Physics rewrite for better gravity manipulation

src/main/java/com/minelittlepony/unicopia/ability/AbilityDispatcher.java

@@ -8,7 +8,6 @@ import javax.annotation.Nullable;
 
 import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.data.Hit;
-import com.minelittlepony.unicopia.entity.Updatable;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.network.MsgPlayerAbility;
 import com.minelittlepony.unicopia.network.Channel;
@@ -16,8 +15,9 @@ import com.minelittlepony.unicopia.util.NbtSerialisable;
 
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.util.Identifier;
+import net.minecraft.util.Tickable;
 
-public class AbilityDispatcher implements Updatable, NbtSerialisable {
+public class AbilityDispatcher implements Tickable, NbtSerialisable {
 
     private final Pony player;
 
@@ -88,7 +88,7 @@ public class AbilityDispatcher implements Updatable, NbtSerialisable {
     }
 
     @Override
-    public void onUpdate() {
+    public void tick() {
         getActiveAbility().ifPresent(this::activate);
     }
 

src/main/java/com/minelittlepony/unicopia/ability/CarryAbility.java

@@ -28,8 +28,8 @@ public class CarryAbility implements Ability<Hit> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies.canFly();
+    public boolean canUse(Race race) {
+        return race.canFly();
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/ChangelingDisguiseAbility.java

@@ -74,7 +74,7 @@ public class ChangelingDisguiseAbility extends ChangelingFeedAbility {
             return disc;
         }).setDisguise(looked);
 
-        iplayer.sendCapabilities(true);
+        iplayer.setDirty();
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/ChangelingFeedAbility.java

@@ -42,8 +42,8 @@ public class ChangelingFeedAbility implements Ability<Hit> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies == Race.CHANGELING;
+    public boolean canUse(Race race) {
+        return race == Race.CHANGELING;
     }
 
     @Nullable

src/main/java/com/minelittlepony/unicopia/ability/EarthPonyGrowAbility.java

@@ -33,8 +33,8 @@ public class EarthPonyGrowAbility implements Ability<Pos> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies == Race.EARTH;
+    public boolean canUse(Race race) {
+        return race == Race.EARTH;
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/EarthPonyStompAbility.java

@@ -64,8 +64,8 @@ public class EarthPonyStompAbility implements Ability<Multi> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies.canUseEarth();
+    public boolean canUse(Race race) {
+        return race.canUseEarth();
     }
 
     @Nullable

src/main/java/com/minelittlepony/unicopia/ability/PegasusCloudInteractionAbility.java

@@ -25,8 +25,8 @@ public class PegasusCloudInteractionAbility implements Ability<Numeric> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies.canInteractWithClouds();
+    public boolean canUse(Race race) {
+        return race.canInteractWithClouds();
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/UnicornCastingAbility.java

@@ -23,8 +23,8 @@ public class UnicornCastingAbility implements Ability<Hit> {
     }
 
     @Override
-    public boolean canUse(Race playerSpecies) {
-        return playerSpecies.canCast();
+    public boolean canUse(Race race) {
+        return race.canCast();
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/client/render/WorldRenderDelegate.java

@@ -0,0 +1,67 @@
+package com.minelittlepony.unicopia.client.render;
+
+import com.minelittlepony.unicopia.entity.player.Pony;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.util.math.MatrixStack;
+import net.minecraft.client.util.math.Vector3f;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.player.PlayerEntity;
+
+public class WorldRenderDelegate {
+
+    public static final WorldRenderDelegate INSTANCE = new WorldRenderDelegate();
+
+    public void beforeEntityRender(Pony pony, MatrixStack matrices, double x, double y, double z) {
+        if (pony.getPhysics().isGravityNegative()) {
+            matrices.push();
+
+            Entity entity = pony.getOwner();
+
+            matrices.translate(x, y, z);
+            matrices.translate(0, entity.getHeight(), 0);
+            matrices.multiply(Vector3f.POSITIVE_Z.getDegreesQuaternion(180));
+            matrices.translate(-x, -y, -z);
+
+            flipAngles(entity);
+        }
+    }
+
+    public void afterEntityRender(Pony pony, MatrixStack matrices) {
+        if (pony.getPhysics().isGravityNegative()) {
+            matrices.pop();
+
+            flipAngles(pony.getOwner());
+
+        }
+    }
+
+    private void flipAngles(Entity entity) {
+        if (MinecraftClient.getInstance().options.perspective > 0) {
+            entity.prevYaw *= -1;
+            entity.yaw *= -1;
+
+            if (entity instanceof LivingEntity) {
+                LivingEntity living = (LivingEntity)entity;
+
+                living.bodyYaw = -living.bodyYaw;
+                living.prevBodyYaw = -living.prevBodyYaw;
+                living.headYaw = -living.headYaw;
+                living.prevHeadYaw = -living.prevHeadYaw;
+            }
+        }
+        entity.prevPitch *= -1;
+        entity.pitch *= -1;
+    }
+
+    public void applyWorldTransform(MatrixStack matrices, float tickDelta) {
+        PlayerEntity player = MinecraftClient.getInstance().player;
+
+        if (player != null && MinecraftClient.getInstance().cameraEntity == player) {
+            float roll = Pony.of(player).getCamera().calculateRoll();
+
+            matrices.multiply(Vector3f.POSITIVE_Z.getDegreesQuaternion(roll));
+        }
+    }
+}

src/main/java/com/minelittlepony/unicopia/command/GravityCommand.java

@@ -39,7 +39,7 @@ class GravityCommand {
 
         Pony iplayer = Pony.of(player);
 
-        float gravity = iplayer.getGravity().getGravitationConstant();
+        float gravity = iplayer.getPhysics().getGravityModifier();
 
         if (source.getPlayer() != player) {
             translationKey += ".other";
@@ -54,8 +54,8 @@ class GravityCommand {
 
         Pony iplayer = Pony.of(player);
 
-        iplayer.getGravity().setGraviationConstant(gravity);
-        iplayer.sendCapabilities(true);
+        iplayer.getPhysics().setGravityModifier(gravity);
+        iplayer.setDirty();
 
         if (isSelf) {
             player.sendMessage(new TranslatableText(translationKey, gravity));

src/main/java/com/minelittlepony/unicopia/command/SpeciesCommand.java

@@ -49,7 +49,7 @@ class SpeciesCommand {
         if (race.isPermitted(player)) {
             Pony pony = Pony.of(player);
             pony.setSpecies(race);
-            pony.sendCapabilities(false);
+            pony.setDirty();
 
             Text formattedName = new TranslatableText(race.name().toLowerCase());
 

src/main/java/com/minelittlepony/unicopia/ducks/IItemEntity.java

@@ -1,8 +1,8 @@
 package com.minelittlepony.unicopia.ducks;
 
-import com.minelittlepony.unicopia.entity.ItemEntityCapabilities;
+import com.minelittlepony.unicopia.entity.ItemImpl;
 
-public interface IItemEntity extends PonyContainer<ItemEntityCapabilities> {
+public interface IItemEntity extends PonyContainer<ItemImpl> {
 
     int getAge();
 

src/main/java/com/minelittlepony/unicopia/ducks/PonyContainer.java

@@ -10,9 +10,9 @@ import com.minelittlepony.unicopia.magic.Caster;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.LivingEntity;
 
-public interface PonyContainer<T extends Ponylike> {
+public interface PonyContainer<T extends Ponylike<?>> {
 
-    Ponylike create();
+    Ponylike<?> create();
 
     T get();
 
@@ -28,7 +28,7 @@ public interface PonyContainer<T extends Ponylike> {
     }
 
     @SuppressWarnings("unchecked")
-    static <E extends Entity, T extends Ponylike> Optional<PonyContainer<T>> of(Entity entity) {
+    static <E extends Entity, T extends Ponylike<?>> Optional<PonyContainer<T>> of(Entity entity) {
         if (entity instanceof PonyContainer) {
             return Optional.of(((PonyContainer<T>)entity));
         }

src/main/java/com/minelittlepony/unicopia/entity/Creature.java

@@ -15,7 +15,7 @@ import net.minecraft.entity.data.TrackedData;
 import net.minecraft.entity.data.TrackedDataHandlerRegistry;
 import net.minecraft.nbt.CompoundTag;
 
-public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Caster<LivingEntity> {
+public class Creature implements Ponylike<LivingEntity>, Caster<LivingEntity> {
 
     private static final TrackedData<CompoundTag> EFFECT = DataTracker.registerData(LivingEntity.class, TrackedDataHandlerRegistry.TAG_COMPOUND);
 
@@ -23,9 +23,11 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
 
     private final EffectSync effectDelegate = new EffectSync(this, EFFECT);
 
+    private final Physics physics = new EntityPhysics<>(this);
+
     private final LivingEntity entity;
 
-    public LivingEntityCapabilities(LivingEntity entity) {
+    public Creature(LivingEntity entity) {
         this.entity = entity;
 
         entity.getDataTracker().startTracking(EFFECT, new CompoundTag());
@@ -36,6 +38,11 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
         return Race.HUMAN;
     }
 
+    @Override
+    public Physics getPhysics() {
+        return physics;
+    }
+
     @Override
     public void setSpecies(Race race) {
     }
@@ -56,7 +63,7 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
     }
 
     @Override
-    public void onUpdate() {
+    public void tick() {
         if (hasEffect()) {
             AttachedMagicEffect effect = getEffect(AttachedMagicEffect.class, true);
 
@@ -72,11 +79,6 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
         }
     }
 
-    @Override
-    public void onDimensionalTravel(int destinationDimension) {
-
-    }
-
     @Override
     public void setOwner(LivingEntity owner) {
 
@@ -111,6 +113,7 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
         if (effect != null) {
             compound.put("effect", SpellRegistry.instance().serializeEffectToNBT(effect));
         }
+        physics.toNBT(compound);
     }
 
     @Override
@@ -118,5 +121,6 @@ public class LivingEntityCapabilities implements RaceContainer<LivingEntity>, Ca
         if (compound.contains("effect")) {
             setEffect(SpellRegistry.instance().createEffectFromNBT(compound.getCompound("effect")));
         }
+        physics.fromNBT(compound);
     }
 }

src/main/java/com/minelittlepony/unicopia/entity/CuccoonEntity.java

@@ -40,7 +40,7 @@ import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.GameRules;
 import net.minecraft.world.World;
 
-public class CuccoonEntity extends LivingEntity implements IMagicals, InAnimate {
+public class CuccoonEntity extends LivingEntity implements IMagicals, InAnimate, Trap {
 
     private static final TrackedData<Integer> STRUGGLE_COUNT = DataTracker.registerData(CuccoonEntity.class, TrackedDataHandlerRegistry.INTEGER);
 
@@ -206,6 +206,7 @@ public class CuccoonEntity extends LivingEntity implements IMagicals, InAnimate
         return true;
     }
 
+    @Override
     public boolean attemptDismount(Entity captive) {
         if (captive.isSneaking() != captiveLastSneakState) {
             setStruggleCount(getStruggleCount() + 1);

src/main/java/com/minelittlepony/unicopia/entity/EntityPhysics.java

@@ -0,0 +1,101 @@
+package com.minelittlepony.unicopia.entity;
+
+import net.minecraft.block.Block;
+import net.minecraft.block.BlockRenderType;
+import net.minecraft.block.BlockState;
+import net.minecraft.block.FenceGateBlock;
+import net.minecraft.entity.Entity;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.particle.BlockStateParticleEffect;
+import net.minecraft.particle.ParticleTypes;
+import net.minecraft.tag.BlockTags;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.MathHelper;
+import net.minecraft.util.math.Vec3d;
+
+public class EntityPhysics<T extends Ponylike<?> & Owned<? extends Entity>> implements Physics {
+
+    private float gravity = 1;
+
+    protected final T pony;
+
+    public EntityPhysics(T pony) {
+        this.pony = pony;
+    }
+
+    @Override
+    public boolean isFlying() {
+        return false;
+    }
+
+    @Override
+    public double calcGravity(double worldConstant) {
+        return worldConstant * gravity;
+    }
+
+    @Override
+    public BlockPos getHeadPosition() {
+
+        pony.getOwner().onGround = false;
+
+        int i = MathHelper.floor(pony.getOwner().getX());
+        int j = MathHelper.floor(pony.getOwner().getY() + pony.getOwner().getHeight() + 0.20000000298023224D);
+        int k = MathHelper.floor(pony.getOwner().getZ());
+
+        BlockPos blockPos = new BlockPos(i, j, k);
+
+        if (pony.getOwner().world.getBlockState(blockPos).isAir()) {
+            BlockPos blockPos2 = blockPos.down();
+            BlockState blockState = pony.getOwner().world.getBlockState(blockPos2);
+            Block block = blockState.getBlock();
+            if (block.matches(BlockTags.FENCES) || block.matches(BlockTags.WALLS) || block instanceof FenceGateBlock) {
+                pony.getOwner().onGround = true;
+                return blockPos2;
+            }
+        } else {
+            pony.getOwner().onGround = true;
+        }
+
+        return blockPos;
+    }
+
+    @Override
+    public void spawnSprintingParticles() {
+        Entity entity = pony.getOwner();
+        BlockState state = entity.world.getBlockState(getHeadPosition());
+        if (state.getRenderType() != BlockRenderType.INVISIBLE) {
+            Vec3d vel = entity.getVelocity();
+            entity.world.addParticle(new BlockStateParticleEffect(ParticleTypes.BLOCK, state),
+                    entity.getX() + (entity.world.random.nextFloat() - 0.5D) * entity.getWidth(),
+                    entity.getY() + entity.getHeight() - 0.1D,
+                    entity.getZ() + (entity.world.random.nextFloat() - 0.5D) * entity.getWidth(),
+                    vel.x * -4, -1.5D, vel.z * -4);
+        }
+    }
+
+    @Override
+    public void setGravityModifier(float constant) {
+        gravity = constant;
+    }
+
+    @Override
+    public float getGravityModifier() {
+        return gravity;
+    }
+
+    @Override
+    public void toNBT(CompoundTag compound) {
+        if (gravity != 0) {
+            compound.putFloat("gravity", gravity);
+        }
+    }
+
+    @Override
+    public void fromNBT(CompoundTag compound) {
+        if (compound.contains("gravity")) {
+            gravity = compound.getFloat("gravity");
+        } else {
+            gravity = 0;
+        }
+    }
+}

src/main/java/com/minelittlepony/unicopia/entity/ItemImpl.java

@@ -11,19 +11,21 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.util.ActionResult;
 
-public class ItemEntityCapabilities implements RaceContainer<ItemEntity>, Owned<ItemEntity> {
+public class ItemImpl implements Ponylike<ItemEntity>, Owned<ItemEntity> {
     private static final TrackedData<Integer> ITEM_RACE = DataTracker.registerData(ItemEntity.class, TrackedDataHandlerRegistry.INTEGER);
 
     private final ItemEntity owner;
     private Race serverRace;
 
-    public ItemEntityCapabilities(ItemEntity owner) {
+    private final Physics physics = new EntityPhysics<>(this);
+
+    public ItemImpl(ItemEntity owner) {
         this.owner = owner;
         owner.getDataTracker().startTracking(ITEM_RACE, Race.HUMAN.ordinal());
     }
 
     @Override
-    public void onUpdate() {
+    public void tick() {
     }
 
     @Override
@@ -47,6 +49,11 @@ public class ItemEntityCapabilities implements RaceContainer<ItemEntity>, Owned<
         return false;
     }
 
+    @Override
+    public Physics getPhysics() {
+        return physics;
+    }
+
     @Override
     public Race getSpecies() {
         return Race.fromId(getOwner().getDataTracker().get(ITEM_RACE));
@@ -60,12 +67,14 @@ public class ItemEntityCapabilities implements RaceContainer<ItemEntity>, Owned<
     @Override
     public void toNBT(CompoundTag compound) {
         compound.putString("owner_species", getSpecies().name());
+        physics.toNBT(compound);
     }
 
 
     @Override
     public void fromNBT(CompoundTag compound) {
         setSpecies(Race.fromName(compound.getString("owner_species")));
+        physics.fromNBT(compound);
     }
 
     @Override
@@ -73,11 +82,6 @@ public class ItemEntityCapabilities implements RaceContainer<ItemEntity>, Owned<
 
     }
 
-    @Override
-    public void onDimensionalTravel(int destinationDimension) {
-
-    }
-
     @Override
     public ItemEntity getOwner() {
         return owner;

src/main/java/com/minelittlepony/unicopia/entity/Physics.java

@@ -0,0 +1,28 @@
+package com.minelittlepony.unicopia.entity;
+
+import com.minelittlepony.unicopia.util.NbtSerialisable;
+
+import net.minecraft.util.math.BlockPos;
+
+public interface Physics extends NbtSerialisable {
+
+    double calcGravity(double worldConstant);
+
+    float getGravityModifier();
+
+    void setGravityModifier(float constant);
+
+    boolean isFlying();
+
+    BlockPos getHeadPosition();
+
+    void spawnSprintingParticles();
+
+    default boolean isGravityNegative() {
+        return getGravityModifier() < 0;
+    }
+
+    default int getGravitySignum() {
+        return (int)Math.signum(getGravityModifier());
+    }
+}

src/main/java/com/minelittlepony/unicopia/entity/Ponylike.java

@@ -8,13 +8,14 @@ import com.minelittlepony.unicopia.util.NbtSerialisable;
 
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.projectile.ProjectileEntity;
+import net.minecraft.util.Tickable;
 
-public interface Ponylike extends NbtSerialisable, Updatable {
+public interface Ponylike<T extends Entity> extends NbtSerialisable, Tickable {
     Race getSpecies();
 
-    void setSpecies(Race race);
+    Physics getPhysics();
 
-    void onDimensionalTravel(int destinationDimension);
+    void setSpecies(Race race);
 
     /**
      * Returns true if this player is fully invisible.
@@ -54,7 +55,7 @@ public interface Ponylike extends NbtSerialisable, Updatable {
     }
 
     @Nullable
-    static <T extends Ponylike> T of(Entity entity) {
+    static <T extends Ponylike<?>> T of(Entity entity) {
         return PonyContainer.<Entity, T>of(entity)
                 .map(PonyContainer::get)
                 .orElse(null);

src/main/java/com/minelittlepony/unicopia/entity/RaceContainer.java

@@ -1,12 +0,0 @@
-package com.minelittlepony.unicopia.entity;
-
-import net.minecraft.entity.Entity;
-
-/**
- * Generic container for an entity that has a race.
- *
- * @param <T> The type of owner
- */
-public interface RaceContainer<T extends Entity> extends Ponylike {
-
-}

src/main/java/com/minelittlepony/unicopia/entity/Updatable.java

@@ -1,12 +0,0 @@
-package com.minelittlepony.unicopia.entity;
-
-/**
- * Interface for objects that receive regular updates.
- */
-@FunctionalInterface
-public interface Updatable {
-    /**
-     * Called to update the internal logic.
-     */
-    void onUpdate();
-}

src/main/java/com/minelittlepony/unicopia/entity/player/ManaContainer.java

@@ -0,0 +1,32 @@
+package com.minelittlepony.unicopia.entity.player;
+
+public class ManaContainer implements MagicReserves {
+    private final Pony pony;
+
+    public ManaContainer(Pony pony) {
+        this.pony = pony;
+        pony.getOwner().getDataTracker().startTracking(Pony.ENERGY, 0F);
+        pony.getOwner().getDataTracker().startTracking(Pony.EXERTION, 0F);
+    }
+
+    @Override
+    public float getExertion() {
+        return pony.getOwner().getDataTracker().get(Pony.EXERTION);
+    }
+
+    @Override
+    public void setExertion(float exertion) {
+        pony.getOwner().getDataTracker().set(Pony.EXERTION, Math.max(0, exertion));
+    }
+
+    @Override
+    public float getEnergy() {
+        return pony.getOwner().getDataTracker().get(Pony.ENERGY);
+    }
+
+    @Override
+    public void setEnergy(float energy) {
+        pony.getOwner().getDataTracker().set(Pony.ENERGY, Math.max(0, energy));
+    }
+
+}

src/main/java/com/minelittlepony/unicopia/entity/player/Motion.java

@@ -1,9 +1,9 @@
-package com.minelittlepony.unicopia.entity;
+package com.minelittlepony.unicopia.entity.player;
 
 /**
  * Interface for controlling flight.
  */
-public interface FlightControl {
+public interface Motion {
     /**
      * True is we're currently flying.
      */
@@ -14,4 +14,6 @@ public interface FlightControl {
     float getFlightDuration();
 
     boolean isExperienceCritical();
+
+    PlayerDimensions getDimensions();
 }

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerCamera.java

@@ -18,19 +18,19 @@ public class PlayerCamera extends MotionCompositor {
 
         double roll = baseRoll;
 
-        if (player.getFlight().isFlying()) {
+        if (player.getMotion().isFlying()) {
             Vec3d vel = player.getOwner().getVelocity();
 
             roll -= super.calculateRoll(player.getOwner(), vel.x, vel.y, vel.z);
         }
 
-        if (player.getGravity().getGravitationConstant() < 0) {
+        if (player.getPhysics().isGravityNegative()) {
            roll = -roll;
            roll += 180;
         }
 
         if (player.getEntity().age > 10) {
-            roll = player.getInterpolator().interpolate("roll", (float)roll, 250);
+            roll = player.getInterpolator().interpolate("roll", (float)roll, 50);
         }
 
         return (float)roll;
@@ -45,7 +45,7 @@ public class PlayerCamera extends MotionCompositor {
     }
 
     public double calculateFieldOfView(double fov) {
-        fov += player.getMagicalReserves().getExertion() / 5;
+        fov += player.getMagicalReserves().getExertion() / 5F;
         fov += getEnergyAddition();
 
         return fov;

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerDimensions.java

@@ -6,7 +6,7 @@ import com.minelittlepony.unicopia.magic.MagicEffect;
 import net.minecraft.entity.EntityDimensions;
 import net.minecraft.entity.EntityPose;
 
-public final class PlayerDimensionsDelegate {
+public final class PlayerDimensions {
 
     private float defaultEyeHeight;
     private float defaultBodyHeight;
@@ -14,10 +14,13 @@ public final class PlayerDimensionsDelegate {
     private float lastTargetEyeHeight;
     private float lastTargetBodyHeight;
 
-    private final GravityDelegate gravity;
+    private final PlayerPhysics physics;
 
-    public PlayerDimensionsDelegate(GravityDelegate gravity) {
-        this.gravity = gravity;
+    private final Pony pony;
+
+    public PlayerDimensions(Pony pony, PlayerPhysics gravity) {
+        this.pony = pony;
+        this.physics = gravity;
     }
 
     public float getActiveEyeHeight(float original) {
@@ -46,11 +49,11 @@ public final class PlayerDimensionsDelegate {
     private float calculateTargetEyeHeightWithGravity(float targetBodyHeight) {
         float height = calculateTargetEyeHeight();
 
-        if (gravity.getGravitationConstant() < 0 && gravity.player.getOwner().isSneaking()) {
+        if (physics.isGravityNegative() && pony.getOwner().isSneaking()) {
             height += 0.2F;
         }
 
-        if (gravity.getGravitationConstant() < 0) {
+        if (physics.isGravityNegative()) {
             height = targetBodyHeight - height;
         }
 
@@ -58,17 +61,17 @@ public final class PlayerDimensionsDelegate {
     }
 
     private float calculateTargetEyeHeight() {
-        if (gravity.player.hasEffect()) {
-            MagicEffect effect = gravity.player.getEffect();
+        if (pony.hasEffect()) {
+            MagicEffect effect = pony.getEffect();
             if (!effect.isDead() && effect instanceof HeightPredicate) {
-                float val = ((HeightPredicate)effect).getTargetEyeHeight(gravity.player);
+                float val = ((HeightPredicate)effect).getTargetEyeHeight(pony);
                 if (val > 0) {
                     return val;
                 }
             }
         }
 
-        if (gravity.isFlying && gravity.isRainboom()) {
+        if (physics.isFlying && physics.isRainboom()) {
             return 0.5F;
         }
 
@@ -76,17 +79,17 @@ public final class PlayerDimensionsDelegate {
     }
 
     private float calculateTargetBodyHeight() {
-        if (gravity.player.hasEffect()) {
-            MagicEffect effect = gravity.player.getEffect();
+        if (pony.hasEffect()) {
+            MagicEffect effect = pony.getEffect();
             if (!effect.isDead() && effect instanceof HeightPredicate) {
-                float val = ((HeightPredicate)effect).getTargetBodyHeight(gravity.player);
+                float val = ((HeightPredicate)effect).getTargetBodyHeight(pony);
                 if (val > 0) {
                     return val;
                 }
             }
         }
 
-        if (gravity.isFlying && gravity.isRainboom()) {
+        if (physics.isFlying && physics.isRainboom()) {
             return defaultBodyHeight / 2;
         }
 

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerImpl.java

@@ -1,443 +0,0 @@
-package com.minelittlepony.unicopia.entity.player;
-
-import javax.annotation.Nullable;
-
-import com.minelittlepony.unicopia.Race;
-import com.minelittlepony.unicopia.UTags;
-import com.minelittlepony.unicopia.ability.AbilityDispatcher;
-import com.minelittlepony.unicopia.enchanting.PageOwner;
-import com.minelittlepony.unicopia.entity.FlightControl;
-import com.minelittlepony.unicopia.entity.Trap;
-import com.minelittlepony.unicopia.magic.Affinity;
-import com.minelittlepony.unicopia.magic.AttachedMagicEffect;
-import com.minelittlepony.unicopia.magic.HeldMagicEffect;
-import com.minelittlepony.unicopia.magic.MagicEffect;
-import com.minelittlepony.unicopia.magic.MagicalItem;
-import com.minelittlepony.unicopia.magic.spell.SpellRegistry;
-import com.minelittlepony.unicopia.network.Channel;
-import com.minelittlepony.unicopia.network.EffectSync;
-import com.minelittlepony.unicopia.network.MsgPlayerCapabilities;
-import com.minelittlepony.unicopia.toxin.Toxicity;
-import com.minelittlepony.unicopia.toxin.Toxin;
-import com.minelittlepony.util.BasicEasingInterpolator;
-import com.minelittlepony.util.IInterpolator;
-import com.mojang.datafixers.util.Either;
-
-import net.minecraft.client.network.packet.EntityPassengersSetS2CPacket;
-import net.minecraft.entity.Entity;
-import net.minecraft.entity.damage.DamageSource;
-import net.minecraft.entity.data.DataTracker;
-import net.minecraft.entity.data.TrackedData;
-import net.minecraft.entity.data.TrackedDataHandlerRegistry;
-import net.minecraft.entity.player.PlayerEntity;
-import net.minecraft.entity.player.PlayerEntity.SleepFailureReason;
-import net.minecraft.entity.projectile.ProjectileEntity;
-import net.minecraft.item.ItemStack;
-import net.minecraft.nbt.CompoundTag;
-import net.minecraft.server.network.ServerPlayerEntity;
-import net.minecraft.text.TranslatableText;
-import net.minecraft.util.Hand;
-import net.minecraft.util.Unit;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.util.math.Vec3d;
-
-public class PlayerImpl implements Pony, MagicReserves {
-
-    private static final TrackedData<Integer> PLAYER_RACE = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.INTEGER);
-    private static final TrackedData<Float> ENERGY = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.FLOAT);
-    private static final TrackedData<Float> EXERTION = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.FLOAT);
-    private static final TrackedData<CompoundTag> EFFECT = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.TAG_COMPOUND);
-    private static final TrackedData<CompoundTag> HELD_EFFECT = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.TAG_COMPOUND);
-
-    private final PlayerPageStats pageStates = new PlayerPageStats();
-
-    private final AbilityDispatcher powers = new AbilityDispatcher(this);
-
-    private final GravityDelegate gravity = new GravityDelegate(this);
-
-    private final PlayerAttributes attributes = new PlayerAttributes();
-
-    private final PlayerCamera view = new PlayerCamera(this);
-
-    private final PlayerInventory inventory = new PlayerInventory(this);
-
-    private final EffectSync effectDelegate = new EffectSync(this, EFFECT);
-    private final EffectSync heldEffectDelegate = new EffectSync(this, HELD_EFFECT);
-
-    private final IInterpolator interpolator = new BasicEasingInterpolator();
-
-    private float nextStepDistance = 1;
-
-    private final PlayerEntity entity;
-
-    private boolean dirty = false;
-
-    private boolean invisible = false;
-
-    public PlayerImpl(PlayerEntity player) {
-        this.entity = player;
-
-        player.getDataTracker().startTracking(PLAYER_RACE, Race.EARTH.ordinal());
-        player.getDataTracker().startTracking(EXERTION, 0F);
-        player.getDataTracker().startTracking(ENERGY, 0F);
-        player.getDataTracker().startTracking(EFFECT, new CompoundTag());
-        player.getDataTracker().startTracking(HELD_EFFECT, new CompoundTag());
-
-        player.getAttributes().register(PlayerAttributes.EXTENDED_REACH_DISTANCE);
-    }
-
-    @Override
-    public Race getSpecies() {
-        if (getOwner() == null) {
-            return Race.HUMAN;
-        }
-
-        return Race.fromId(getOwner().getDataTracker().get(PLAYER_RACE));
-    }
-
-    @Override
-    public void setSpecies(Race race) {
-        race = race.validate(entity);
-
-        entity.getDataTracker().set(PLAYER_RACE, race.ordinal());
-
-        gravity.updateFlightStat(entity, entity.abilities.flying);
-        entity.sendAbilitiesUpdate();
-    }
-
-    @Override
-    public MagicReserves getMagicalReserves() {
-        return this;
-    }
-
-    @Override
-    public float getExertion() {
-        return getOwner().getDataTracker().get(EXERTION);
-    }
-
-    @Override
-    public void setExertion(float exertion) {
-        entity.getDataTracker().set(EXERTION, Math.max(0, exertion));
-    }
-
-    @Override
-    public float getEnergy() {
-        return entity.getDataTracker().get(ENERGY);
-    }
-
-    @Override
-    public void setEnergy(float energy) {
-        entity.getDataTracker().set(ENERGY, Math.max(0, energy));
-    }
-
-    @Override
-    public boolean isInvisible() {
-        return invisible && hasEffect();
-    }
-
-    @Override
-    public void setInvisible(boolean invisible) {
-        this.invisible = invisible;
-    }
-
-    @Nullable
-    public HeldMagicEffect getHeldEffect(ItemStack stack) {
-
-        if (!getSpecies().canCast()) {
-            heldEffectDelegate.set(null);
-
-            return null;
-        }
-
-        HeldMagicEffect heldEffect = heldEffectDelegate.get(HeldMagicEffect.class, true);
-
-        if (heldEffect == null || !heldEffect.getName().equals(SpellRegistry.getKeyFromStack(stack))) {
-            heldEffect = SpellRegistry.instance().getHeldFrom(stack);
-            heldEffectDelegate.set(heldEffect);
-        }
-
-        return heldEffect;
-    }
-
-    @Override
-    public Affinity getAffinity() {
-        return Affinity.NEUTRAL;
-    }
-
-    @Override
-    public void sendCapabilities(boolean full) {
-        dirty = false;
-
-        if (entity instanceof ServerPlayerEntity) {
-            System.out.println("Sending capabilities for player");
-            Channel.BROADCAST_CAPABILITIES.send(new MsgPlayerCapabilities(full, this));
-        }
-    }
-
-    @Override
-    public void onDimensionalTravel(int destinationDimension) {
-        if (!getWorld().isClient()) {
-            dirty = true;
-        }
-    }
-
-    @Override
-    public AbilityDispatcher getAbilities() {
-        return powers;
-    }
-
-    @Override
-    public PageOwner getPages() {
-        return pageStates;
-    }
-
-    @Override
-    public GravityDelegate getGravity() {
-        return gravity;
-    }
-
-    @Override
-    public float getExtendedReach() {
-        return (float)entity.getAttributeInstance(PlayerAttributes.EXTENDED_REACH_DISTANCE).getValue();
-    }
-
-    @Override
-    public FlightControl getFlight() {
-        return gravity;
-    }
-
-    @Override
-    public PlayerCamera getCamera() {
-        return view;
-    }
-
-    @Override
-    public IInterpolator getInterpolator() {
-        return interpolator;
-    }
-
-    @Override
-    public boolean beforeUpdate() {
-        if (entity.world.isClient()) {
-            if (entity.hasVehicle() && entity.isSneaking()) {
-
-                Entity ridee = entity.getVehicle();
-
-                if (ridee instanceof Trap) {
-                    if (((Trap)ridee).attemptDismount(entity)) {
-                        entity.stopRiding();
-                    } else {
-                        entity.setSneaking(false);
-                    }
-                } else {
-                    entity.stopRiding();
-
-                    if (ridee instanceof ServerPlayerEntity) {
-                        ((ServerPlayerEntity)ridee).networkHandler.sendPacket(new EntityPassengersSetS2CPacket(ridee));
-                    }
-                }
-            }
-        }
-
-        powers.onUpdate();
-        inventory.onUpdate();
-
-        return false;
-    }
-
-    @Override
-    public void onUpdate() {
-        gravity.onUpdate();
-
-        if (hasEffect()) {
-            AttachedMagicEffect effect = getEffect(AttachedMagicEffect.class, true);
-
-            if (effect != null) {
-                if (entity.getEntityWorld().isClient()) {
-                    effect.renderOnPerson(this);
-                }
-
-                if (!effect.updateOnPerson(this)) {
-                    setEffect(null);
-                }
-            }
-        }
-
-        ItemStack stack = entity.getStackInHand(Hand.MAIN_HAND);
-
-        HeldMagicEffect effect = getHeldEffect(stack);
-
-        if (effect != null) {
-            Affinity affinity = stack.getItem() instanceof MagicalItem ? ((MagicalItem)stack.getItem()).getAffinity(stack) : Affinity.NEUTRAL;
-
-            effect.updateInHand(this, affinity);
-        }
-
-        addExertion(-1);
-        addEnergy(-1);
-
-        attributes.applyAttributes(entity, getSpecies());
-
-        if (dirty) {
-            sendCapabilities(true);
-        }
-    }
-
-    @Override
-    public float onImpact(float distance) {
-        if (getSpecies().canFly()) {
-            distance = Math.max(0, distance - 5);
-        }
-        return distance;
-    }
-
-    @Override
-    public void onJump() {
-        if (gravity.getGravitationConstant() < 0) {
-            Vec3d velocity = entity.getVelocity();
-            entity.setVelocity(velocity.x, velocity.y * -1,  velocity.z);
-        }
-    }
-
-    @Override
-    public boolean onProjectileImpact(ProjectileEntity projectile) {
-        if (hasEffect()) {
-            MagicEffect effect = getEffect();
-            if (!effect.isDead() && effect.handleProjectileImpact(projectile)) {
-                return true;
-            }
-        }
-
-        return false;
-    }
-
-    @Override
-    public boolean subtractEnergyCost(double foodSubtract) {
-        if (!entity.abilities.creativeMode) {
-            int food = (int)(entity.getHungerManager().getFoodLevel() - foodSubtract);
-
-            if (food < 0) {
-                entity.getHungerManager().add(-entity.getHungerManager().getFoodLevel(), 0);
-                entity.damage(DamageSource.MAGIC, -food/2);
-            } else {
-                entity.getHungerManager().add((int)-foodSubtract, 0);
-            }
-        }
-
-        return entity.getHealth() > 0;
-    }
-
-    @Override
-    public boolean stepOnCloud() {
-        if (entity.fallDistance > 1 || entity.distanceTraveled > nextStepDistance) {
-            nextStepDistance = entity.distanceTraveled + 2;
-            entity.fallDistance = 0;
-
-            return true;
-        }
-
-        return false;
-    }
-
-    @Override
-    public Either<SleepFailureReason, Unit> trySleep(BlockPos pos) {
-
-        if (getInventory().matches(UTags.CURSED_ARTEFACTS)) {
-            if (!isClient()) {
-                entity.addChatMessage(new TranslatableText("tile.bed.youAreAMonster"), true);
-            }
-            return Either.left(SleepFailureReason.OTHER_PROBLEM);
-        }
-
-        if (findAllSpellsInRange(10).anyMatch(c -> c instanceof Pony && ((Pony)c).getInventory().matches(UTags.CURSED_ARTEFACTS))) {
-            return Either.left(SleepFailureReason.NOT_SAFE);
-        }
-
-        return Either.right(Unit.INSTANCE);
-    }
-
-    @Override
-    public PlayerInventory getInventory() {
-        return inventory;
-    }
-
-    @Override
-    public void onEat(ItemStack stack) {
-        if (getSpecies() == Race.CHANGELING) {
-            Toxin.POISON.afflict(getOwner(), Toxicity.SAFE, stack);
-        }
-    }
-
-    @Override
-    public void toNBT(CompoundTag compound) {
-        compound.putString("playerSpecies", getSpecies().name());
-
-        compound.put("powers", powers.toNBT());
-        compound.put("gravity", gravity.toNBT());
-
-        MagicEffect effect = getEffect();
-
-        if (effect != null) {
-            compound.put("effect", SpellRegistry.instance().serializeEffectToNBT(effect));
-        }
-
-        pageStates.toNBT(compound);
-    }
-
-    @Override
-    public void fromNBT(CompoundTag compound) {
-        setSpecies(Race.fromName(compound.getString("playerSpecies")));
-
-        powers.fromNBT(compound.getCompound("powers"));
-        gravity.fromNBT(compound.getCompound("gravity"));
-
-        if (compound.contains("effect")) {
-            effectDelegate.set(SpellRegistry.instance().createEffectFromNBT(compound.getCompound("effect")));
-        }
-
-        pageStates.fromNBT(compound);
-    }
-
-    @Override
-    public void copyFrom(Pony oldPlayer) {
-        setEffect(oldPlayer.getEffect());
-        setSpecies(oldPlayer.getSpecies());
-        sendCapabilities(true);
-    }
-
-    @Override
-    public void setEffect(@Nullable MagicEffect effect) {
-        effectDelegate.set(effect);
-
-        sendCapabilities(true);
-    }
-
-    @Override
-    public boolean hasEffect() {
-        return effectDelegate.has();
-    }
-
-    @Nullable
-    @Override
-    public <T extends MagicEffect> T getEffect(@Nullable Class<T> type, boolean update) {
-        return effectDelegate.get(type, update);
-    }
-
-    @Override
-    public void setOwner(PlayerEntity owner) {
-    }
-
-    @Override
-    public PlayerEntity getOwner() {
-        return entity;
-    }
-
-    @Override
-    public int getCurrentLevel() {
-        return 0;
-    }
-
-    @Override
-    public void setCurrentLevel(int level) {
-    }
-}

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerInventory.java

@@ -4,7 +4,6 @@ import java.util.Iterator;
 import java.util.Map;
 
 import com.google.common.collect.Maps;
-import com.minelittlepony.unicopia.entity.Updatable;
 import com.minelittlepony.unicopia.item.MagicGemItem;
 import com.minelittlepony.unicopia.magic.AddictiveMagicalItem;
 import com.minelittlepony.unicopia.magic.MagicalItem;
@@ -16,9 +15,10 @@ import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.ListTag;
 import net.minecraft.tag.Tag;
 import net.minecraft.util.Identifier;
+import net.minecraft.util.Tickable;
 import net.minecraft.util.registry.Registry;
 
-public class PlayerInventory implements Updatable, NbtSerialisable {
+public class PlayerInventory implements Tickable, NbtSerialisable {
     private final Map<AddictiveMagicalItem, Entry> dependencies = Maps.newHashMap();
 
     private final Pony player;
@@ -66,7 +66,7 @@ public class PlayerInventory implements Updatable, NbtSerialisable {
     }
 
     @Override
-    public synchronized void onUpdate() {
+    public synchronized void tick() {
 
         Iterator<Map.Entry<AddictiveMagicalItem, Entry>> iterator = dependencies.entrySet().iterator();
 
@@ -75,7 +75,7 @@ public class PlayerInventory implements Updatable, NbtSerialisable {
 
             Entry item = entry.getValue();
 
-            item.onUpdate();
+            item.tick();
 
             if (item.needfulness <= 0.001) {
                 iterator.remove();
@@ -132,7 +132,7 @@ public class PlayerInventory implements Updatable, NbtSerialisable {
         });
     }
 
-    class Entry implements Updatable, NbtSerialisable {
+    class Entry implements Tickable, NbtSerialisable {
         int ticksAttached = 0;
 
         float needfulness = 1;
@@ -152,7 +152,7 @@ public class PlayerInventory implements Updatable, NbtSerialisable {
         }
 
         @Override
-        public void onUpdate() {
+        public void tick() {
             if (isWearing(item)) {
                 ticksAttached ++;
                 needfulness *= 0.9F;

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerPageStats.java

@@ -13,6 +13,12 @@ import net.minecraft.util.Identifier;
 public class PlayerPageStats implements NbtSerialisable, PageOwner {
     private final Map<Identifier, PageState> pageStates = new HashMap<>();
 
+    private final Pony pony;
+
+    PlayerPageStats(Pony pony) {
+        this.pony = pony;
+    }
+
     @Override
     public Map<Identifier, PageState> getPageStates() {
         return pageStates;
@@ -20,7 +26,7 @@ public class PlayerPageStats implements NbtSerialisable, PageOwner {
 
     @Override
     public void sendCapabilities(boolean full) {
-
+        pony.sendCapabilities(full);
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerPhysics.java

@@ -5,8 +5,7 @@ import java.util.Random;
 import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.USounds;
 import com.minelittlepony.unicopia.ability.FlightPredicate;
-import com.minelittlepony.unicopia.entity.FlightControl;
-import com.minelittlepony.unicopia.entity.Updatable;
+import com.minelittlepony.unicopia.entity.EntityPhysics;
 import com.minelittlepony.unicopia.magic.MagicEffect;
 import com.minelittlepony.unicopia.particles.MagicParticleEffect;
 import com.minelittlepony.unicopia.util.NbtSerialisable;
@@ -18,13 +17,12 @@ import net.minecraft.nbt.CompoundTag;
 import net.minecraft.sound.SoundCategory;
 import net.minecraft.sound.SoundEvent;
 import net.minecraft.sound.SoundEvents;
+import net.minecraft.util.Tickable;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.MathHelper;
 import net.minecraft.util.math.Vec3d;
 
-public class GravityDelegate implements Updatable, FlightControl, NbtSerialisable, FlightPredicate {
-
-    final Pony player;
+public class PlayerPhysics extends EntityPhysics<Pony> implements Tickable, Motion, NbtSerialisable {
 
     private static final float MAXIMUM_FLIGHT_EXPERIENCE = 1500;
 
@@ -37,73 +35,63 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
     private double lastTickPosX = 0;
     private double lastTickPosZ = 0;
 
-    private float gravity = 0;
+    private final PlayerDimensions dimensions;
 
-    private final PlayerDimensionsDelegate dimensions;
-
-    public GravityDelegate(Pony player) {
-        this.player = player;
-        this.dimensions = new PlayerDimensionsDelegate(this);
+    public PlayerPhysics(Pony pony) {
+        super(pony);
+        dimensions = new PlayerDimensions(pony, this);
     }
 
-    @Override
-    public boolean checkCanFly(Pony player) {
-        if (player.getOwner().abilities.creativeMode) {
+    private boolean checkCanFly() {
+        if (pony.getOwner().abilities.creativeMode) {
             return true;
         }
 
-        if (player.hasEffect()) {
-            MagicEffect effect = player.getEffect();
+        if (pony.hasEffect()) {
+            MagicEffect effect = pony.getEffect();
             if (!effect.isDead() && effect instanceof FlightPredicate) {
-                return ((FlightPredicate)effect).checkCanFly(player);
+                return ((FlightPredicate)effect).checkCanFly(pony);
             }
         }
 
-        return player.getSpecies().canFly();
+        return pony.getSpecies().canFly();
     }
 
     protected boolean isRainboom() {
-        return Math.sqrt(getHorizontalMotion(player.getOwner())) > 0.4F;
+        return Math.sqrt(getHorizontalMotion(pony.getOwner())) > 0.4F;
     }
 
-    public PlayerDimensionsDelegate getDimensions() {
+    @Override
+    public PlayerDimensions getDimensions() {
         return dimensions;
     }
 
-    public void setGraviationConstant(float constant) {
-        gravity = constant;
-    }
-
-    public float getGravitationConstant() {
-        return gravity;
-    }
-
     @Override
     public boolean isExperienceCritical() {
         return isRainbooming || flightExperience > MAXIMUM_FLIGHT_EXPERIENCE * 0.8;
     }
 
     @Override
-    public void onUpdate() {
-        PlayerEntity entity = player.getOwner();
+    public void tick() {
+        PlayerEntity entity = pony.getOwner();
 
         MutableVector velocity = new MutableVector(entity.getVelocity());
 
-        if (isExperienceCritical() && player.isClient()) {
-            Random rnd = player.getWorld().random;
+        if (isExperienceCritical() && pony.isClient()) {
+            Random rnd = pony.getWorld().random;
 
             for (int i = 0; i < 360 + getHorizontalMotion(entity); i += 10) {
-                Vec3d pos = player.getOriginVector().add(
+                Vec3d pos = pony.getOriginVector().add(
                         rnd.nextGaussian() * entity.getWidth(),
                         rnd.nextGaussian() * entity.getHeight()/2,
                         rnd.nextGaussian() * entity.getWidth()
                 );
 
-                player.addParticle(MagicParticleEffect.UNICORN, pos, velocity.toImmutable());
+                pony.addParticle(MagicParticleEffect.UNICORN, pos, velocity.toImmutable());
             }
         }
 
-        entity.abilities.allowFlying = checkCanFly(player);
+        entity.abilities.allowFlying = checkCanFly();
 
         if (!entity.abilities.creativeMode) {
             entity.abilities.flying |= entity.abilities.allowFlying && isFlying && !entity.onGround && !entity.isTouchingWater();
@@ -111,26 +99,6 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
 
         isFlying = entity.abilities.flying && !entity.abilities.creativeMode;
 
-        if (gravity != 0) {
-            if (!entity.abilities.flying) {
-                velocity.y += 0.038;
-                velocity.y -= gravity;
-            }
-
-            if (gravity < 0) {
-                entity.onGround = !entity.world.isAir(new BlockPos(entity.getX(), entity.getY() + entity.getHeight() + 0.5F, entity.getZ()));
-
-                if (entity.onGround) {
-                    entity.abilities.flying = false;
-                    isFlying = false;
-                }
-            }
-        }
-
-        if (dimensions.update()) {
-            player.getOwner().calculateDimensions();
-        }
-
         if (!entity.abilities.creativeMode && !entity.isFallFlying()) {
             if (isFlying && !entity.hasVehicle()) {
 
@@ -140,7 +108,7 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
 
                 entity.fallDistance = 0;
 
-                if (player.getSpecies() != Race.CHANGELING && entity.world.random.nextInt(100) == 0) {
+                if (pony.getSpecies() != Race.CHANGELING && entity.world.random.nextInt(100) == 0) {
                     float exhaustion = (0.3F * ticksNextLevel) / 70;
                     if (entity.isSprinting()) {
                         exhaustion *= 3.11F;
@@ -163,8 +131,8 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
 
                 if (isExperienceCritical()) {
 
-                    if (player.getMagicalReserves().getEnergy() <= 0.25F) {
-                        player.getMagicalReserves().addEnergy(2);
+                    if (pony.getMagicalReserves().getEnergy() <= 0.25F) {
+                        pony.getMagicalReserves().addEnergy(2);
                     }
 
                     if (isRainbooming || (entity.isSneaking() && isRainboom())) {
@@ -209,6 +177,15 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
             }
         }
 
+        if (pony.getPhysics().isGravityNegative()) {
+            entity.onGround = !entity.world.isAir(new BlockPos(entity.getX(), entity.getY() + entity.getHeight() + 0.5F, entity.getZ()));
+
+            if (entity.onGround) {
+                entity.abilities.flying = false;
+                isFlying = false;
+            }
+        }
+
         lastTickPosX = entity.getX();
         lastTickPosZ = entity.getZ();
 
@@ -216,21 +193,20 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
     }
 
     public SoundEvent getWingSound() {
-        return player.getSpecies() == Race.CHANGELING ? USounds.CHANGELING_BUZZ : USounds.WING_FLAP;
+        return pony.getSpecies() == Race.CHANGELING ? USounds.CHANGELING_BUZZ : USounds.WING_FLAP;
     }
 
     protected void moveFlying(Entity player, MutableVector velocity) {
 
         float forward = 0.000015F * flightExperience * (float)Math.sqrt(getHorizontalMotion(player));
-        int factor = gravity < 0 ? -1 : 1;
         boolean sneak = !player.isSneaking();
 
         // vertical drop due to gravity
         if (sneak) {
-            velocity.y -= (0.005F - getHorizontalMotion(player) / 100) * factor;
+            velocity.y -= (0.005F - getHorizontalMotion(player) / 100) * getGravitySignum();
         } else {
             forward += 0.005F;
-            velocity.y -= 0.0001F * factor;
+            velocity.y -= 0.0001F * getGravitySignum();
         }
 
         velocity.x += - forward * MathHelper.sin(player.yaw * 0.017453292F);
@@ -264,7 +240,6 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
                 forward = 4;
             }
 
-            //player.knockBack(player, forward, 1, 1);
             velocity.x += - forward * MathHelper.sin((player.yaw + glance) * 0.017453292F);
             velocity.z += forward * MathHelper.cos((player.yaw + glance) * 0.017453292F);
         }
@@ -289,8 +264,10 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
         flightExperience = Math.max(0, flightExperience + factor * maximumGain / gainSteps);
     }
 
-    public void updateFlightStat(PlayerEntity entity, boolean flying) {
-        entity.abilities.allowFlying = checkCanFly(Pony.of(entity));
+    public void updateFlightStat(boolean flying) {
+        PlayerEntity entity = pony.getOwner();
+
+        entity.abilities.allowFlying = checkCanFly();
 
         if (entity.abilities.allowFlying) {
             entity.abilities.flying |= flying;
@@ -308,28 +285,22 @@ public class GravityDelegate implements Updatable, FlightControl, NbtSerialisabl
 
     @Override
     public void toNBT(CompoundTag compound) {
+        super.toNBT(compound);
         compound.putInt("flightDuration", ticksNextLevel);
         compound.putFloat("flightExperience", flightExperience);
         compound.putBoolean("isFlying", isFlying);
         compound.putBoolean("isRainbooming", isRainbooming);
-
-        if (gravity != 0) {
-            compound.putFloat("gravity", gravity);
-        }
     }
 
     @Override
     public void fromNBT(CompoundTag compound) {
+        super.fromNBT(compound);
         ticksNextLevel = compound.getInt("flightDuration");
         flightExperience = compound.getFloat("flightExperience");
         isFlying = compound.getBoolean("isFlying");
         isRainbooming = compound.getBoolean("isRainbooming");
 
-        if (compound.contains("gravity")) {
-            gravity = compound.getFloat("gravity");
-        } else {
-            gravity = 0;
-        }
+        pony.getOwner().calculateDimensions();
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/entity/player/Pony.java

@@ -3,111 +3,422 @@ package com.minelittlepony.unicopia.entity.player;
 import javax.annotation.Nullable;
 
 import com.minelittlepony.unicopia.InteractionManager;
+import com.minelittlepony.unicopia.Race;
+import com.minelittlepony.unicopia.UTags;
 import com.minelittlepony.unicopia.ability.AbilityDispatcher;
 import com.minelittlepony.unicopia.ducks.PonyContainer;
 import com.minelittlepony.unicopia.enchanting.PageOwner;
-import com.minelittlepony.unicopia.entity.FlightControl;
-import com.minelittlepony.unicopia.entity.RaceContainer;
+import com.minelittlepony.unicopia.entity.Physics;
+import com.minelittlepony.unicopia.entity.Ponylike;
+import com.minelittlepony.unicopia.entity.Trap;
+import com.minelittlepony.unicopia.magic.Affinity;
+import com.minelittlepony.unicopia.magic.AttachedMagicEffect;
 import com.minelittlepony.unicopia.magic.Caster;
+import com.minelittlepony.unicopia.magic.HeldMagicEffect;
+import com.minelittlepony.unicopia.magic.MagicEffect;
+import com.minelittlepony.unicopia.magic.MagicalItem;
+import com.minelittlepony.unicopia.magic.spell.SpellRegistry;
+import com.minelittlepony.unicopia.network.Channel;
+import com.minelittlepony.unicopia.network.EffectSync;
+import com.minelittlepony.unicopia.network.MsgPlayerCapabilities;
 import com.minelittlepony.unicopia.network.Transmittable;
+import com.minelittlepony.unicopia.toxin.Toxicity;
+import com.minelittlepony.unicopia.toxin.Toxin;
+import com.minelittlepony.util.BasicEasingInterpolator;
 import com.minelittlepony.util.IInterpolator;
 import com.mojang.authlib.GameProfile;
 import com.mojang.datafixers.util.Either;
 
+import net.minecraft.client.network.packet.EntityPassengersSetS2CPacket;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.damage.DamageSource;
+import net.minecraft.entity.data.DataTracker;
+import net.minecraft.entity.data.TrackedData;
+import net.minecraft.entity.data.TrackedDataHandlerRegistry;
 import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.entity.player.PlayerEntity.SleepFailureReason;
+import net.minecraft.entity.projectile.ProjectileEntity;
 import net.minecraft.item.ItemStack;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.text.TranslatableText;
+import net.minecraft.util.Hand;
 import net.minecraft.util.Unit;
 import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Vec3d;
 
-/**
- * The player.
- *
- * This is the core of unicopia.
- */
-public interface Pony extends Caster<PlayerEntity>, RaceContainer<PlayerEntity>, Transmittable {
+public class Pony implements Caster<PlayerEntity>, Ponylike<PlayerEntity>, Transmittable {
 
-    /**
-     * Gets the player's magical abilities delegate responsible for all spell casting and persisting/updating.
-     */
-    AbilityDispatcher getAbilities();
+    private static final TrackedData<Integer> RACE = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.INTEGER);
+    static final TrackedData<Float> ENERGY = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.FLOAT);
+    static final TrackedData<Float> EXERTION = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.FLOAT);
+    private static final TrackedData<CompoundTag> EFFECT = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.TAG_COMPOUND);
+    private static final TrackedData<CompoundTag> HELD_EFFECT = DataTracker.registerData(PlayerEntity.class, TrackedDataHandlerRegistry.TAG_COMPOUND);
 
-    /**
-     * Gets the gravity delegate responsible for updating flight states
-     */
-    GravityDelegate getGravity();
+    private final PlayerPageStats pageStates = new PlayerPageStats(this);
+    private final AbilityDispatcher powers = new AbilityDispatcher(this);
+    private final PlayerPhysics gravity = new PlayerPhysics(this);
+    private final PlayerAttributes attributes = new PlayerAttributes();
+    private final PlayerCamera camera = new PlayerCamera(this);
+    private final PlayerInventory inventory = new PlayerInventory(this);
+    private final MagicReserves mana;
 
-    /**
-     * Gets the flight delegate.
-     */
-    FlightControl getFlight();
+    private final EffectSync effectDelegate = new EffectSync(this, EFFECT);
+    private final EffectSync heldEffectDelegate = new EffectSync(this, HELD_EFFECT);
 
-    /**
-     * Gets the player's viewport.
-     */
-    PlayerCamera getCamera();
+    private final IInterpolator interpolator = new BasicEasingInterpolator();
 
-    MagicReserves getMagicalReserves();
+    private float nextStepDistance = 1;
 
-    /**
-     * Gets the inventory delegate for this player.
-     */
-    PlayerInventory getInventory();
+    private final PlayerEntity entity;
 
-    /**
-     * Gets an animation interpolator.
-     */
-    IInterpolator getInterpolator();
+    private boolean dirty = false;
 
-    PageOwner getPages();
+    private boolean invisible = false;
 
-    /**
-     */
-    float getExtendedReach();
+    public Pony(PlayerEntity player) {
+        this.entity = player;
+        this.mana = new ManaContainer(this);
 
-    void copyFrom(Pony oldPlayer);
+        player.getDataTracker().startTracking(RACE, Race.EARTH.ordinal());
+        player.getDataTracker().startTracking(EFFECT, new CompoundTag());
+        player.getDataTracker().startTracking(HELD_EFFECT, new CompoundTag());
 
-    /**
-     * Called when the player steps on clouds.
-     */
-    boolean stepOnCloud();
+        player.getAttributes().register(PlayerAttributes.EXTENDED_REACH_DISTANCE);
+    }
 
-    /**
-     * Called when this player falls.
-     */
-    float onImpact(float distance);
+    @Override
+    public Race getSpecies() {
+        if (getOwner() == null) {
+            return Race.HUMAN;
+        }
 
-    /**
-     * Called whenever the player eats something.
-     */
-    void onEat(ItemStack food);
+        return Race.fromId(getOwner().getDataTracker().get(RACE));
+    }
 
-    /**
-     * Attempts to sleep in a bed.
-     *
-     * @param pos The position of the bed
-     *
-     * @return The sleep result.
-     */
-    Either<PlayerEntity.SleepFailureReason, Unit> trySleep(BlockPos pos);
+    @Override
+    public void setSpecies(Race race) {
+        race = race.validate(entity);
 
-    /**
-     * Returns true if this player is the use.
-     */
-    default boolean isClientPlayer() {
+        entity.getDataTracker().set(RACE, race.ordinal());
+
+        gravity.updateFlightStat(entity.abilities.flying);
+        entity.sendAbilitiesUpdate();
+    }
+
+    public MagicReserves getMagicalReserves() {
+        return mana;
+    }
+
+    @Override
+    public boolean isInvisible() {
+        return invisible && hasEffect();
+    }
+
+    @Override
+    public void setInvisible(boolean invisible) {
+        this.invisible = invisible;
+    }
+
+    @Nullable
+    public HeldMagicEffect getHeldEffect(ItemStack stack) {
+
+        if (!getSpecies().canCast()) {
+            heldEffectDelegate.set(null);
+            return null;
+        }
+
+        HeldMagicEffect heldEffect = heldEffectDelegate.get(HeldMagicEffect.class, true);
+
+        if (heldEffect == null || !heldEffect.getName().equals(SpellRegistry.getKeyFromStack(stack))) {
+            heldEffect = SpellRegistry.instance().getHeldFrom(stack);
+            heldEffectDelegate.set(heldEffect);
+        }
+
+        return heldEffect;
+    }
+
+    @Override
+    public Affinity getAffinity() {
+        return Affinity.NEUTRAL;
+    }
+
+    public void setDirty() {
+        dirty = true;
+    }
+
+    @Override
+    public void sendCapabilities(boolean full) {
+        dirty = false;
+
+        if (entity instanceof ServerPlayerEntity) {
+            System.out.println("Sending capabilities for player");
+            Channel.BROADCAST_CAPABILITIES.send(new MsgPlayerCapabilities(full, this));
+        }
+    }
+
+    public AbilityDispatcher getAbilities() {
+        return powers;
+    }
+
+    public PageOwner getPages() {
+        return pageStates;
+    }
+
+    @Override
+    public Physics getPhysics() {
+        return gravity;
+    }
+
+    public float getExtendedReach() {
+        return (float)entity.getAttributeInstance(PlayerAttributes.EXTENDED_REACH_DISTANCE).getValue();
+    }
+
+    public Motion getMotion() {
+        return gravity;
+    }
+
+    public PlayerCamera getCamera() {
+        return camera;
+    }
+
+    public IInterpolator getInterpolator() {
+        return interpolator;
+    }
+
+    @Override
+    public boolean beforeUpdate() {
+        if (entity.world.isClient()) {
+            if (entity.hasVehicle() && entity.isSneaking()) {
+
+                Entity ridee = entity.getVehicle();
+
+                if (ridee instanceof Trap) {
+                    if (((Trap)ridee).attemptDismount(entity)) {
+                        entity.stopRiding();
+                    } else {
+                        entity.setSneaking(false);
+                    }
+                } else {
+                    entity.stopRiding();
+
+                    if (ridee instanceof ServerPlayerEntity) {
+                        ((ServerPlayerEntity)ridee).networkHandler.sendPacket(new EntityPassengersSetS2CPacket(ridee));
+                    }
+                }
+            }
+        }
+
+        powers.tick();
+        inventory.tick();
+
+        return false;
+    }
+
+    @Override
+    public void tick() {
+        gravity.tick();
+
+        if (hasEffect()) {
+            AttachedMagicEffect effect = getEffect(AttachedMagicEffect.class, true);
+
+            if (effect != null) {
+                if (entity.getEntityWorld().isClient()) {
+                    effect.renderOnPerson(this);
+                }
+
+                if (!effect.updateOnPerson(this)) {
+                    setEffect(null);
+                }
+            }
+        }
+
+        ItemStack stack = entity.getStackInHand(Hand.MAIN_HAND);
+
+        HeldMagicEffect effect = getHeldEffect(stack);
+
+        if (effect != null) {
+            Affinity affinity = stack.getItem() instanceof MagicalItem ? ((MagicalItem)stack.getItem()).getAffinity(stack) : Affinity.NEUTRAL;
+
+            effect.updateInHand(this, affinity);
+        }
+
+        mana.addExertion(-1);
+        mana.addEnergy(-1);
+
+        attributes.applyAttributes(entity, getSpecies());
+
+        if (dirty) {
+            sendCapabilities(true);
+        }
+    }
+
+    public float onImpact(float distance) {
+        if (getSpecies().canFly()) {
+            distance = Math.max(0, distance - 5);
+        }
+        return distance;
+    }
+
+    @Override
+    public void onJump() {
+        if (gravity.isGravityNegative()) {
+            Vec3d velocity = entity.getVelocity();
+            entity.setVelocity(velocity.x, velocity.y * -1,  velocity.z);
+        }
+    }
+
+    @Override
+    public boolean onProjectileImpact(ProjectileEntity projectile) {
+        if (hasEffect()) {
+            MagicEffect effect = getEffect();
+            if (!effect.isDead() && effect.handleProjectileImpact(projectile)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public boolean subtractEnergyCost(double foodSubtract) {
+        if (!entity.abilities.creativeMode) {
+            int food = (int)(entity.getHungerManager().getFoodLevel() - foodSubtract);
+
+            if (food < 0) {
+                entity.getHungerManager().add(-entity.getHungerManager().getFoodLevel(), 0);
+                entity.damage(DamageSource.MAGIC, -food/2);
+            } else {
+                entity.getHungerManager().add((int)-foodSubtract, 0);
+            }
+        }
+
+        return entity.getHealth() > 0;
+    }
+
+    public boolean stepOnCloud() {
+        if (entity.fallDistance > 1 || entity.distanceTraveled > nextStepDistance) {
+            nextStepDistance = entity.distanceTraveled + 2;
+            entity.fallDistance = 0;
+
+            return true;
+        }
+
+        return false;
+    }
+
+    public Either<SleepFailureReason, Unit> trySleep(BlockPos pos) {
+
+        if (getInventory().matches(UTags.CURSED_ARTEFACTS)) {
+            if (!isClient()) {
+                entity.addChatMessage(new TranslatableText("tile.bed.youAreAMonster"), true);
+            }
+            return Either.left(SleepFailureReason.OTHER_PROBLEM);
+        }
+
+        if (findAllSpellsInRange(10).anyMatch(c -> c instanceof Pony && ((Pony)c).getInventory().matches(UTags.CURSED_ARTEFACTS))) {
+            return Either.left(SleepFailureReason.NOT_SAFE);
+        }
+
+        return Either.right(Unit.INSTANCE);
+    }
+
+    public PlayerInventory getInventory() {
+        return inventory;
+    }
+
+    public void onEat(ItemStack stack) {
+        if (getSpecies() == Race.CHANGELING) {
+            Toxin.POISON.afflict(getOwner(), Toxicity.SAFE, stack);
+        }
+    }
+
+    @Override
+    public void toNBT(CompoundTag compound) {
+        compound.putString("playerSpecies", getSpecies().name());
+
+        compound.put("powers", powers.toNBT());
+        compound.put("gravity", gravity.toNBT());
+
+        MagicEffect effect = getEffect();
+
+        if (effect != null) {
+            compound.put("effect", SpellRegistry.instance().serializeEffectToNBT(effect));
+        }
+
+        pageStates.toNBT(compound);
+    }
+
+    @Override
+    public void fromNBT(CompoundTag compound) {
+        setSpecies(Race.fromName(compound.getString("playerSpecies")));
+
+        powers.fromNBT(compound.getCompound("powers"));
+        gravity.fromNBT(compound.getCompound("gravity"));
+
+        if (compound.contains("effect")) {
+            effectDelegate.set(SpellRegistry.instance().createEffectFromNBT(compound.getCompound("effect")));
+        }
+
+        pageStates.fromNBT(compound);
+    }
+
+    public void copyFrom(Pony oldPlayer) {
+        setEffect(oldPlayer.getEffect());
+        setSpecies(oldPlayer.getSpecies());
+        setDirty();
+    }
+
+    @Override
+    public void setEffect(@Nullable MagicEffect effect) {
+        effectDelegate.set(effect);
+        setDirty();
+    }
+
+    @Override
+    public boolean hasEffect() {
+        return effectDelegate.has();
+    }
+
+    @Nullable
+    @Override
+    public <T extends MagicEffect> T getEffect(@Nullable Class<T> type, boolean update) {
+        return effectDelegate.get(type, update);
+    }
+
+    @Override
+    public void setOwner(PlayerEntity owner) {
+    }
+
+    @Override
+    public PlayerEntity getOwner() {
+        return entity;
+    }
+
+    @Override
+    public int getCurrentLevel() {
+        return 0;
+    }
+
+    @Override
+    public void setCurrentLevel(int level) {
+    }
+
+    public boolean isClientPlayer() {
         return InteractionManager.instance().isClientPlayer(getOwner());
     }
 
     @SuppressWarnings("unchecked")
     @Nullable
-    static Pony of(@Nullable PlayerEntity player) {
+    public static Pony of(@Nullable PlayerEntity player) {
         return player == null ? null : ((PonyContainer<Pony>)player).get();
     }
 
-    static boolean equal(GameProfile one, GameProfile two) {
+    public static boolean equal(GameProfile one, GameProfile two) {
         return one == two || (one != null && two != null && one.getId().equals(two.getId()));
     }
 
-    static boolean equal(PlayerEntity one, PlayerEntity two) {
+    public static boolean equal(PlayerEntity one, PlayerEntity two) {
         return one == two || (one != null && two != null && equal(one.getGameProfile(), two.getGameProfile()));
     }
 }

src/main/java/com/minelittlepony/unicopia/item/AlicornAmuletItem.java

@@ -8,7 +8,7 @@ import javax.annotation.Nullable;
 import com.google.common.collect.Multimap;
 import com.minelittlepony.unicopia.AwaitTickQueue;
 import com.minelittlepony.unicopia.ducks.IItemEntity;
-import com.minelittlepony.unicopia.entity.ItemEntityCapabilities;
+import com.minelittlepony.unicopia.entity.ItemImpl;
 import com.minelittlepony.unicopia.entity.player.MagicReserves;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.magic.Affinity;
@@ -48,7 +48,7 @@ import net.minecraft.world.LocalDifficulty;
 import net.minecraft.world.World;
 import net.minecraft.world.explosion.Explosion.DestructionType;
 
-public class AlicornAmuletItem extends ArmorItem implements AddictiveMagicalItem, ItemEntityCapabilities.TickableItem {
+public class AlicornAmuletItem extends ArmorItem implements AddictiveMagicalItem, ItemImpl.TickableItem {
 
     private static final UUID[] MODIFIERS = new UUID[] {
             UUID.fromString("845DB27C-C624-495F-8C9F-6020A9A58B6B"),

src/main/java/com/minelittlepony/unicopia/item/AppleItem.java

@@ -4,7 +4,7 @@ import java.util.List;
 import javax.annotation.Nullable;
 
 import com.minelittlepony.unicopia.ducks.IItemEntity;
-import com.minelittlepony.unicopia.entity.ItemEntityCapabilities;
+import com.minelittlepony.unicopia.entity.ItemImpl;
 import com.minelittlepony.unicopia.toxin.Toxicity;
 import net.minecraft.client.item.TooltipContext;
 import net.minecraft.entity.EntityType;
@@ -17,7 +17,7 @@ import net.minecraft.util.ActionResult;
 import net.minecraft.util.math.MathHelper;
 import net.minecraft.world.World;
 
-public class AppleItem extends Item implements ItemEntityCapabilities.TickableItem {
+public class AppleItem extends Item implements ItemImpl.TickableItem {
 
     public AppleItem(Settings settings) {
         super(settings);

src/main/java/com/minelittlepony/unicopia/magic/Useable.java

@@ -19,7 +19,7 @@ public interface Useable {
      *
      * @param stack        The current itemstack
      * @param affinity  The affinity of the casting artifact
-     * @param player    The player
+     * @param pony    The player
      * @param world        The player's world
      * @param pos        The location clicked
      * @param side        The side of the block clicked

src/main/java/com/minelittlepony/unicopia/mixin/MixinItemEntity.java

@@ -7,7 +7,7 @@ import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
 import com.minelittlepony.unicopia.ducks.IItemEntity;
-import com.minelittlepony.unicopia.entity.ItemEntityCapabilities;
+import com.minelittlepony.unicopia.entity.ItemImpl;
 
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.ItemEntity;
@@ -16,17 +16,17 @@ import net.minecraft.nbt.CompoundTag;
 @Mixin(ItemEntity.class)
 abstract class MixinItemEntity extends Entity implements IItemEntity {
 
-    private ItemEntityCapabilities caster;
+    private ItemImpl caster;
 
     private MixinItemEntity() { super(null, null); }
 
     @Override
-    public ItemEntityCapabilities create() {
-        return new ItemEntityCapabilities((ItemEntity)(Object)this);
+    public ItemImpl create() {
+        return new ItemImpl((ItemEntity)(Object)this);
     }
 
     @Override
-    public ItemEntityCapabilities get() {
+    public ItemImpl get() {
         if (caster == null) {
             caster = create();
         }
@@ -42,7 +42,7 @@ abstract class MixinItemEntity extends Entity implements IItemEntity {
 
     @Inject(method = "tick()V", at = @At("RETURN"))
     private void afterTick(CallbackInfo info) {
-        get().onUpdate();
+        get().tick();
     }
 
     @Inject(method = "writeCustomDataToTag(Lnet/minecraft/nbt/CompoundTag;)V", at = @At("HEAD"))

src/main/java/com/minelittlepony/unicopia/mixin/MixinLivingEntity.java

@@ -2,32 +2,35 @@ package com.minelittlepony.unicopia.mixin;
 
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Constant;
 import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.ModifyConstant;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 import com.minelittlepony.unicopia.ducks.PonyContainer;
 import com.minelittlepony.unicopia.entity.Ponylike;
-import com.minelittlepony.unicopia.entity.LivingEntityCapabilities;
+import com.minelittlepony.unicopia.entity.Creature;
 
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.nbt.CompoundTag;
+import net.minecraft.util.math.BlockPos;
 
 @Mixin(LivingEntity.class)
-abstract class MixinLivingEntity extends Entity implements PonyContainer<Ponylike> {
+abstract class MixinLivingEntity extends Entity implements PonyContainer<Ponylike<?>> {
 
-    private Ponylike caster;
+    private Ponylike<?> caster;
 
     private MixinLivingEntity() { super(null, null); }
 
     @Override
-    public Ponylike create() {
-        return new LivingEntityCapabilities((LivingEntity)(Object)this);
+    public Ponylike<?> create() {
+        return new Creature((LivingEntity)(Object)this);
     }
 
     @Override
-    public Ponylike get() {
+    public Ponylike<?> get() {
         if (caster == null) {
             caster = create();
         }
@@ -55,12 +58,12 @@ abstract class MixinLivingEntity extends Entity implements PonyContainer<Ponylik
 
     @Inject(method = "tick()V", at = @At("RETURN"))
     private void afterTick(CallbackInfo info) {
-        get().onUpdate();
+        get().tick();
     }
 
     @Inject(method = "<clinit>()V", at = @At("RETURN"), remap = false)
     private static void clinit(CallbackInfo info) {
-        LivingEntityCapabilities.boostrap();
+        Creature.boostrap();
     }
 
     @Inject(method = "writeCustomDataToTag(Lnet/minecraft/nbt/CompoundTag;)V", at = @At("HEAD"))
@@ -75,6 +78,31 @@ abstract class MixinLivingEntity extends Entity implements PonyContainer<Ponylik
         }
     }
 
+    @ModifyConstant(method = "travel(Lnet/minecraft/util/math/Vec3d;)V", constant = {
+            @Constant(doubleValue = 0.08D),
+            @Constant(doubleValue = 0.01D)
+    })
+    private double modifyGravity(double initial) {
+        return get().getPhysics().calcGravity(initial);
+    }
+
+    @Override
+    protected BlockPos getLandingPos() {
+        if (get().getPhysics().isGravityNegative()) {
+            return get().getPhysics().getHeadPosition();
+        }
+        return super.getLandingPos();
+    }
+
+    @Override
+    protected void spawnSprintingParticles() {
+        if (get().getPhysics().isGravityNegative()) {
+            get().getPhysics().spawnSprintingParticles();
+        } else {
+            super.spawnSprintingParticles();
+        }
+    }
+
     // ---------- temporary
     @SuppressWarnings("deprecation")
     @Inject(method = "isClimbing()Z", at = @At("HEAD"), cancellable = true)

src/main/java/com/minelittlepony/unicopia/mixin/MixinPlayerEntity.java

@@ -10,7 +10,6 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 import com.minelittlepony.unicopia.ducks.PonyContainer;
 import com.minelittlepony.unicopia.entity.Ponylike;
 import com.minelittlepony.unicopia.entity.player.Pony;
-import com.minelittlepony.unicopia.entity.player.PlayerImpl;
 import com.mojang.datafixers.util.Either;
 
 import net.minecraft.entity.EntityDimensions;
@@ -29,8 +28,8 @@ abstract class MixinPlayerEntity extends LivingEntity implements PonyContainer<P
     private MixinPlayerEntity() { super(null, null); }
 
     @Override
-    public Ponylike create() {
-        return new PlayerImpl((PlayerEntity)(Object)this);
+    public Ponylike<?> create() {
+        return new Pony((PlayerEntity)(Object)this);
     }
 
     @ModifyVariable(method = "handleFallDamage(FF)Z",
@@ -72,20 +71,20 @@ abstract class MixinPlayerEntity extends LivingEntity implements PonyContainer<P
             at = @At("RETURN"))
     private void onSetGameMode(GameMode mode, CallbackInfo info) {
         get().setSpecies(get().getSpecies());
-        get().sendCapabilities(true);
+        get().setDirty();
     }
 
     @Inject(method = "getActiveEyeHeight(Lnet/minecraft/entity/EntityPose;Lnet/minecraft/entity/EntityDimensions;)F",
             at = @At("RETURN"),
             cancellable = true)
     private void onGetActiveEyeHeight(EntityPose pose, EntityDimensions dimensions, CallbackInfoReturnable<Float> info) {
-        info.setReturnValue(get().getGravity().getDimensions().getActiveEyeHeight(info.getReturnValue()));
+        info.setReturnValue(get().getMotion().getDimensions().getActiveEyeHeight(info.getReturnValue()));
     }
 
     @Inject(method = "getDimensions(Lnet/minecraft/entity/EntityPose;)Lnet/minecraft/entity/EntityDimensions;",
             at = @At("RETURN"),
             cancellable = true)
     public void onGetDimensions(EntityPose pose, CallbackInfoReturnable<EntityDimensions> info) {
-        info.setReturnValue(get().getGravity().getDimensions().getDimensions(pose, info.getReturnValue()));
+        info.setReturnValue(get().getMotion().getDimensions().getDimensions(pose, info.getReturnValue()));
     }
 }

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinCamera.java

@@ -2,15 +2,11 @@ package com.minelittlepony.unicopia.mixin.client;
 
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.At.Shift;
-import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.ModifyVariable;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
 import com.minelittlepony.unicopia.entity.player.Pony;
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.render.Camera;
-import net.minecraft.client.util.math.Vector3f;
 import net.minecraft.entity.player.PlayerEntity;
 
 @Mixin(Camera.class)
@@ -42,18 +38,4 @@ abstract class MixinCamera {
 
         return pitch;
     }
-
-    @Inject(method = "setRotation(FF)V",
-            at = @At(value = "INVOKE",
-                target = "Lnet/minecraft/util/math/Quaternion;set(FFFF)V",
-                shift = Shift.AFTER)
-    )
-    private void onSetRotation(float yaw, float pitch, CallbackInfo info) {
-        PlayerEntity player = MinecraftClient.getInstance().player;
-
-        if (player != null && MinecraftClient.getInstance().cameraEntity == player) {
-            float roll = Pony.of(player).getCamera().calculateRoll();
-            ((Camera)(Object)this).getRotation().hamiltonProduct(Vector3f.POSITIVE_Z.getDegreesQuaternion(roll));
-        }
-    }
 }

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinEntityRenderDispatcher.java

@@ -5,6 +5,7 @@ import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
+import com.minelittlepony.unicopia.client.render.WorldRenderDelegate;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.magic.spell.DisguiseSpell;
 
@@ -31,13 +32,7 @@ abstract class MixinEntityRenderDispatcher {
 
         Pony pony = Pony.of((PlayerEntity)entity);
 
-        if (pony.getGravity().getGravitationConstant() < 0) {
-            matrices.push();
-            matrices.translate(0, entity.getDimensions(entity.getPose()).height, 0);
-            matrices.scale(1, -1, 1);
-            entity.prevPitch *= -1;
-            entity.pitch *= -1;
-        }
+        WorldRenderDelegate.INSTANCE.beforeEntityRender(pony, matrices, x, y, z);
 
         DisguiseSpell effect = pony.getEffect(DisguiseSpell.class, true);
 
@@ -64,19 +59,13 @@ abstract class MixinEntityRenderDispatcher {
         }
     }
 
-    @Inject(method = RENDER, at = @At("HEAD"))
+    @Inject(method = RENDER, at = @At("RETURN"))
     private <E extends Entity> void afterRender(E entity, double x, double y, double z, float yaw, float tickDelta, MatrixStack matrices, VertexConsumerProvider vertexConsumers, int light, CallbackInfo info) {
 
         if (!(entity instanceof PlayerEntity)) {
             return;
         }
 
-        Pony pony = Pony.of((PlayerEntity)entity);
-
-        if (pony.getGravity().getGravitationConstant() < 0) {
-            matrices.pop();
-            entity.prevPitch *= -1;
-            entity.pitch *= -1;
-        }
+        WorldRenderDelegate.INSTANCE.afterEntityRender(Pony.of((PlayerEntity)entity), matrices);
     }
 }

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinGameRenderer.java

@@ -3,13 +3,16 @@ package com.minelittlepony.unicopia.mixin.client;
 import org.spongepowered.asm.mixin.Mixin;
 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 com.minelittlepony.unicopia.client.render.WorldRenderDelegate;
 import com.minelittlepony.unicopia.entity.player.Pony;
 
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.render.Camera;
 import net.minecraft.client.render.GameRenderer;
+import net.minecraft.client.util.math.MatrixStack;
 import net.minecraft.resource.SynchronousResourceReloadListener;
 
 @Mixin(GameRenderer.class)
@@ -22,4 +25,10 @@ abstract class MixinGameRenderer implements AutoCloseable, SynchronousResourceRe
                 .getCamera()
                 .calculateFieldOfView(info.getReturnValue()));
     }
+
+    @Inject(method = "renderWorld(FLLnet/minecraft/client/util/math/MatrixStack;)V",
+            at = @At("HEAD"))
+    public void onRenderWorld(float tickDelta, long limitTime, MatrixStack matrices, CallbackInfo info) {
+        WorldRenderDelegate.INSTANCE.applyWorldTransform(matrices, tickDelta);
+    }
 }

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinKeyboardInput.java

@@ -17,7 +17,7 @@ abstract class MixinKeyboardInput extends Input {
     private void onTick(boolean strafe, CallbackInfo info) {
         Pony player = Pony.of(MinecraftClient.getInstance().player);
 
-        if (player.getGravity().getGravitationConstant() < 0) {
+        if (player.getPhysics().isGravityNegative()) {
             boolean tmp = pressingLeft;
 
             pressingLeft = pressingRight;

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinMouse.java

@@ -21,7 +21,7 @@ abstract class MixinMouse {
     @Inject(method = "updateMouse()V", at = @At("HEAD"))
     private void onUpdateMouse(CallbackInfo info) {
         Pony player = Pony.of(MinecraftClient.getInstance().player);
-        if (player != null&& player.getGravity().getGravitationConstant() < 0) {
+        if (player != null&& player.getPhysics().isGravityNegative()) {
             cursorDeltaX = -cursorDeltaX;
             cursorDeltaY = -cursorDeltaY;
         }