Send a velocity update to the client when modifying player velocities. (should fix some instances of knockback not working when it should)

i.e.
When wearing the alicorn amulet,
When hit by a jar,
When hit by a polearm
When hit by an earth pony stomp
When kicked by an earth pony
When screeched at by a bat pony

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

@@ -7,6 +7,7 @@ import com.minelittlepony.unicopia.USounds;
 import com.minelittlepony.unicopia.ability.data.Hit;
 import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
 import com.minelittlepony.unicopia.advancement.UCriteria;
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.util.MagicalDamageSource;
 
@@ -79,15 +80,16 @@ public class BatEeeeAbility implements Ability<Hit> {
         }
 
         int total = player.findAllEntitiesInRange(5).mapToInt(e -> {
-            if (e instanceof LivingEntity && !SpellType.SHIELD.isOn(e)) {
+            if (e instanceof LivingEntity living && !SpellType.SHIELD.isOn(e)) {
                 boolean isEarthPony = EquinePredicates.PLAYER_EARTH.test(e);
                 e.damage(MagicalDamageSource.create("eeee", player).setBreakSunglasses(), isEarthPony ? 0.1F : 0.3F);
 
                 Vec3d knockVec = origin.subtract(e.getPos());
-                ((LivingEntity) e).takeKnockback(isEarthPony ? 0.3F : 0.5F, knockVec.getX(), knockVec.getZ());
+                living.takeKnockback(isEarthPony ? 0.3F : 0.5F, knockVec.getX(), knockVec.getZ());
                 if (!isEarthPony) {
                     e.addVelocity(0, 0.1, 0);
                 }
+                Living.updateVelocity(e);
             }
             return 1;
         }).sum();

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

@@ -12,6 +12,7 @@ import com.minelittlepony.unicopia.ability.data.tree.TreeType;
 import com.minelittlepony.unicopia.block.data.BlockDestructionManager;
 import com.minelittlepony.unicopia.client.minelittlepony.MineLPDelegate;
 import com.minelittlepony.unicopia.client.render.PlayerPoser.Animation;
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.particle.ParticleUtils;
 import com.minelittlepony.unicopia.particle.UParticles;
@@ -84,6 +85,7 @@ public class EarthPonyKickAbility implements Ability<Pos> {
                             float calculatedStrength = 0.5F * (1 + player.getLevel().getScaled(9));
                             entity.damage(MagicalDamageSource.KICK, player.getReferenceWorld().random.nextBetween(2, 10) + calculatedStrength);
                             entity.takeKnockback(calculatedStrength, origin.x - entity.getX(), origin.z - entity.getZ());
+                            Living.updateVelocity(entity);
                             player.subtractEnergyCost(3);
                             player.setAnimation(Animation.KICK);
                             return;

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

@@ -6,6 +6,7 @@ import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.data.Hit;
 import com.minelittlepony.unicopia.block.data.BlockDestructionManager;
 import com.minelittlepony.unicopia.client.render.PlayerPoser.Animation;
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.item.UItems;
 import com.minelittlepony.unicopia.item.enchantment.UEnchantments;
@@ -85,6 +86,7 @@ public class EarthPonyStompAbility implements Ability<Hit> {
 
         double downV = Math.sqrt(ppos.getSquaredDistance(pos)) * player.getPhysics().getGravitySignum();
         player.getMaster().addVelocity(0, -downV, 0);
+        player.updateVelocity();
     }
 
     @Override
@@ -138,6 +140,7 @@ public class EarthPonyStompAbility implements Ability<Hit> {
                     }
 
                     i.damage(damage, (float)amount);
+                    Living.updateVelocity(i);
                 }
             });
 

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

@@ -2,8 +2,7 @@ package com.minelittlepony.unicopia.ability;
 
 import org.jetbrains.annotations.Nullable;
 
-import com.minelittlepony.unicopia.Race;
+import com.minelittlepony.unicopia.*;
-import com.minelittlepony.unicopia.USounds;
 import com.minelittlepony.unicopia.ability.data.Hit;
 import com.minelittlepony.unicopia.ability.magic.spell.HomingSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.Spell;

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/AttractionUtils.java

@@ -1,5 +1,6 @@
 package com.minelittlepony.unicopia.ability.magic.spell.effect;
 
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.item.enchantment.UEnchantments;
 
@@ -37,6 +38,7 @@ public interface AttractionUtils {
                 center.y + yChange,
                 center.z
         );
+        Living.updateVelocity(target);
     }
 
     /**

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

@@ -148,6 +148,8 @@ public class AirBalloonEntity extends FlyingEntity implements EntityCollisions.C
                 e.setVelocity(vel.getX(), yVel, vel.getZ());
                 e.setVelocity(e.getVelocity().multiply(0.3).add(getVelocity().multiply(0.786)));
                 e.setOnGround(true);
+
+                Living.updateVelocity(e);
             }
         }
 
@@ -163,6 +165,7 @@ public class AirBalloonEntity extends FlyingEntity implements EntityCollisions.C
 
     @Override
     public void onPlayerCollision(PlayerEntity player) {
+        // TODO: check that this is still working correctly after adding Living.updateVelocity(i) in AirBalloonEntity.tick()
         if (getVelocity().lengthSquared() > 0) {
            // player.setVelocity(getVelocity().multiply(1.3));
             player.setVelocity(player.getVelocity().multiply(0.3).add(getVelocity().multiply(
@@ -174,6 +177,8 @@ public class AirBalloonEntity extends FlyingEntity implements EntityCollisions.C
             if (diff > 0) {
                 player.addVelocity(0, diff, 0);
             }
+
+            Living.updateVelocity(player);
         }
     }
 

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

@@ -9,8 +9,7 @@ import org.jetbrains.annotations.Nullable;
 import com.minelittlepony.unicopia.Affinity;
 import com.minelittlepony.unicopia.AwaitTickQueue;
 import com.minelittlepony.unicopia.USounds;
-import com.minelittlepony.unicopia.entity.IItemEntity;
+import com.minelittlepony.unicopia.entity.*;
-import com.minelittlepony.unicopia.entity.ItemImpl;
 import com.minelittlepony.unicopia.entity.effect.UEffects;
 import com.minelittlepony.unicopia.entity.player.MagicReserves;
 import com.minelittlepony.unicopia.entity.player.PlayerCharmTracker;
@@ -133,6 +132,7 @@ public class AlicornAmuletItem extends AmuletItem implements PlayerCharmTracker.
 
         if (attachedTime > 120) {
             pony.getMaster().takeKnockback(1, 1, 1);
+            pony.updateVelocity();
         }
     }
 

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

@@ -1,6 +1,7 @@
 package com.minelittlepony.unicopia.item;
 
 import com.minelittlepony.unicopia.entity.IItemEntity;
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
 
 import net.minecraft.block.Block;
@@ -89,12 +90,13 @@ public class FilledJarItem extends JarItem implements ChameleonItem {
 
             final float toRadians = (float)Math.PI / 180F;
 
-            if (entity instanceof LivingEntity) {
+            if (entity instanceof LivingEntity living) {
-                ((LivingEntity)entity).takeKnockback(
+                living.takeKnockback(
                         knockback / 2F,
                         MathHelper.sin(projectile.getYaw() * toRadians),
                        -MathHelper.cos(projectile.getYaw() * toRadians)
                );
+                Living.updateVelocity(living);
 
                 if (fire > 0) {
                     entity.setOnFireFor(fire * 4);

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

@@ -5,6 +5,7 @@ import java.util.UUID;
 import com.google.common.collect.ImmutableMultimap;
 import com.google.common.collect.Multimap;
 import com.minelittlepony.unicopia.UTags;
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.UEntityAttributes;
 
 import net.minecraft.block.*;
@@ -12,8 +13,6 @@ import net.minecraft.entity.EquipmentSlot;
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.attribute.*;
 import net.minecraft.item.*;
-import net.minecraft.network.packet.s2c.play.EntityVelocityUpdateS2CPacket;
-import net.minecraft.server.network.ServerPlayerEntity;
 
 public class PolearmItem extends SwordItem {
     protected static final UUID ATTACK_RANGE_MODIFIER_ID = UUID.fromString("A7B3659C-AA74-469C-963A-09A391DCAA0F");
@@ -57,11 +56,10 @@ public class PolearmItem extends SwordItem {
         boolean tooNear = target.distanceTo(attacker) <= 2;
         stack.damage(tooNear ? 4 : 1, attacker, e -> e.sendEquipmentBreakStatus(EquipmentSlot.MAINHAND));
         target.takeKnockback(0.15, attacker.getX() - target.getX(), attacker.getZ() - target.getZ());
+        Living.updateVelocity(target);
         if (tooNear) {
             attacker.takeKnockback(attacker.getRandom().nextTriangular(0.4, 0.2), target.getX() - attacker.getX(), target.getZ() - attacker.getZ());
-            if (attacker instanceof ServerPlayerEntity ply) {
+            Living.updateVelocity(attacker);
-                ply.networkHandler.sendPacket(new EntityVelocityUpdateS2CPacket(ply));
-            }
         }
 
         return true;

src/main/java/com/minelittlepony/unicopia/projectile/ProjectileUtil.java

@@ -2,6 +2,7 @@ package com.minelittlepony.unicopia.projectile;
 
 import org.jetbrains.annotations.Nullable;
 
+import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.mixin.MixinPersistentProjectileEntity;
 
 import net.minecraft.entity.Entity;
@@ -50,6 +51,7 @@ public interface ProjectileUtil {
             Vec3d vel = throwable.getVelocity();
 
             throwable.addVelocity(heading.x - vel.x, heading.y - vel.y, heading.z - vel.z);
+            Living.updateVelocity(throwable);
         }
     }