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..68257f257dd3b167e237482c8d149590103896b2 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(players, sender, t0, d0, d1, d2, i, d3, d4, d5, d6, force);
+    }
+    public <T extends ParticleOptions> int sendParticles(List<ServerPlayer> receivers, 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 d348ca56ae452dc80d5dabe874d9f8d72970fc4d..0476f00719d180d28a2a4bab3f4152b00a1e4e67 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -1863,11 +1863,17 @@ public class CraftWorld extends CraftRegionAccessor implements World {
 
     @Override
     public <T> void spawnParticle(Particle particle, double x, double y, double z, int count, double offsetX, double offsetY, double offsetZ, double extra, T data, boolean force) {
-        if (data != null) {
+        // Paper start - Particle API Expansion
+        spawnParticle(particle, null, null, x, y, z, count, offsetX, offsetY, offsetZ, extra, data, force);
+    }
+    public <T> void spawnParticle(Particle 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) {
+        // Paper end
+        if (data != null && !particle.getDataType().isInstance(data)) {
             Preconditions.checkArgument(particle.getDataType().isInstance(data), "data (%s) should be %s", data.getClass(), particle.getDataType());
         }
         this.getHandle().sendParticles(
-                null, // Sender
+                receivers == null ? 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.toNMS(particle, data), // Particle
                 x, y, z, // Position
                 count,  // Count