From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Fri, 29 Apr 2016 20:02:00 -0400
Subject: [PATCH] Improve Maps (in item frames) performance and bug fixes

Maps used a modified version of rendering to support plugin controlled
imaging on maps. The Craft Map Renderer is much slower than Vanilla,
causing maps in item frames to cause a noticeable hit on server performance.

This updates the map system to not use the Craft system if we detect that no
custom renderers are in use, defaulting to the much simpler Vanilla system.

Additionally, numerous issues to player position tracking on maps has been fixed.

diff --git a/src/main/java/net/minecraft/server/EntityHuman.java b/src/main/java/net/minecraft/server/EntityHuman.java
index 1f20fbbf92c9d2937594c924837fff0bb9ee9238..0e8ba05455161883c86df6606104fab3529c3c0c 100644
--- a/src/main/java/net/minecraft/server/EntityHuman.java
+++ b/src/main/java/net/minecraft/server/EntityHuman.java
@@ -615,6 +615,12 @@ public abstract class EntityHuman extends EntityLiving {
                 return null;
             }
             // CraftBukkit end
+            // Paper start - remove player from map on drop
+            if (itemstack.getItem() == Items.FILLED_MAP) {
+                WorldMap worldmap = ItemWorldMap.getSavedMap(itemstack, this.world);
+                worldmap.updateSeenPlayers(this, itemstack);
+            }
+            // Paper end
 
             return entityitem;
         }
diff --git a/src/main/java/net/minecraft/server/WorldMap.java b/src/main/java/net/minecraft/server/WorldMap.java
index a56ac3da806035e853bb912ab874265ecbcd2753..2f1be1995d1a188da5be792abd7ac6f126332f49 100644
--- a/src/main/java/net/minecraft/server/WorldMap.java
+++ b/src/main/java/net/minecraft/server/WorldMap.java
@@ -31,6 +31,7 @@ public class WorldMap extends PersistentBase {
     private final Map<String, MapIconBanner> l = Maps.newHashMap();
     public final Map<String, MapIcon> decorations = Maps.newLinkedHashMap();
     private final Map<String, WorldMapFrame> m = Maps.newHashMap();
+    private org.bukkit.craftbukkit.map.RenderData vanillaRender = new org.bukkit.craftbukkit.map.RenderData(); // Paper
 
     // CraftBukkit start
     public final CraftMapView mapView;
@@ -43,6 +44,7 @@ public class WorldMap extends PersistentBase {
         // CraftBukkit start
         mapView = new CraftMapView(this);
         server = (CraftServer) org.bukkit.Bukkit.getServer();
+        vanillaRender.buffer = colors; // Paper
         // CraftBukkit end
     }
 
@@ -115,6 +117,7 @@ public class WorldMap extends PersistentBase {
                 this.l.put(mapiconbanner.f(), mapiconbanner);
                 this.a(mapiconbanner.c(), (GeneratorAccess) null, mapiconbanner.f(), (double) mapiconbanner.a().getX(), (double) mapiconbanner.a().getZ(), 180.0D, mapiconbanner.d());
             }
+        vanillaRender.buffer = colors; // Paper
 
             NBTTagList nbttaglist1 = nbttagcompound.getList("frames", 10);
 
@@ -190,6 +193,7 @@ public class WorldMap extends PersistentBase {
         this.b();
     }
 
+    public void updateSeenPlayers(EntityHuman entityhuman, ItemStack itemstack) { this.a(entityhuman, itemstack); } // Paper - OBFHELPER
     public void a(EntityHuman entityhuman, ItemStack itemstack) {
         if (!this.humans.containsKey(entityhuman)) {
             WorldMap.WorldMapHumanTracker worldmap_worldmaphumantracker = new WorldMap.WorldMapHumanTracker(entityhuman);
@@ -425,6 +429,21 @@ public class WorldMap extends PersistentBase {
 
     public class WorldMapHumanTracker {
 
+        // Paper start
+        private void addSeenPlayers(java.util.Collection<MapIcon> icons) {
+            org.bukkit.entity.Player player = (org.bukkit.entity.Player) trackee.getBukkitEntity();
+            WorldMap.this.decorations.forEach((name, mapIcon) -> {
+                // If this cursor is for a player check visibility with vanish system
+                org.bukkit.entity.Player other = org.bukkit.Bukkit.getPlayerExact(name); // Spigot
+                if (other == null || player.canSee(other)) {
+                    icons.add(mapIcon);
+                }
+            });
+        }
+        private boolean shouldUseVanillaMap() {
+            return mapView.getRenderers().size() == 1 && mapView.getRenderers().get(0).getClass() == org.bukkit.craftbukkit.map.CraftMapRenderer.class;
+        }
+        // Paper end
         public final EntityHuman trackee;
         private boolean d = true;
         private int e;
@@ -441,9 +460,12 @@ public class WorldMap extends PersistentBase {
         @Nullable
         public Packet<?> a(ItemStack itemstack) {
             // CraftBukkit start
-            org.bukkit.craftbukkit.map.RenderData render = WorldMap.this.mapView.render((org.bukkit.craftbukkit.entity.CraftPlayer) this.trackee.getBukkitEntity()); // CraftBukkit
+            if (!this.d && this.i % 5 != 0) { this.i++; return null; } // Paper - this won't end up sending, so don't render it!
+            boolean vanillaMaps = shouldUseVanillaMap(); // Paper
+            org.bukkit.craftbukkit.map.RenderData render = !vanillaMaps ? WorldMap.this.mapView.render((org.bukkit.craftbukkit.entity.CraftPlayer) this.trackee.getBukkitEntity()) : WorldMap.this.vanillaRender; // CraftBukkit // Paper
 
             java.util.Collection<MapIcon> icons = new java.util.ArrayList<MapIcon>();
+            if (vanillaMaps) addSeenPlayers(icons); // Paper
 
             for ( org.bukkit.map.MapCursor cursor : render.cursors) {
 
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index 532b5a4743fb2216ba3c1b61206cde4391275c8c..f3fe395d9e9b1332d51cd35b0cb20f606a4a481e 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -1090,6 +1090,7 @@ public class WorldServer extends World {
                         {
                             if ( iter.next().trackee == entity )
                             {
+                                map.decorations.remove(entity.getDisplayName().getString()); // Paper
                                 iter.remove();
                             }
                         }
diff --git a/src/main/java/org/bukkit/craftbukkit/map/RenderData.java b/src/main/java/org/bukkit/craftbukkit/map/RenderData.java
index 256a131781721c86dd6cdbc329335964570cbe8c..5768cd512ec166f1e8d1f4a28792015347297c3f 100644
--- a/src/main/java/org/bukkit/craftbukkit/map/RenderData.java
+++ b/src/main/java/org/bukkit/craftbukkit/map/RenderData.java
@@ -5,7 +5,7 @@ import org.bukkit.map.MapCursor;
 
 public class RenderData {
 
-    public final byte[] buffer;
+    public byte[] buffer; // Paper
     public final ArrayList<MapCursor> cursors;
 
     public RenderData() {
