From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 15 Aug 2017 22:29:12 -0400
Subject: [PATCH] Expand World.spawnParticle API and add Builder

Adds ability to control who receives it and who is the source/sender (vanish API)
the standard API is to send the packet to everyone in the world, which is ineffecient.
Adds an option to control the force mode of the particle.

This adds a new Builder API which is much friendlier to use.

diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index f2eefdeab44ad4f7c0abd0e55e688e74a83abfff..e5aea9a58dae2342e13bdd8427a35a1845731b45 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -1717,12 +1717,17 @@ public class ServerLevel extends Level implements WorldGenLevel {
     }
 
     public <T extends ParticleOptions> int sendParticles(ServerPlayer sender, T t0, double d0, double d1, double d2, int i, double d3, double d4, double d5, double d6, boolean force) {
+        // Paper start - Particle API Expansion
+        return sendParticles(this.players(), sender, t0, d0, d1, d2, i, d3, d4, d5, d6, force);
+    }
+    public <T extends ParticleOptions> int sendParticles(List<ServerPlayer> receivers, @Nullable ServerPlayer sender, T t0, double d0, double d1, double d2, int i, double d3, double d4, double d5, double d6, boolean force) {
+        // Paper end
         ClientboundLevelParticlesPacket packetplayoutworldparticles = new ClientboundLevelParticlesPacket(t0, force, d0, d1, d2, (float) d3, (float) d4, (float) d5, (float) d6, i);
         // CraftBukkit end
         int j = 0;
 
-        for (int k = 0; k < this.players.size(); ++k) {
-            ServerPlayer entityplayer = (ServerPlayer) this.players.get(k);
+        for (Player entityhuman : receivers) { // Paper - Particle API Expansion
+            ServerPlayer entityplayer = (ServerPlayer) entityhuman; // Paper - Particle API Expansion
             if (sender != null && !entityplayer.getBukkitEntity().canSee(sender.getBukkitEntity())) continue; // CraftBukkit
 
             if (this.sendParticles(entityplayer, force, d0, d1, d2, packetplayoutworldparticles)) { // CraftBukkit
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index 125c55c0c80772ec9bd65ea2ddcd5e2dbaa0f332..82be61dffb993b2491890be42a114e1e4c59fc0f 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -1857,12 +1857,18 @@ public class CraftWorld extends CraftRegionAccessor implements World {
 
     @Override
     public <T> void spawnParticle(Particle<T> particle, double x, double y, double z, int count, double offsetX, double offsetY, double offsetZ, double extra, T data, boolean force) {
+        // Paper start - Particle API Expansion
+        this.spawnParticle(particle, null, null, x, y, z, count, offsetX, offsetY, offsetZ, extra, data, force);
+    }
+    public <T> void spawnParticle(Particle<T> particle, List<Player> receivers, Player sender, double x, double y, double z, int count, double offsetX, double offsetY, double offsetZ, double extra, T data, boolean force) {
         data = CraftParticle.convertLegacy(data);
-        if (data != null) {
+        if (data != null && !particle.getDataType().isInstance(data)) {
+            // Paper end
             Preconditions.checkArgument(particle.getDataType().isInstance(data), "data (%s) should be %s", data.getClass(), particle.getDataType());
         }
         this.getHandle().sendParticles(
-                null, // Sender
+                receivers == null ? this.getHandle().players() : receivers.stream().map(player -> ((CraftPlayer) player).getHandle()).collect(java.util.stream.Collectors.toList()), // Paper -  Particle API Expansion
+                sender != null ? ((CraftPlayer) sender).getHandle() : null, // Sender // Paper - Particle API Expansion
                 ((CraftParticle<T>) particle).createParticleParam(data), // Particle
                 x, y, z, // Position
                 count,  // Count