Added a health drain particle for changelings, fixed changeling feed having too wide of a radius, and fixed particles not spawning on the clients

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

@@ -8,6 +8,7 @@ import javax.annotation.Nullable;
 import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.data.Hit;
 import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.particle.FollowingParticleEffect;
 import com.minelittlepony.unicopia.particle.ParticleUtils;
 import com.minelittlepony.unicopia.particle.UParticles;
 import com.minelittlepony.unicopia.util.MagicalDamageSource;
@@ -79,7 +80,7 @@ public class ChangelingFeedAbility implements Ability<Hit> {
     }
 
     protected List<LivingEntity> getTargets(Pony player) {
-        List<Entity> list = VecHelper.findInReach(player.getMaster(), 3, this::canDrain);
+        List<Entity> list = VecHelper.findInRange(player.getMaster(), player.getWorld(), player.getOriginVector(), 3, this::canDrain);
 
         RayTraceHelper.<LivingEntity>findEntity(player.getMaster(), 17, 1,
                 looked -> looked instanceof LivingEntity && !list.contains(looked) && canDrain(looked))
@@ -122,6 +123,7 @@ public class ChangelingFeedAbility implements Ability<Hit> {
     }
 
     public float drainFrom(PlayerEntity changeling, LivingEntity living) {
+
         DamageSource d = MagicalDamageSource.create("feed", changeling);
 
         float damage = living.getHealth()/2;
@@ -131,6 +133,7 @@ public class ChangelingFeedAbility implements Ability<Hit> {
         }
 
         ParticleUtils.spawnParticles(UParticles.CHANGELING_MAGIC, living, 7);
+        ParticleUtils.spawnParticles(new FollowingParticleEffect(UParticles.HEALTH_DRAIN, changeling, 0.2F), living, 1);
 
         if (changeling.hasStatusEffect(StatusEffects.NAUSEA)) {
             StatusEffectInstance effect = changeling.getStatusEffect(StatusEffects.NAUSEA);

src/main/java/com/minelittlepony/unicopia/client/URenderers.java

@@ -3,6 +3,7 @@ package com.minelittlepony.unicopia.client;
 import com.minelittlepony.unicopia.UEntities;
 import com.minelittlepony.unicopia.client.particle.ChangelingMagicParticle;
 import com.minelittlepony.unicopia.client.particle.DiskParticle;
+import com.minelittlepony.unicopia.client.particle.HealthDrainParticle;
 import com.minelittlepony.unicopia.client.particle.MagicParticle;
 import com.minelittlepony.unicopia.client.particle.RainboomParticle;
 import com.minelittlepony.unicopia.client.particle.RainbowTrailParticle;
@@ -24,6 +25,7 @@ public interface URenderers {
         ParticleFactoryRegistry.getInstance().register(UParticles.UNICORN_MAGIC, createFactory(MagicParticle::new));
         ParticleFactoryRegistry.getInstance().register(UParticles.CHANGELING_MAGIC, createFactory(ChangelingMagicParticle::new));
         ParticleFactoryRegistry.getInstance().register(UParticles.RAIN_DROPS, createFactory(RaindropsParticle::new));
+        ParticleFactoryRegistry.getInstance().register(UParticles.HEALTH_DRAIN, createFactory(HealthDrainParticle::new));
         ParticleFactoryRegistry.getInstance().register(UParticles.RAINBOOM_RING, RainboomParticle::new);
         ParticleFactoryRegistry.getInstance().register(UParticles.RAINBOOM_TRAIL, RainbowTrailParticle::new);
         ParticleFactoryRegistry.getInstance().register(UParticles.SPHERE, SphereParticle::new);
@@ -33,10 +35,10 @@ public interface URenderers {
     }
 
     static <T extends ParticleEffect> PendingParticleFactory<T> createFactory(ParticleSupplier<T> supplier) {
-        return provider -> (effect, world, x, y, z, dx, dy, dz) -> supplier.get(provider, world, x, y, z, dx, dy, dz);
+        return provider -> (effect, world, x, y, z, dx, dy, dz) -> supplier.get(effect, provider, world, x, y, z, dx, dy, dz);
     }
 
     interface ParticleSupplier<T extends ParticleEffect> {
-        Particle get(SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz);
+        Particle get(T effect, SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz);
     }
 }

src/main/java/com/minelittlepony/unicopia/client/particle/ChangelingMagicParticle.java

@@ -2,13 +2,14 @@ package com.minelittlepony.unicopia.client.particle;
 
 import net.minecraft.client.particle.SpriteProvider;
 import net.minecraft.client.world.ClientWorld;
+import net.minecraft.particle.ParticleEffect;
 
 public class ChangelingMagicParticle extends MagicParticle {
 
     private final SpriteProvider provider;
 
-    public ChangelingMagicParticle(SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz) {
+    public ChangelingMagicParticle(ParticleEffect effect, SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz) {
-        super(provider, world, x, y, z, dx, dy, dz, 1, 1, 1);
+        super(effect, provider, world, x, y, z, dx, dy, dz, 1, 1, 1);
         this.provider = provider;
 
         float intensity = random.nextFloat() * 0.6F + 0.4F;

src/main/java/com/minelittlepony/unicopia/client/particle/HealthDrainParticle.java

@@ -0,0 +1,48 @@
+package com.minelittlepony.unicopia.client.particle;
+
+import com.minelittlepony.unicopia.particle.FollowingParticleEffect;
+
+import net.minecraft.client.particle.ParticleTextureSheet;
+import net.minecraft.client.particle.SpriteBillboardParticle;
+import net.minecraft.client.particle.SpriteProvider;
+import net.minecraft.client.world.ClientWorld;
+import net.minecraft.util.math.Vec3d;
+
+public class HealthDrainParticle extends SpriteBillboardParticle {
+
+    private final FollowingParticleEffect effect;
+
+    public HealthDrainParticle(FollowingParticleEffect effect, SpriteProvider provider, ClientWorld world, double x, double y, double z, double velocityX, double velocityY, double velocityZ) {
+        super(world, x, y, z, velocityX, velocityY, velocityZ);
+        setSprite(provider);
+        setMaxAge(3);
+        scale(0.125F);
+        this.effect = effect;
+        this.collidesWithWorld = false;
+    }
+
+    @Override
+    public ParticleTextureSheet getType() {
+        return ParticleTextureSheet.PARTICLE_SHEET_TRANSLUCENT;
+    }
+
+    @Override
+    public void tick() {
+        super.tick();
+
+        Vec3d target = effect.getTarget(world);
+        Vec3d pos = new Vec3d(x, y, z);
+
+        if (this.scale * 1.5F < 0.5F) {
+            scale(1.5F);
+        }
+
+        double distance = pos.distanceTo(target);
+        if (distance > 1) {
+            age = 0;
+        }
+
+        Vec3d motion = target.subtract(pos).normalize().multiply(Math.min(distance, effect.getSpeed()));
+        move(motion.x, motion.y, motion.z);
+    }
+}

src/main/java/com/minelittlepony/unicopia/client/particle/MagicParticle.java

@@ -4,13 +4,14 @@ import net.minecraft.client.particle.ParticleTextureSheet;
 import net.minecraft.client.particle.SpriteBillboardParticle;
 import net.minecraft.client.particle.SpriteProvider;
 import net.minecraft.client.world.ClientWorld;
+import net.minecraft.particle.ParticleEffect;
 
 public class MagicParticle extends SpriteBillboardParticle {
     private double startX;
     private double startY;
     private double startZ;
 
-    MagicParticle(SpriteProvider provider, ClientWorld w, double x, double y, double z, double vX, double vY, double vZ, float r, float g, float b) {
+    MagicParticle(ParticleEffect effect, SpriteProvider provider, ClientWorld w, double x, double y, double z, double vX, double vY, double vZ, float r, float g, float b) {
         super(w, x, y, z);
         setSprite(provider);
 
@@ -28,8 +29,8 @@ public class MagicParticle extends SpriteBillboardParticle {
         colorBlue = b;
     }
 
-    public MagicParticle(SpriteProvider provider, ClientWorld w, double x, double y, double z, double vX, double vY, double vZ) {
+    public MagicParticle(ParticleEffect effect, SpriteProvider provider, ClientWorld w, double x, double y, double z, double vX, double vY, double vZ) {
-        this(provider, w, x, y, z, vX, vY, vZ, 1, 1, 1);
+        this(effect, provider, w, x, y, z, vX, vY, vZ, 1, 1, 1);
 
         colorAlpha = 0.7F;
         colorGreen *= 0.3F;

src/main/java/com/minelittlepony/unicopia/client/particle/RaindropsParticle.java

@@ -3,10 +3,11 @@ package com.minelittlepony.unicopia.client.particle;
 import net.minecraft.client.particle.RainSplashParticle;
 import net.minecraft.client.particle.SpriteProvider;
 import net.minecraft.client.world.ClientWorld;
+import net.minecraft.particle.ParticleEffect;
 
 public class RaindropsParticle extends RainSplashParticle {
 
-    public RaindropsParticle(SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz) {
+    public RaindropsParticle(ParticleEffect effect, SpriteProvider provider, ClientWorld world, double x, double y, double z, double dx, double dy, double dz) {
         super(world, x, y, z);
         velocityY = -0.1;
         maxAge += 19;

src/main/java/com/minelittlepony/unicopia/particle/FollowingParticleEffect.java

@@ -0,0 +1,96 @@
+package com.minelittlepony.unicopia.particle;
+
+import java.util.Locale;
+import com.mojang.brigadier.StringReader;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+
+import net.minecraft.particle.ParticleEffect;
+import net.minecraft.particle.ParticleType;
+import net.minecraft.entity.Entity;
+import net.minecraft.network.PacketByteBuf;
+import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.registry.Registry;
+import net.minecraft.world.World;
+
+public class FollowingParticleEffect implements ParticleEffect {
+    public static final ParticleEffect.Factory<FollowingParticleEffect> FACTORY = new ParticleEffect.Factory<FollowingParticleEffect>() {
+        @Override
+        public FollowingParticleEffect read(ParticleType<FollowingParticleEffect> type, StringReader reader) throws CommandSyntaxException {
+            reader.expect(' ');
+            double x = reader.readDouble();
+            reader.expect(' ');
+            double y = reader.readDouble();
+            reader.expect(' ');
+            double z = reader.readDouble();
+            reader.expect(' ');
+            float speed = reader.readFloat();
+            return new FollowingParticleEffect(type, -1, new Vec3d(x, y, z), speed);
+        }
+
+        @Override
+        public FollowingParticleEffect read(ParticleType<FollowingParticleEffect> particleType, PacketByteBuf buf) {
+            return new FollowingParticleEffect(particleType, buf.readInt(), new Vec3d(buf.readDouble(), buf.readDouble(), buf.readDouble()), buf.readFloat());
+        }
+    };
+
+    private final ParticleType<FollowingParticleEffect> type;
+
+    private Vec3d fixedTarget;
+
+    private int movingTarget;
+
+    private final float followSpeed;
+
+    public FollowingParticleEffect(ParticleType<FollowingParticleEffect> type, Vec3d target, float followSpeed) {
+        this.type = type;
+        this.fixedTarget = target;
+        this.movingTarget = -1;
+        this.followSpeed = followSpeed;
+    }
+
+    public FollowingParticleEffect(ParticleType<FollowingParticleEffect> type, Entity target, float followSpeed) {
+        this(type, target.getEntityId(), target.getCameraPosVec(1), followSpeed);
+    }
+
+    private FollowingParticleEffect(ParticleType<FollowingParticleEffect> type, int movingTarget, Vec3d fixedTarget, float followSpeed) {
+        this.type = type;
+        this.movingTarget = movingTarget;
+        this.fixedTarget = fixedTarget;
+        this.followSpeed = followSpeed;
+    }
+
+    public Vec3d getTarget(World world) {
+        if (movingTarget > -1) {
+            Entity e = world.getEntityById(movingTarget);
+            if (e != null) {
+                fixedTarget = e.getCameraPosVec(1);
+            } else {
+                movingTarget = -1;
+            }
+        }
+        return fixedTarget;
+    }
+
+    public float getSpeed() {
+        return followSpeed;
+    }
+
+    @Override
+    public ParticleType<?> getType() {
+        return type;
+    }
+
+    @Override
+    public void write(PacketByteBuf buf) {
+        buf.writeInt(movingTarget);
+        buf.writeDouble(fixedTarget.x);
+        buf.writeDouble(fixedTarget.y);
+        buf.writeDouble(fixedTarget.z);
+    }
+
+    @Override
+    public String asString() {
+        return String.format(Locale.ROOT, "%s %.2f %.2f %.2f %.2f", Registry.PARTICLE_TYPE.getId(getType()), fixedTarget.x, fixedTarget.y, fixedTarget.z, followSpeed);
+    }
+
+}

src/main/java/com/minelittlepony/unicopia/particle/ParticleUtils.java

@@ -5,6 +5,8 @@ import com.minelittlepony.unicopia.util.shape.Sphere;
 
 import net.minecraft.entity.Entity;
 import net.minecraft.particle.ParticleEffect;
+import net.minecraft.server.world.ServerWorld;
+import net.minecraft.world.World;
 
 /**
  * Utility for spawning particles.
@@ -18,11 +20,20 @@ public final class ParticleUtils {
         Shape shape = new Sphere(false, Math.abs((float)halfDist + entity.getWidth()));
 
         shape.randomPoints(count, entity.world.random).forEach(point -> {
-            entity.world.addParticle(particleId,
+            spawnParticle(entity.world, particleId,
                     entity.getX() + point.x,
                     middle + point.y,
                     entity.getZ() + point.z,
                     0, 0, 0);
         });
     }
+
+    public static void spawnParticle(World world, ParticleEffect effect, double x, double y, double z, double vX, double vY, double vZ) {
+        if (world instanceof ServerWorld) {
+            ((ServerWorld)world).spawnParticles(effect, x, y, z, 1, vX, vY, vZ, 0);
+        } else {
+            world.addParticle(effect, x, y, z, vX, vY, vZ);
+        }
+
+    }
 }

src/main/java/com/minelittlepony/unicopia/particle/UParticles.java

@@ -19,6 +19,8 @@ public interface UParticles {
     ParticleType<SphereParticleEffect> SPHERE = register("sphere", FabricParticleTypes.complex(true, SphereParticleEffect.FACTORY));
     ParticleType<DiskParticleEffect> DISK = register("disk", FabricParticleTypes.complex(true, DiskParticleEffect.FACTORY));
 
+    ParticleType<FollowingParticleEffect> HEALTH_DRAIN = register("health_drain", FabricParticleTypes.complex(true, FollowingParticleEffect.FACTORY));
+
     static <T extends ParticleType<?>> T register(String name, T type) {
         return Registry.register(Registry.PARTICLE_TYPE, new Identifier("unicopia", name), type);
     }

src/main/java/com/minelittlepony/unicopia/util/VecHelper.java

@@ -5,7 +5,6 @@ import java.util.function.Predicate;
 import javax.annotation.Nullable;
 
 import net.minecraft.entity.Entity;
-import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.util.math.Box;
 import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.World;
@@ -23,17 +22,4 @@ public interface VecHelper {
     static List<Entity> findInRange(@Nullable Entity origin, World w, Vec3d pos, double radius, @Nullable Predicate<Entity> predicate) {
         return w.getOtherEntities(origin, Box.method_29968(pos).expand(radius), predicate == null ? inRange(pos, radius) : inRange(pos, radius).and(predicate));
     }
-
-
-    /**
-     * Gets all entities within a given range from the player.
-     */
-    static List<Entity> findInReach(PlayerEntity player, double reach, @Nullable Predicate<? super Entity> predicate) {
-        Vec3d look = player.getCameraPosVec(1).multiply(reach);
-
-        return player.world.getOtherEntities(player, player
-                .getBoundingBox()
-                .expand(look.x, look.y, look.z)
-                .expand(1, 1, 1), predicate);
-    }
 }

src/main/resources/assets/unicopia/particles/health_drain.json

@@ -0,0 +1,5 @@
+{
+  "textures": [
+    "minecraft:heart"
+  ]
+}