return null;}
+
+    @Override
+    public @Nullable BlockEntity newBlockEntity(BlockPos blockPos, BlockState blockState) {
+        return new GravityTestBlockEntity(blockPos, blockState);
+    }
+
+    public static Properties getProperties() {return Properties.of();}
+
+    @Override
+    protected void onRemove(BlockState state, @NotNull Level level, @NotNull BlockPos pos, BlockState newState, boolean movedByPiston) {
+        if (state.getBlock() != newState.getBlock()) {
+            BlockEntity blockEntity = level.getBlockEntity(pos);
+            if (blockEntity instanceof GravityTestBlockEntity BE) {
+                BE.removeGravityArea();
+            }
+        }
+        super.onRemove(state, level, pos, newState, movedByPiston);
+    }
+
+    @Override
+    public InteractionResult useWithoutItem(BlockState state, Level level, BlockPos pos, Player player, BlockHitResult result) {
+
+        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer && level.getBlockEntity(pos) instanceof GravityTestBlockEntity testBlockEntity) {
+            serverPlayer.openMenu(new SimpleMenuProvider(testBlockEntity, Component.literal("Gravity Test Block")), pos);
+        }
+        return InteractionResult.sidedSuccess(level.isClientSide);
+    }
+}

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

@@ -0,0 +1,119 @@
+package net.xevianlight.aphelion.block.entity.custom;
+
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.network.chat.Component;
+import net.minecraft.network.protocol.game.ClientboundBlockEntityDataPacket;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.MenuProvider;
+import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.AbstractContainerMenu;
+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.neoforged.neoforge.items.ItemStackHandler;
+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.saveddata.GravitySavedData;
+import net.xevianlight.aphelion.screen.ElectricArcFurnaceMenu;
+import net.xevianlight.aphelion.screen.GravityTestBlockMenu;
+import net.xevianlight.aphelion.systems.GravityService;
+import org.jetbrains.annotations.Nullable;
+
+public class GravityTestBlockEntity extends BlockEntity implements TickableBlockEntity, MenuProvider {
+
+    public GravityTestBlockEntity(BlockPos pos, BlockState blockState) {super(ModBlockEntities.GRAVITY_TEST_BLOCK_ENTITY.get(), pos, blockState);}
+
+    public int areaSize = 5;
+    public float gravityStrength = 5f;
+    private boolean isInitialized = false;
+    public final ItemStackHandler inventory = new ItemStackHandler(0);
+
+    @Override
+    protected void saveAdditional(CompoundTag pTag, HolderLookup.Provider pRegistries) {
+        pTag.putInt("areaSize", areaSize);
+        pTag.putFloat("gravityStrength", gravityStrength);
+        super.saveAdditional(pTag, pRegistries);
+    }
+
+    @Override
+    protected void loadAdditional(CompoundTag pTag, HolderLookup.Provider pRegistries) {
+        areaSize = pTag.getInt("areaSize");
+        gravityStrength = pTag.getFloat("gravityStrength");
+        super.loadAdditional(pTag, pRegistries);
+    }
+
+    public void setRadius(float r) {
+        areaSize = (int) r;
+    }
+
+    public void setStrength(float s) {
+        gravityStrength = s;
+    }
+
+    public void addGravityArea() {
+        Level level = getLevel();
+        if (level != null && level.isClientSide()) return;
+
+        BlockPos pos = this.getBlockPos();
+
+        GravityService.setGravityArea((ServerLevel) level, pos, gravityStrength, areaSize);
+    }
+
+    public void removeGravityArea() {
+        Level level = getLevel();
+        if (level != null && level.isClientSide()) return;
+
+        BlockPos pos = this.getBlockPos();
+
+        GravityService.removeGravityArea((ServerLevel) level, pos);
+    }
+
+    @Override
+    public void tick(Level entityLevel, long time, BlockState blockState, BlockPos pos) {}
+
+    @Override
+    public void clientTick(ClientLevel level, long time, BlockState state, BlockPos pos) {}
+
+    @Override
+    public void serverTick(ServerLevel level, long time, BlockState state, BlockPos pos) {}
+
+    @Override
+    public boolean isInitialized() {
+        return isInitialized;
+    }
+
+    @Override
+    public void firstTick(Level level, BlockState state, BlockPos pos) { addGravityArea(); isInitialized = true; }
+
+    @Override
+    public @Nullable AbstractContainerMenu createMenu(int i, Inventory inventory, Player player) {
+        return new GravityTestBlockMenu(i, inventory, this);
+    }
+
+    @Override
+    public Component getDisplayName() {
+        return null;
+    }
+
+    public void sendUpdate() {
+        removeGravityArea();
+        addGravityArea();
+    }
+
+    @Override
+    public ClientboundBlockEntityDataPacket getUpdatePacket() {
+        return ClientboundBlockEntityDataPacket.create(this);
+    }
+
+
+    @Override
+    public CompoundTag getUpdateTag(HolderLookup.Provider registries) {
+        return this.saveCustomOnly(registries);
+    }
+}

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

@@ -42,6 +42,8 @@ public class OxygenTestRenderer implements BlockEntityRenderer<OxygenTestBlockEn
     // If in debug mode, renders a model made from the blocks
     // that are currently returned by toBlockPositions(OxygenTestBlockEntity).
     public void render(OxygenTestBlockEntity be, float partialTick, PoseStack poseStack, MultiBufferSource buffer, int packedLight, int packedOverlay) {
+        if (true) return; // i think this is all deprecated now
+
         // This bit's debug only, folks!
         if (!Minecraft.getInstance().gui.getDebugOverlay().showDebugScreen()) return;
 

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

@@ -0,0 +1,179 @@
+package net.xevianlight.aphelion.client;
+
+import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.VertexConsumer;
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
+import net.minecraft.core.BlockPos;
+import org.joml.Matrix4f;
+import org.joml.Vector3f;
+
+import java.util.Collection;
+import java.util.Set;
+
+public class DebugRenderUtils {
+
+    /// Utilities for dealing with longs instead of BlockPos
+    /// I am not actually sure if this is faster or not. it probably is
+    /// 99% sure that this breaks in edge cases
+    public static class LongPos {
+        private static final int PACKED_X_LENGTH = 26;
+        private static final int PACKED_Y_LENGTH = 12;
+        private static final int PACKED_Z_LENGTH = 26;
+        private static final long PACKED_X_MASK = 67108863L;
+        private static final long PACKED_Y_MASK = 4095L;
+        private static final long PACKED_Z_MASK = 67108863L;
+        private static final int Y_OFFSET = 0;
+        private static final int Z_OFFSET = 12;
+        private static final int X_OFFSET = 38;
+        private static final long Y_MAGIC = PACKED_Y_MASK << Y_OFFSET;
+        private static final long Z_MAGIC = PACKED_Z_MASK << Z_OFFSET;
+        private static final long X_MAGIC = PACKED_X_MASK << X_OFFSET;
+
+        // no safeguard for the maximum values, but those are
+        public static long above(long pos) {
+            long y = (((pos & Y_MAGIC) >> Y_OFFSET) + 1) << Y_OFFSET;
+            return (pos & (~Y_MAGIC)) | (y & Y_MAGIC);
+        }
+
+        public static long below(long pos) {
+            long y = (((pos & Y_MAGIC) >> Y_OFFSET) - 1) << Y_OFFSET;
+            return (pos & (~Y_MAGIC)) | (y & Y_MAGIC);
+        }
+
+        public static long north(long pos) {
+            long z = (((pos & Z_MAGIC) >> Z_OFFSET) - 1) << Z_OFFSET;
+            return (pos & (~Z_MAGIC)) | (z & Z_MAGIC);
+        }
+
+        public static long south(long pos) {
+            long z = (((pos & Z_MAGIC) >> Z_OFFSET) + 1) << Z_OFFSET;
+            return (pos & (~Z_MAGIC)) | (z & Z_MAGIC);
+        }
+
+        public static long east(long pos) {
+            long x = (((pos & X_MAGIC) >> X_OFFSET) + 1) << X_OFFSET;
+            return (pos & (~X_MAGIC)) | (x & X_MAGIC);
+        }
+
+        public static long west(long pos) {
+            long x = (((pos & X_MAGIC) >> X_OFFSET) - 1) << X_OFFSET;
+            return (pos & (~X_MAGIC)) | (x & X_MAGIC);
+        }
+
+        public static int getX(long pos) {
+            return BlockPos.getX(pos);
+        }
+
+        public static int getY(long pos) {
+            return BlockPos.getY(pos);
+        }
+
+        public static int getZ(long pos) {
+            return BlockPos.getZ(pos);
+        }
+    }
+
+    public static void drawSphere(PoseStack poseStack, VertexConsumer vc, Vector3f center, float radius) {
+
+        Matrix4f mat = poseStack.last().pose();
+
+        final int Y_SEGMENT_COUNT = 20;
+        for (int segmentY=0; segmentY < Y_SEGMENT_COUNT; segmentY++) {
+            double bottomAngle = (((double) segmentY / Y_SEGMENT_COUNT) - 0.5) * Math.PI;
+            double topAngle = (((double) (segmentY+1) / Y_SEGMENT_COUNT) - 0.5) * Math.PI;
+            float y0 =  (float) Math.sin(bottomAngle) * radius + center.y();
+            float y1 = (float) Math.sin(topAngle) * radius + center.y();
+            float bottomRadius = (float) Math.cos(bottomAngle) * radius;
+            float topRadius = (float) Math.cos(topAngle) * radius;
+
+            final int POLAR_SEGMENT_COUNT = 20;
+            for (int segmentP = 0; segmentP < POLAR_SEGMENT_COUNT; segmentP++) {
+                // "left" and "right" As viewed from outside the sphere
+                double leftAngle = (((double) segmentP / POLAR_SEGMENT_COUNT) - 1) * 2 * Math.PI;
+                double rightAngle = (((double) (segmentP+1) / POLAR_SEGMENT_COUNT) - 1) * 2 * Math.PI;
+                // Points have to wind CCW, so 0->1->2->3 is CCW.
+                // 0 and 1 use y0, 2 and 3 use y1.
+                float x0, x1, x2, x3, z0, z1, z2, z3;
+
+                x0 = (float) Math.cos(leftAngle) * bottomRadius + center.x();
+                x1 = (float) Math.cos(rightAngle) * bottomRadius + center.x();
+                x2 = (float) Math.cos(rightAngle) * topRadius + center.x();
+                x3 = (float) Math.cos(leftAngle) * topRadius + center.x();
+                z0 = (float) Math.sin(leftAngle) * bottomRadius + center.z();
+                z1 = (float) Math.sin(rightAngle) * bottomRadius + center.z();
+                z2 = (float) Math.sin(rightAngle) * topRadius + center.z();
+                z3 = (float) Math.sin(leftAngle) * topRadius + center.z();
+
+                // Draw the sphere quad
+                quad(mat, vc,
+                        x0, y0, z0,
+                        x1, y0, z1,
+                        x2, y1, z2,
+                        x3, y1, z3,
+                        0.7f, 0.2f, 0.2f, 0.5f);
+            }
+        }
+    }
+
+     // Sorry LOSERS, we only let FAST data structures in HERE.
+    public static void drawBlockArea(PoseStack poseStack, VertexConsumer vc, LongOpenHashSet blocks) {
+
+        for (long p : blocks) {
+
+
+            // Neighbor checks: only render faces exposed to non-oxygen
+            boolean up    = blocks.contains(LongPos.above(p));
+            boolean down  = blocks.contains(LongPos.below(p));
+            boolean north = blocks.contains(LongPos.north(p));
+            boolean south = blocks.contains(LongPos.south(p));
+            boolean east  = blocks.contains(LongPos.east(p));
+            boolean west  = blocks.contains(LongPos.west(p));
+
+            if (up && down && north && south && east && west) continue;
+
+            drawBlockFaces(poseStack, vc, p, up, down, north, south, east, west);
+        }
+    }
+
+    public static void drawBlockFaces(
+            PoseStack poseStack, VertexConsumer vc, long posAsLong,
+            boolean up, boolean down, boolean north, boolean south, boolean east, boolean west) {
+        final float eps = 0.0025f;
+        float x0 = LongPos.getX(posAsLong) + eps;
+        float y0 = LongPos.getY(posAsLong) + eps;
+        float z0 = LongPos.getZ(posAsLong) + eps;
+        float x1 = LongPos.getX(posAsLong) + 1 - eps;
+        float y1 = LongPos.getY(posAsLong) + 1 - eps;
+        float z1 = LongPos.getZ(posAsLong) + 1 - eps;
+
+        // Color (ARGB-ish but as floats)
+        float r = 0.2f, g = 0.8f, b = 1.0f, a = 0.18f;
+
+        Matrix4f mat = poseStack.last().pose();
+
+        // IMPORTANT: vertex winding should be consistent (counter-clockwise)
+        if (!up)    quad(mat, vc, x0,y1,z0,  x1,y1,z0,  x1,y1,z1,  x0,y1,z1,  r,g,b,a);
+        if (!down)  quad(mat, vc, x0,y0,z1,  x1,y0,z1,  x1,y0,z0,  x0,y0,z0,  r,g,b,a);
+
+        if (!north) quad(mat, vc, x1,y0,z0,  x0,y0,z0,  x0,y1,z0,  x1,y1,z0,  r,g,b,a);
+        if (!south) quad(mat, vc, x0,y0,z1,  x1,y0,z1,  x1,y1,z1,  x0,y1,z1,  r,g,b,a);
+
+        if (!east)  quad(mat, vc, x1,y0,z1,  x1,y0,z0,  x1,y1,z0,  x1,y1,z1,  r,g,b,a);
+        if (!west)  quad(mat, vc, x0,y0,z0,  x0,y0,z1,  x0,y1,z1,  x0,y1,z0,  r,g,b,a);
+    }
+
+    public static void quad(
+            Matrix4f mat, VertexConsumer vc,
+            float x0, float y0, float z0,
+            float x1, float y1, float z1,
+            float x2, float y2, float z2,
+            float x3, float y3, float z3,
+            float r, float g, float b, float a
+    ) {
+        // POSITION_COLOR format: ONLY position + color.
+        vc.addVertex(mat, x0, y0, z0).setColor(r, g, b, a);
+        vc.addVertex(mat, x1, y1, z1).setColor(r, g, b, a);
+        vc.addVertex(mat, x2, y2, z2).setColor(r, g, b, a);
+        vc.addVertex(mat, x3, y3, z3).setColor(r, g, b, a);
+    }
+}

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

@@ -0,0 +1,74 @@
+package net.xevianlight.aphelion.client;
+
+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 it.unimi.dsi.fastutil.longs.Long2IntMap;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.RenderStateShard;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.server.IntegratedServer;
+import net.minecraft.core.BlockPos;
+import net.neoforged.api.distmarker.Dist;
+import net.neoforged.bus.api.SubscribeEvent;
+import net.neoforged.fml.common.EventBusSubscriber;
+import net.neoforged.neoforge.client.event.RenderLevelStageEvent;
+import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.core.saveddata.GravitySavedData;
+import net.xevianlight.aphelion.core.saveddata.types.GravityData;
+
+@EventBusSubscriber(modid = Aphelion.MOD_ID, value = Dist.CLIENT)
+public class GravityDebugRender {
+    // Untextured translucent quads (POSITION_COLOR only)
+    private static final RenderType GRAVITY_FILL = RenderType.create(
+            "aphelion_gravity_fill",
+            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)
+                    .setWriteMaskState(RenderStateShard.COLOR_DEPTH_WRITE)
+                    .createCompositeState(true)
+    );
+
+    @SubscribeEvent
+    public static void onRenderLevel(RenderLevelStageEvent event) {
+        // One stage only (pick one that exists and looks good)
+        if (event.getStage() != RenderLevelStageEvent.Stage.AFTER_TRANSLUCENT_BLOCKS) return;
+
+        Minecraft mc = Minecraft.getInstance();
+        if (mc.level == null || mc.player == null) return;
+        if (!mc.gui.getDebugOverlay().showDebugScreen()) return;
+
+        PoseStack poseStack = event.getPoseStack();
+        var cam = mc.gameRenderer.getMainCamera();
+        var camPos = cam.getPosition();
+
+        poseStack.pushPose();
+        poseStack.translate(-camPos.x, -camPos.y, -camPos.z);
+
+        // I'm lazy, so i'm just gonna make this work on a singleplayer server and call it a day :P
+        IntegratedServer singleplayer = mc.getSingleplayerServer();
+        if (singleplayer == null) return;
+
+        MultiBufferSource.BufferSource bufferSource = mc.renderBuffers().bufferSource();
+        VertexConsumer vc = bufferSource.getBuffer(GRAVITY_FILL);
+
+        for (Long2IntMap.Entry gravityEntry : GravitySavedData.get(singleplayer.getLevel(mc.level.dimension()))._debug_getGravityData().long2IntEntrySet()) {
+            GravityData d = GravityData.unpack(gravityEntry.getIntValue());
+            BlockPos p = BlockPos.of(gravityEntry.getLongKey());
+
+            DebugRenderUtils.drawSphere(poseStack, vc, p.getCenter().toVector3f(), d.getRadius());
+        }
+
+        poseStack.popPose();
+        bufferSource.endBatch(GRAVITY_FILL);
+    }
+}

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

@@ -17,6 +17,8 @@ import net.neoforged.neoforge.client.event.RenderLevelStageEvent;
 import net.xevianlight.aphelion.Aphelion;
 import org.joml.Matrix4f;
 
+import java.util.Collection;
+
 @EventBusSubscriber(modid = Aphelion.MOD_ID, value = Dist.CLIENT)
 public final class OxygenDebugRender {
 
@@ -56,63 +58,9 @@ public final class OxygenDebugRender {
         MultiBufferSource.BufferSource bufferSource = mc.renderBuffers().bufferSource();
         VertexConsumer vc = bufferSource.getBuffer(OXYGEN_FILL);
 
-        // Render surface faces only (fast + pretty)
-        for (long l : ClientOxygenCache.OXYGEN) {
-            BlockPos p = BlockPos.of(l);
-            drawSurfaceFaces(poseStack, vc, p);
-        }
+        DebugRenderUtils.drawBlockArea(poseStack, vc, ClientOxygenCache.OXYGEN);
 
         poseStack.popPose();
         bufferSource.endBatch(OXYGEN_FILL);
     }
-
-    private static void drawSurfaceFaces(PoseStack poseStack, VertexConsumer vc, BlockPos p) {
-        // Neighbor checks: only render faces exposed to non-oxygen
-        boolean up    = ClientOxygenCache.OXYGEN.contains(p.above().asLong());
-        boolean down  = ClientOxygenCache.OXYGEN.contains(p.below().asLong());
-        boolean north = ClientOxygenCache.OXYGEN.contains(p.north().asLong());
-        boolean south = ClientOxygenCache.OXYGEN.contains(p.south().asLong());
-        boolean east  = ClientOxygenCache.OXYGEN.contains(p.east().asLong());
-        boolean west  = ClientOxygenCache.OXYGEN.contains(p.west().asLong());
-
-        if (up && down && north && south && east && west) return;
-
-        final float eps = 0.0025f;
-        float x0 = p.getX() + eps;
-        float y0 = p.getY() + eps;
-        float z0 = p.getZ() + eps;
-        float x1 = p.getX() + 1 - eps;
-        float y1 = p.getY() + 1 - eps;
-        float z1 = p.getZ() + 1 - eps;
-
-        // Color (ARGB-ish but as floats)
-        float r = 0.2f, g = 0.8f, b = 1.0f, a = 0.18f;
-
-        Matrix4f mat = poseStack.last().pose();
-
-        // IMPORTANT: vertex winding should be consistent (counter-clockwise)
-        if (!up)    quad(mat, vc, x0,y1,z0,  x1,y1,z0,  x1,y1,z1,  x0,y1,z1,  r,g,b,a);
-        if (!down)  quad(mat, vc, x0,y0,z1,  x1,y0,z1,  x1,y0,z0,  x0,y0,z0,  r,g,b,a);
-
-        if (!north) quad(mat, vc, x1,y0,z0,  x0,y0,z0,  x0,y1,z0,  x1,y1,z0,  r,g,b,a);
-        if (!south) quad(mat, vc, x0,y0,z1,  x1,y0,z1,  x1,y1,z1,  x0,y1,z1,  r,g,b,a);
-
-        if (!east)  quad(mat, vc, x1,y0,z1,  x1,y0,z0,  x1,y1,z0,  x1,y1,z1,  r,g,b,a);
-        if (!west)  quad(mat, vc, x0,y0,z0,  x0,y0,z1,  x0,y1,z1,  x0,y1,z0,  r,g,b,a);
-    }
-
-    private static void quad(
-            Matrix4f mat, VertexConsumer vc,
-            float x0, float y0, float z0,
-            float x1, float y1, float z1,
-            float x2, float y2, float z2,
-            float x3, float y3, float z3,
-            float r, float g, float b, float a
-    ) {
-        // POSITION_COLOR format: ONLY position + color.
-        vc.addVertex(mat, x0, y0, z0).setColor(r, g, b, a);
-        vc.addVertex(mat, x1, y1, z1).setColor(r, g, b, a);
-        vc.addVertex(mat, x2, y2, z2).setColor(r, g, b, a);
-        vc.addVertex(mat, x3, y3, z3).setColor(r, g, b, a);
-    }
 }

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

@@ -51,4 +51,9 @@ public class ModBlockEntities {
             BLOCK_ENTITIES.register("rocket_assembler_block_entity", () -> BlockEntityType.Builder.of(
                     RocketAssemblerBlockEntity::new, ModBlocks.ROCKET_ASSEMBLER_BLOCK.get()).build(null)
             );
+
+    public static final Supplier<BlockEntityType<GravityTestBlockEntity>> GRAVITY_TEST_BLOCK_ENTITY =
+            BLOCK_ENTITIES.register("gravity_test_block_entity", () -> BlockEntityType.Builder.of(
+                    GravityTestBlockEntity::new, ModBlocks.GRAVITY_TEST_BLOCK.get()).build(null)
+            );
 }

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

@@ -6,6 +6,7 @@ import net.neoforged.neoforge.registries.DeferredRegister;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.block.custom.*;
 import net.xevianlight.aphelion.block.dummy.VAFMultiblockDummyBlock;
+import net.xevianlight.aphelion.block.entity.custom.GravityTestBlockEntity;
 
 public class ModBlocks {
     public static final DeferredRegister.Blocks BLOCKS = DeferredRegister.createBlocks(Aphelion.MOD_ID);
@@ -20,4 +21,5 @@ public class ModBlocks {
     public static final  DeferredBlock<Block> VAF_MULTIBLOCK_DUMMY_BLOCK = BLOCKS.register("vaf_dummy_block", () -> new VAFMultiblockDummyBlock(VAFMultiblockDummyBlock.getProperties()));
     public static final DeferredBlock<Block> OXYGEN_TEST_BLOCK = BLOCKS.register("oxygen_test_block", () -> new OxygenTestBlock(OxygenTestBlock.getProperties()));
     public static final DeferredBlock<Block> ROCKET_ASSEMBLER_BLOCK = BLOCKS.register("rocket_assemblerblock", () -> new RocketAssemblerBlock(RocketAssemblerBlock.getProperties()));
+    public static final DeferredBlock<Block> GRAVITY_TEST_BLOCK = BLOCKS.register("gravity_test_block", () -> new GravityTestBlock(GravityTestBlock.getProperties()));
 }

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

@@ -36,6 +36,7 @@ public static final DeferredItem<Item> MUSIC_DISC_BIT_SHIFT = ITEMS.register("mu
     public static final DeferredItem<BlockItem> ARC_FURNACE_CASING_BLOCK = ITEMS.register("arc_furnace_casing", () -> new BlockItem(ModBlocks.ARC_FURNACE_CASING_BLOCK.get(), ArcFurnaceCasingBlock.getItemProperties()));
     public static final DeferredItem<BlockItem> VACUUM_ARC_FURNACE_CONTROLLER = ITEMS.register("vacuum_arc_furnace_controller", () -> new BlockItem(ModBlocks.VACUUM_ARC_FURNACE_CONTROLLER.get(), VacuumArcFurnaceController.getItemProperties()));
     public static final DeferredItem<BlockItem> OXYGEN_TEST_BLOCK = ITEMS.register("oxygen_test_block", () -> new BlockItem(ModBlocks.OXYGEN_TEST_BLOCK.get(), new Item.Properties()));
+    public static final DeferredItem<BlockItem> GRAVITY_TEST_BLOCK = ITEMS.register("gravity_test_block", () -> new BlockItem(ModBlocks.GRAVITY_TEST_BLOCK.get(), new Item.Properties()));
     public static final DeferredItem<BlockItem> LAUNCH_PAD = ITEMS.register("launch_pad", () -> new BlockItem(ModBlocks.LAUNCH_PAD.get(), LaunchPad.getItemProperties()));
 //    public static final DeferredItem<BlockItem> VAF_MULTIBLOCK_DUMMY_BLOCK = ITEMS.register("vaf_multiblock_dummy_block", () -> new BlockItem(ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get(), VAFMultiblockDummyBlock.getItemProperties()));
 }

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

@@ -32,12 +32,18 @@ import java.util.List;
  */
 public class GravitySavedData extends SavedData {
 
+    private Level level;
+
     private final Long2IntOpenHashMap gravityData = new Long2IntOpenHashMap();
 
     private static final String NAME = "aphelion_gravity";
 
-    public static GravitySavedData create() {
-        return new GravitySavedData();
+    public static GravitySavedData create(Level level) {
+        return new GravitySavedData(level);
+    }
+
+    public GravitySavedData(Level level) {
+        this.level = level;
     }
 
     @Override
@@ -60,18 +66,18 @@ public class GravitySavedData extends SavedData {
         return tag;
     }
 
-    public static GravitySavedData load(CompoundTag tag, HolderLookup.Provider lookupProvider) {
-        GravitySavedData data = create();
+    public static GravitySavedData load(CompoundTag tag, HolderLookup.Provider lookupProvider, Level level) {
+        GravitySavedData data = new GravitySavedData(level);
 
-        if (!tag.contains("Position", Tag.TAG_LONG_ARRAY) || !tag.contains("Value", Tag.TAG_INT_ARRAY)) { return data; }
+        if (!tag.contains("Position", Tag.TAG_LONG_ARRAY) || !tag.contains("Value", Tag.TAG_INT_ARRAY)) {
+            return data;
+        }
 
         long[] positions = tag.getLongArray("Position");
         int[] values = tag.getIntArray("Value");
-
         int length = Math.min(positions.length, values.length);
 
         data.gravityData.ensureCapacity(length);
-
         for (int i = 0; i < length; i++) {
             data.gravityData.put(positions[i], values[i]);
         }
@@ -81,7 +87,7 @@ public class GravitySavedData extends SavedData {
 
     private static final int ABSENT = Integer.MIN_VALUE;
 
-    public @Nullable GravityData getGravityRegionData (Level level, BlockPos center) {
+    public @Nullable GravityData getGravityRegionData (BlockPos center) {
         GravityData data = GravityData.unpack(gravityData.getOrDefault(center.asLong(), ABSENT));
         return data.pack() == ABSENT ? null : data;
     }
@@ -94,6 +100,9 @@ public class GravitySavedData extends SavedData {
         gravityData.put(pos.asLong(), data.pack());
     }
 
+    public Long2IntOpenHashMap _debug_getGravityData() {
+        return gravityData;
+    }
 
 
     /**
@@ -115,7 +124,7 @@ public class GravitySavedData extends SavedData {
      * Returns the strongest acceleration among all gravity regions that overlap this block position
      */
     public float getGravityMax (BlockPos pos) {
-        float max = 0;
+        float max = -1;
 
         List<GravityData> regions = getGravityRegions(pos);
 
@@ -124,6 +133,10 @@ public class GravitySavedData extends SavedData {
             if (accel > max) max = accel;
         }
 
+        if (max == -1) {
+            max = defaultGravity(this.level);
+        }
+
         return max;
     }
 
@@ -158,7 +171,10 @@ public class GravitySavedData extends SavedData {
 
     public static GravitySavedData get(ServerLevel level) {
         return level.getDataStorage().computeIfAbsent(
-                new Factory<>(GravitySavedData::create, GravitySavedData::load),
+                new Factory<>(
+                        () -> new GravitySavedData(level),
+                        (tag, provider) -> GravitySavedData.load(tag, provider, level)
+                ),
                 NAME
         );
     }

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

@@ -4,7 +4,8 @@ public class GravityData {
     private float accel;
     private float radius;
 
-    public static final float DEFAULT_GRAVITY = 9.80665f; // 1G
+    public static final float ONE_G = 9.80665f;
+    public static final float DEFAULT_GRAVITY = ONE_G; // 1G
     public static final float GRAVITY_PRECISION = 100.0f;
     public static final float RADIUS_PRECISION = 100.0f;
     public static final float MAX_RADIUS = Short.MAX_VALUE / RADIUS_PRECISION;

src/main/java/net/xevianlight/aphelion/datagen/ModBlockLootTableProvider.java

@@ -26,6 +26,8 @@ public class ModBlockLootTableProvider extends BlockLootSubProvider {
         dropSelf(ModBlocks.OXYGEN_TEST_BLOCK.get());
         dropOther(ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get(), ItemStack.EMPTY.getItem());
         dropSelf(ModBlocks.LAUNCH_PAD.get());
+        dropSelf(ModBlocks.GRAVITY_TEST_BLOCK.get());
+        dropSelf(ModBlocks.ROCKET_ASSEMBLER_BLOCK.get());
     }
 
     @Override

src/main/java/net/xevianlight/aphelion/datagen/ModBlockStateProvider.java

@@ -32,7 +32,9 @@ public class ModBlockStateProvider extends BlockStateProvider {
 //        blockItem(ModBlocks.LAUNCH_PAD);
 
         blockItem(ModBlocks.ARC_FURNACE_CASING_BLOCK);
+
         blockWithItem(ModBlocks.OXYGEN_TEST_BLOCK);
+        blockWithItem(ModBlocks.GRAVITY_TEST_BLOCK);
     }
 
     private void blockWithItem(DeferredBlock<?> deferredBlock) {

src/main/java/net/xevianlight/aphelion/event/ModBusEvents.java

@@ -13,10 +13,14 @@ import net.xevianlight.aphelion.block.entity.custom.ElectricArcFurnaceEntity;
 import net.xevianlight.aphelion.block.entity.custom.TestBlockEntity;
 import net.xevianlight.aphelion.block.entity.custom.VacuumArcFurnaceControllerEntity;
 import net.xevianlight.aphelion.core.init.ModBlockEntities;
+import net.xevianlight.aphelion.network.ClientPlayerStateUpdateHandler;
 import net.xevianlight.aphelion.network.RocketPayloadHandlers;
 import net.xevianlight.aphelion.network.PartitionPayloadHandler;
+import net.xevianlight.aphelion.network.UpdateGravityTestBlockHandler;
+import net.xevianlight.aphelion.network.packet.ClientPlayerStateUpdatePacket;
 import net.xevianlight.aphelion.network.packet.PartitionPayload;
 import net.xevianlight.aphelion.network.packet.RocketLaunchPayload;
+import net.xevianlight.aphelion.network.packet.UpdateGravityTestBlockPacket;
 
 @EventBusSubscriber(modid = Aphelion.MOD_ID)
 public class ModBusEvents {
@@ -49,5 +53,16 @@ public class ModBusEvents {
                 RocketPayloadHandlers::handleRocketLaunch
         );
 
+        registrar.playToClient(
+                ClientPlayerStateUpdatePacket.TYPE,
+                ClientPlayerStateUpdatePacket.STREAM_CODEC,
+                ClientPlayerStateUpdateHandler::handleDataOnMain
+                );
+
+        registrar.playToServer(
+                UpdateGravityTestBlockPacket.TYPE,
+                UpdateGravityTestBlockPacket.STREAM_CODEC,
+                UpdateGravityTestBlockHandler::handleDataOnMain
+                );
     }
 }

src/main/java/net/xevianlight/aphelion/mixins/common/EntityMixin.java

@@ -0,0 +1,67 @@
+package net.xevianlight.aphelion.mixins.common;
+
+import com.llamalad7.mixinextras.injector.wrapmethod.WrapMethod;
+import com.llamalad7.mixinextras.injector.wrapoperation.Operation;
+import com.llamalad7.mixinextras.sugar.Local;
+import net.minecraft.core.BlockPos;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.neoforged.neoforge.attachment.AttachmentHolder;
+import net.xevianlight.aphelion.systems.GravityService;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+import org.spongepowered.asm.mixin.injection.callback.LocalCapture;
+import org.spongepowered.asm.util.Locals;
+
+import java.io.ObjectOutputStream;
+
+@Mixin(Entity.class)
+public abstract class EntityMixin extends AttachmentHolder {
+
+
+    @Shadow
+    public float fallDistance;
+
+    // @At("RETURN") injects at all points IMMEDIATELY before a "return" opcode.
+    // Immediately before means IMMEDIATELY BEFORE,
+    // so even in a method like:
+    //
+    // return gravity;
+    //
+    // What's ACTUALLY happening is:
+    //
+    // $value = gravity;
+    // return $value;
+    //
+    // So, when we inject, we get:
+    //
+    // $value = gravity;
+    // [RETURN INJECT POINT]
+    // return $value;
+    //
+     // so we get to edit $value.
+    @Inject(method = "getGravity", at = @At("RETURN"), cancellable = true)
+    public void aphelion$getGravity(CallbackInfoReturnable<Double> cir) {
+        cir.setReturnValue(cir.getReturnValue() * GravityService.getGravityFactor((Entity) (Object) this));
+    }
+
+    // Should only break if the code that increases fall distance is moved outside Entity$checkFallDamage.
+    @WrapMethod(method = "checkFallDamage")
+    public void aphelion$checkFallDamage(double y, boolean onGround, BlockState state, BlockPos pos, Operation<Void> original) {
+        float prevFallDistance = this.fallDistance;
+
+        original.call(y, onGround, state, pos);
+
+        float newFallDistance = this.fallDistance;
+        if (newFallDistance > prevFallDistance && newFallDistance > 0) {
+            float fallDistanceGained = newFallDistance - prevFallDistance;
+            this.fallDistance = prevFallDistance + (fallDistanceGained * Math.min(GravityService.getGravityFactor((Entity) (Object) this), 1));
+        }
+    }
+}

src/main/java/net/xevianlight/aphelion/mixins/common/LivingEntityMixin.java

@@ -5,6 +5,8 @@ import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.EntityType;
 import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.phys.Vec3;
+import net.xevianlight.aphelion.systems.GravityService;
 import net.xevianlight.aphelion.systems.OxygenService;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
@@ -26,4 +28,10 @@ public abstract class LivingEntityMixin extends Entity {
             OxygenService.entityTick(level, entity);
         }
     }
+
+    @Inject(method = "travel", at = @At("HEAD"))
+    public void aphelion$travel(Vec3 travelVector, CallbackInfo ci) {
+        // temporarily disabled in favor of aphelion$getGravity mixin
+        //if (this.isControlledByLocalInstance()) GravityService.onEntityTravel(level(), (LivingEntity) (Object) this);
+    }
 }

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

@@ -0,0 +1,42 @@
+package net.xevianlight.aphelion.network;
+
+import net.minecraft.world.entity.player.Player;
+import net.xevianlight.aphelion.core.saveddata.types.GravityData;
+import net.xevianlight.aphelion.systems.GravityService;
+import net.xevianlight.aphelion.systems.OxygenService;
+
+/// Read-only player state object; updated by a server packet every so often
+public record ClientPlayerState(boolean oxygen, float gravity, float temperature) {
+    // Default player state
+    private static ClientPlayerState localData = new ClientPlayerState(true, GravityData.DEFAULT_GRAVITY * 0.5f, 50f);
+
+    public static void updateState(ClientPlayerState newData) {
+        onStateUpdate(localData, newData);
+        localData = newData;
+    }
+
+    public static ClientPlayerState getServerStateOf(Player player) {
+        return new ClientPlayerState(OxygenService.hasOxygen(player), GravityService.getGravityAccel(player), 50f);
+    }
+
+    /// For things like playing SFX, VFX, etc. etc.
+    public static void onStateUpdate(ClientPlayerState oldData, ClientPlayerState newData) {
+        // TODO: add sfx
+        if (!oldData.oxygen() && newData.oxygen()) {
+            // On oxygen gained
+        }
+        if (oldData.oxygen() && !newData.oxygen()) {
+            // On oxygen removed
+        }
+        if (newData.gravity() - 0.25f > oldData.gravity()) {
+            // On gravity increased by > 0.25
+        }
+        if (oldData.gravity() - 0.25f > newData.gravity()) {
+            // On gravity decreased by > 0.25
+        }
+    }
+
+    public static ClientPlayerState getLocalData() {
+        return localData;
+    }
+}

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

@@ -0,0 +1,11 @@
+package net.xevianlight.aphelion.network;
+
+import net.neoforged.neoforge.network.handling.IPayloadContext;
+import net.xevianlight.aphelion.network.packet.ClientPlayerStateUpdatePacket;
+
+public class ClientPlayerStateUpdateHandler {
+
+    public static void handleDataOnMain(ClientPlayerStateUpdatePacket packet, IPayloadContext context) {
+        context.enqueueWork(() -> ClientPlayerState.updateState(new ClientPlayerState(packet.oxygen(), packet.gravity(), packet.temp())));
+    }
+}

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

@@ -2,12 +2,16 @@ package net.xevianlight.aphelion.network;
 
 
 import net.minecraft.client.Minecraft;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.entity.player.Player;
 import net.neoforged.bus.api.SubscribeEvent;
 import net.neoforged.fml.common.EventBusSubscriber;
 import net.neoforged.neoforge.client.event.ClientTickEvent;
+import net.neoforged.neoforge.event.tick.ServerTickEvent;
 import net.neoforged.neoforge.network.PacketDistributor;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.entites.vehicles.RocketEntity;
+import net.xevianlight.aphelion.network.packet.ClientPlayerStateUpdatePacket;
 import net.xevianlight.aphelion.network.packet.RocketLaunchPayload;
 
 import net.xevianlight.aphelion.client.AphelionClient;
@@ -27,4 +31,17 @@ public final class KeyNetwork {
             PacketDistributor.sendToServer(new RocketLaunchPayload(rocket.getId()));
         }
     }
+
+    @SubscribeEvent
+    public static void onServerTick(ServerTickEvent.Post event) {
+        int FREQ = 4;
+        for (ServerPlayer p : event.getServer().getPlayerList().getPlayers()) {
+            if (p.tickCount % FREQ == 0) {
+                ClientPlayerState state = ClientPlayerState.getServerStateOf(p);
+
+                PacketDistributor.sendToPlayer(p, new ClientPlayerStateUpdatePacket(state.oxygen(), state.gravity(), state.temperature()));
+            }
+        }
+
+    }
 }

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

@@ -0,0 +1,27 @@
+package net.xevianlight.aphelion.network;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.neoforged.neoforge.network.handling.IPayloadContext;
+import net.xevianlight.aphelion.block.entity.custom.GravityTestBlockEntity;
+import net.xevianlight.aphelion.network.packet.UpdateGravityTestBlockPacket;
+
+public class UpdateGravityTestBlockHandler {
+    public static void handleDataOnMain(UpdateGravityTestBlockPacket packet, IPayloadContext context) {
+        context.enqueueWork(() -> {
+            BlockPos pos = packet.pos();
+            float radius = packet.radius();
+            float strength = packet.strength();
+
+            Level level = context.player().level();
+            if (level.getBlockEntity(pos) instanceof GravityTestBlockEntity blockEntity) {
+                blockEntity.setRadius(radius);
+                blockEntity.setStrength(strength);
+                blockEntity.sendUpdate();
+                level.sendBlockUpdated(pos, level.getBlockState(pos), level.getBlockState(pos), Block.UPDATE_ALL);
+            }
+        });
+    }
+}

src/main/java/net/xevianlight/aphelion/network/packet/ClientPlayerStateUpdatePacket.java

@@ -0,0 +1,29 @@
+package net.xevianlight.aphelion.network.packet;
+
+import io.netty.buffer.ByteBuf;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.resources.ResourceLocation;
+import net.xevianlight.aphelion.Aphelion;
+
+public record ClientPlayerStateUpdatePacket(boolean oxygen, float gravity, float temp) implements CustomPacketPayload {
+    public static final CustomPacketPayload.Type<ClientPlayerStateUpdatePacket> TYPE = new CustomPacketPayload.Type<>(ResourceLocation.fromNamespaceAndPath(Aphelion.MOD_ID, "player_state_update"));
+
+    public static final StreamCodec<ByteBuf, ClientPlayerStateUpdatePacket> STREAM_CODEC = StreamCodec.composite(
+            ByteBufCodecs.BOOL,
+            ClientPlayerStateUpdatePacket::oxygen,
+            ByteBufCodecs.FLOAT,
+            ClientPlayerStateUpdatePacket::gravity,
+            ByteBufCodecs.FLOAT,
+            ClientPlayerStateUpdatePacket::temp,
+            ClientPlayerStateUpdatePacket::new
+    );
+
+    @Override
+    public CustomPacketPayload.Type<? extends CustomPacketPayload> type() {
+        return TYPE;
+    }
+
+
+}

src/main/java/net/xevianlight/aphelion/network/packet/UpdateGravityTestBlockPacket.java

@@ -0,0 +1,30 @@
+package net.xevianlight.aphelion.network.packet;
+
+import io.netty.buffer.ByteBuf;
+import net.minecraft.core.BlockPos;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.resources.ResourceLocation;
+import net.xevianlight.aphelion.Aphelion;
+
+public record UpdateGravityTestBlockPacket(BlockPos pos, float radius, float strength) implements CustomPacketPayload {
+
+    public static final CustomPacketPayload.Type<UpdateGravityTestBlockPacket> TYPE =
+            new CustomPacketPayload.Type<>(ResourceLocation.fromNamespaceAndPath(Aphelion.MOD_ID, "update_oxygen_test_block"));
+
+    public static final StreamCodec<ByteBuf, UpdateGravityTestBlockPacket> STREAM_CODEC = StreamCodec.composite(
+            BlockPos.STREAM_CODEC,
+            UpdateGravityTestBlockPacket::pos,
+            ByteBufCodecs.FLOAT,
+            UpdateGravityTestBlockPacket::radius,
+            ByteBufCodecs.FLOAT,
+            UpdateGravityTestBlockPacket::strength,
+            UpdateGravityTestBlockPacket::new
+    );
+
+    @Override
+    public CustomPacketPayload.Type<? extends CustomPacketPayload> type() {
+        return TYPE;
+    }
+}

src/main/java/net/xevianlight/aphelion/screen/GravityTestBlockMenu.java

@@ -0,0 +1,110 @@
+package net.xevianlight.aphelion.screen;
+
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.AbstractContainerMenu;
+import net.minecraft.world.inventory.BrewingStandMenu;
+import net.minecraft.world.inventory.Slot;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.neoforged.neoforge.items.SlotItemHandler;
+import net.xevianlight.aphelion.block.entity.custom.GravityTestBlockEntity;
+import net.xevianlight.aphelion.block.entity.custom.TestBlockEntity;
+import org.jetbrains.annotations.NotNull;
+
+public class GravityTestBlockMenu extends AbstractContainerMenu {
+    public final GravityTestBlockEntity blockEntity;
+    private final Level level;
+
+    public GravityTestBlockMenu(int i, Inventory inventory, FriendlyByteBuf extraData) {
+        this(i, inventory, inventory.player.level().getBlockEntity(extraData.readBlockPos()));
+    }
+
+    public GravityTestBlockMenu(int i, Inventory inventory, BlockEntity blockEntity) {
+        super(ModMenuTypes.GRAVITY_TEST_BLOCK_MENU.get(), i);
+        this.blockEntity = ((GravityTestBlockEntity) blockEntity);
+        this.level = inventory.player.level();
+
+        // Init stuff
+        addPlayerInventory(inventory);
+        addPlayerHotbar(inventory);
+
+
+    }
+
+    @Override
+    public boolean stillValid(Player player) {
+        return true;
+    }
+
+    // CREDIT GOES TO: diesieben07 | https://github.com/diesieben07/SevenCommons
+    // must assign a slot number to each of the slots used by the GUI.
+    // For this container, we can see both the tile inventory's slots as well as the player inventory slots and the hotbar.
+    // Each time we add a Slot to the container, it automatically increases the slotIndex, which means
+    //  0 - 8 = hotbar slots (which will map to the InventoryPlayer slot numbers 0 - 8)
+    //  9 - 35 = player inventory slots (which map to the InventoryPlayer slot numbers 9 - 35)
+    //  36 - 44 = TileInventory slots, which map to our TileEntity slot numbers 0 - 8)
+    private static final int HOTBAR_SLOT_COUNT = 9;
+    private static final int PLAYER_INVENTORY_ROW_COUNT = 3;
+    private static final int PLAYER_INVENTORY_COLUMN_COUNT = 9;
+    private static final int PLAYER_INVENTORY_SLOT_COUNT = PLAYER_INVENTORY_COLUMN_COUNT * PLAYER_INVENTORY_ROW_COUNT;
+    private static final int VANILLA_SLOT_COUNT = HOTBAR_SLOT_COUNT + PLAYER_INVENTORY_SLOT_COUNT;
+    private static final int VANILLA_FIRST_SLOT_INDEX = 0;
+    private static final int TE_INVENTORY_FIRST_SLOT_INDEX = VANILLA_FIRST_SLOT_INDEX + VANILLA_SLOT_COUNT;
+
+    // THIS YOU HAVE TO DEFINE!
+    private static final int TE_INVENTORY_SLOT_COUNT = 0;  // must be the number of slots you have!
+    @Override
+    public @NotNull ItemStack quickMoveStack(Player playerIn, int pIndex) {
+        Slot sourceSlot = slots.get(pIndex);
+        if (sourceSlot == null || !sourceSlot.hasItem()) return ItemStack.EMPTY;  //EMPTY_ITEM
+        ItemStack sourceStack = sourceSlot.getItem();
+        ItemStack copyOfSourceStack = sourceStack.copy();
+
+        // Check if the slot clicked is one of the vanilla container slots
+        if (pIndex < VANILLA_FIRST_SLOT_INDEX + VANILLA_SLOT_COUNT) {
+            // This is a vanilla container slot so merge the stack into the tile inventory
+            if (!moveItemStackTo(sourceStack, TE_INVENTORY_FIRST_SLOT_INDEX, TE_INVENTORY_FIRST_SLOT_INDEX
+                    + TE_INVENTORY_SLOT_COUNT, false)) {
+                blockEntity.sendUpdate();
+                return ItemStack.EMPTY;  // EMPTY_ITEM
+            }
+        } else if (pIndex < TE_INVENTORY_FIRST_SLOT_INDEX + TE_INVENTORY_SLOT_COUNT) {
+            // This is a TE slot so merge the stack into the players inventory
+            if (!moveItemStackTo(sourceStack, VANILLA_FIRST_SLOT_INDEX, VANILLA_FIRST_SLOT_INDEX + VANILLA_SLOT_COUNT, false)) {
+                blockEntity.sendUpdate();
+                return ItemStack.EMPTY;
+            }
+        } else {
+            System.out.println("Invalid slotIndex:" + pIndex);
+            return ItemStack.EMPTY;
+        }
+        // If stack size == 0 (the entire stack was moved) set slot contents to null
+        if (sourceStack.getCount() == 0) {
+            sourceSlot.set(ItemStack.EMPTY);
+            blockEntity.sendUpdate();
+        } else {
+            blockEntity.sendUpdate();
+            sourceSlot.setChanged();
+        }
+        sourceSlot.onTake(playerIn, sourceStack);
+        blockEntity.sendUpdate();
+        return copyOfSourceStack;
+    }
+
+    private void addPlayerInventory(Inventory playerInventory) {
+        for (int i = 0; i < 3; ++i) {
+            for (int l = 0; l < 9; ++l) {
+                this.addSlot(new Slot(playerInventory, l + i * 9 + 9, 8 + l * 18, 84 + i * 18));
+            }
+        }
+    }
+
+    private void addPlayerHotbar(Inventory playerInventory) {
+        for (int i = 0; i < 9; ++i) {
+            this.addSlot(new Slot(playerInventory, i, 8 + i * 18, 142));
+        }
+    }
+}

src/main/java/net/xevianlight/aphelion/screen/GravityTestBlockScreen.java

@@ -0,0 +1,94 @@
+package net.xevianlight.aphelion.screen;
+
+import com.mojang.blaze3d.systems.RenderSystem;
+import net.minecraft.client.gui.GuiGraphics;
+import net.minecraft.client.gui.components.Button;
+import net.minecraft.client.gui.components.StringWidget;
+import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
+import net.minecraft.client.gui.screens.inventory.FurnaceScreen;
+import net.minecraft.client.renderer.GameRenderer;
+import net.minecraft.network.chat.Component;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.entity.player.Inventory;
+import net.neoforged.neoforge.network.PacketDistributor;
+import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.network.packet.UpdateGravityTestBlockPacket;
+
+public class GravityTestBlockScreen extends AbstractContainerScreen<GravityTestBlockMenu> {
+
+    private static final ResourceLocation GUI_TEXTURE =
+            ResourceLocation.fromNamespaceAndPath(Aphelion.MOD_ID, "textures/gui/gravity_test_block/gui.png");
+
+    public GravityTestBlockScreen(GravityTestBlockMenu menu, Inventory playerInventory, Component title) {
+        super(menu, playerInventory, title);
+    }
+
+    private StringWidget gravityWidget;
+    private StringWidget rangeWidget;
+
+    @Override
+    protected void init() {
+        super.init();
+
+        // Gets rid of labels
+        this.inventoryLabelY = 73;
+        this.titleLabelY = 5;
+
+        // Increase Gravity
+        this.addRenderableWidget(Button.builder(Component.literal("+"), (button) -> {
+            PacketDistributor.sendToServer(new UpdateGravityTestBlockPacket(menu.blockEntity.getBlockPos(), menu.blockEntity.areaSize, menu.blockEntity.gravityStrength + 0.1f));
+        }).bounds(this.leftPos + 7, this.topPos + 30, 9, 9).build());
+        // Decrease Gravity
+        this.addRenderableWidget(Button.builder(Component.literal("-"), (button) -> {
+            PacketDistributor.sendToServer(new UpdateGravityTestBlockPacket(menu.blockEntity.getBlockPos(), menu.blockEntity.areaSize, menu.blockEntity.gravityStrength - 0.1f));
+        }).bounds(this.leftPos + 19, this.topPos + 30, 9, 9).build());
+        // Increase Radius
+        this.addRenderableWidget(Button.builder(Component.literal("+"), (button) -> {
+            PacketDistributor.sendToServer(new UpdateGravityTestBlockPacket(menu.blockEntity.getBlockPos(), menu.blockEntity.areaSize + 1, menu.blockEntity.gravityStrength));
+        }).bounds(this.leftPos + 135, this.topPos + 32, 9, 9).build());
+        // Decrease Radius
+        this.addRenderableWidget(Button.builder(Component.literal("-"), (button) -> {
+            PacketDistributor.sendToServer(new UpdateGravityTestBlockPacket(menu.blockEntity.getBlockPos(), menu.blockEntity.areaSize - 1, menu.blockEntity.gravityStrength));
+        }).bounds(this.leftPos + 147, this.topPos + 32, 9, 9).build());
+
+        // Current Gravity
+        gravityWidget = new StringWidget(
+                this.leftPos + 11,
+                this.topPos+46,
+                26,
+                9,
+                Component.literal("" + menu.blockEntity.gravityStrength),
+                this.font);
+        this.addRenderableWidget(gravityWidget);
+
+        // Current Radius
+        rangeWidget = new StringWidget(
+                this.leftPos + 139,
+                this.topPos+46,
+                26,
+                9,
+                Component.literal("" + menu.blockEntity.areaSize),
+                this.font);
+        this.addRenderableWidget(rangeWidget);
+    }
+
+    @Override
+    protected void renderBg(GuiGraphics pGuiGraphics, float pPartialTick, int pMouseX, int pMouseY) {
+        RenderSystem.setShader(GameRenderer::getPositionTexShader);
+        RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1.0F);
+        RenderSystem.setShaderTexture(0, GUI_TEXTURE);
+        int x = (width - imageWidth) / 2;
+        int y = (height - imageHeight) / 2;
+
+        pGuiGraphics.blit(GUI_TEXTURE, x, y, 0, 0, imageWidth, imageHeight);
+    }
+
+    @Override
+    public void render(GuiGraphics guiGraphics, int mouseX, int mouseY, float delta) {
+        renderBackground(guiGraphics, mouseX, mouseY, delta);
+        super.render(guiGraphics, mouseX, mouseY, delta);
+        renderTooltip(guiGraphics, mouseX, mouseY);
+        gravityWidget.setMessage(Component.literal(String.format("%.1f", menu.blockEntity.gravityStrength)));
+        rangeWidget.setMessage(Component.literal("" + menu.blockEntity.areaSize));
+    }
+}

src/main/java/net/xevianlight/aphelion/screen/ModMenuTypes.java

@@ -10,6 +10,8 @@ import net.neoforged.neoforge.registries.DeferredHolder;
 import net.neoforged.neoforge.registries.DeferredRegister;
 import net.xevianlight.aphelion.Aphelion;
 
+import java.awt.*;
+
 public class ModMenuTypes {
     public static final DeferredRegister<MenuType<?>> MENUS =
             DeferredRegister.create(Registries.MENU, Aphelion.MOD_ID);
@@ -23,6 +25,9 @@ public class ModMenuTypes {
     public static DeferredHolder<MenuType<?>,MenuType<VacuumArcFurnaceMenu>> VACUUM_ARC_FURNACE_MENU =
             registerMenuType("vacuum_arc_furnace_menu", VacuumArcFurnaceMenu::new);
 
+    public static DeferredHolder<MenuType<?>,MenuType<GravityTestBlockMenu>> GRAVITY_TEST_BLOCK_MENU =
+            registerMenuType("gravity_test_block_menu", GravityTestBlockMenu::new);
+
     private static <T extends AbstractContainerMenu>DeferredHolder<MenuType<?>, MenuType<T>> registerMenuType(String name,
                                                                                                               IContainerFactory<T> factory) {
         return MENUS.register(name, () -> IMenuTypeExtension.create(factory));

src/main/java/net/xevianlight/aphelion/systems/GravityService.java

@@ -0,0 +1,79 @@
+package net.xevianlight.aphelion.systems;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.effect.MobEffects;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.phys.Vec3;
+import net.xevianlight.aphelion.network.ClientPlayerState;
+import net.xevianlight.aphelion.core.saveddata.GravitySavedData;
+import net.xevianlight.aphelion.core.saveddata.types.GravityData;
+
+public class GravityService {
+
+    public static void setGravityArea(ServerLevel level, BlockPos pos, float accel, int radius) {
+        GravitySavedData.get(level).setGravityRegion(pos, new GravityData(accel, radius));
+    }
+
+    public static void removeGravityArea(ServerLevel level, BlockPos pos) {
+        GravitySavedData.get(level).removeGravityRegion(pos);
+    }
+
+    public static float getGravityAccel(Level level, BlockPos pos) {
+        if (level.isClientSide) {
+            // Pull from the client data b/c we can't access the server's saved data
+            return ClientPlayerState.getLocalData().gravity();
+        }
+        // TODO: maybe change this based on how stuff pans out
+        var gravity = GravitySavedData.get((ServerLevel) level).getGravityMax(pos);
+
+        return gravity;
+    }
+
+    public static float getGravityAccel(Entity entity) {
+        // Not sure if this is at the entity's feet, head, or the middle... research later
+        // Blockpos is from entity's feet ~Xev
+        BlockPos entityBlockPos = BlockPos.containing(entity.getX(), entity.getY(), entity.getZ());
+        return getGravityAccel(entity.level(), entityBlockPos);
+    }
+
+    public static float getGravityFactor(Entity entity) {
+        float gravityAccelReal = getGravityAccel(entity);
+
+        // How many times normal gravity you're experiencing.
+        // "normal gravity" varies across different entities. Thankfully, minecraft slaps a "protected" status
+        // on LivingEntity.getGravity(), so i graciously get to go fuck myself and not care.
+        // Players are 0.08 units/second/travel() of gravity (from what i've gathered)
+        return gravityAccelReal / GravityData.ONE_G;
+    }
+
+    /// Called by LivingEntity$travel mixin
+    public static void onEntityTravel(Level level, LivingEntity entity) {
+        if (
+                entity.isFallFlying() || entity.isInLiquid() ||
+                entity.isUnderWater() ||
+                entity.hasEffect(MobEffects.SLOW_FALLING)
+        ) return;
+
+        float gravityAccelReal = getGravityAccel(entity);
+
+        // How many times normal gravity you're experiencing.
+        // "normal gravity" varies across different entities. Thankfully, minecraft slaps a "protected" status
+        // on LivingEntity.getGravity(), so i graciously get to go fuck myself and not care.
+        // Players are 0.08 units/second/travel() of gravity (from what i've gathered)
+        float gravityFactor = gravityAccelReal / GravityData.ONE_G;
+
+        // NOTE: this might cause certain entities to fly into the stratosphere at ultra low gravity,
+        // seeing as this isn't the same for all entities.
+        // Thankfully, though, this should have no effect on anything at default gravity.
+        float baseGameGravityAccel = 0.08f;
+        float translatedAccel = baseGameGravityAccel * gravityFactor;
+
+        Vec3 currentVelocity = entity.getDeltaMovement();
+        // add baseGameGravity to cancel normal gravity, then subtract the new gravity
+        if (translatedAccel > 0) entity.setDeltaMovement(currentVelocity.x(), currentVelocity.y() + (baseGameGravityAccel - translatedAccel), currentVelocity.z());
+        else entity.setDeltaMovement(currentVelocity.x(), currentVelocity.y() + baseGameGravityAccel, currentVelocity.z());
+    }
+}

src/main/resources/aphelion.mixins.json

@@ -4,6 +4,7 @@
   "package": "net.xevianlight.aphelion.mixins",
   "compatibilityLevel": "JAVA_21",
   "mixins": [
+    "common.EntityMixin",
     "common.LivingEntityMixin"
   ],
   "client": [

src/main/resources/data/aphelion/planet/overworld.json

@@ -2,6 +2,6 @@
   "dimension": "minecraft:overworld",
   "orbit_distance": 1,
   "star_system": "aphelon:sol",
-  "gravity": 1,
+  "gravity": 9.8,
   "oxygen": false
 }