From a039ea62a91a5cdc873c341fad30491d8d770df1 Mon Sep 17 00:00:00 2001
From: SashegDev <gdsasheg@gmail.com>
Date: Wed, 30 Sep 2026 09:26:22 +0000
Subject: [PATCH] feat(delta): hook Display tracking budget through
 TrackingRange (no MC patch needed)

---
 .../java/me/sashegdev/delta/DeltaTracking.java | 18 ++++++++++++++++++
 .../main/java/org/spigotmc/TrackingRange.java  |  7 ++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/paper-server/src/main/java/me/sashegdev/delta/DeltaTracking.java b/paper-server/src/main/java/me/sashegdev/delta/DeltaTracking.java
index f94887439..43430ab4c 100644
--- a/paper-server/src/main/java/me/sashegdev/delta/DeltaTracking.java
+++ b/paper-server/src/main/java/me/sashegdev/delta/DeltaTracking.java
@@ -18,6 +18,24 @@ public final class DeltaTracking {
     private DeltaTracking() {
     }
 
+    /**
+     * Клампит дальность трекинга Display-сущностей.
+     * Вызывается из {@code org.spigotmc.TrackingRange#getEntityTrackingRange},
+     * который сам лежит в git-отслеживаемом исходнике Paper — поэтому патчить
+     * декомпилированный код Minecraft не требуется.
+     *
+     * @param range дальность из spigot.yml ({@code entity-tracking-range.display})
+     * @return эффективную дальность
+     */
+    public static int clampDisplayRange(final int range) {
+        final DeltaConfig cfg = delta();
+        if (cfg == null || !cfg.displayTrackingRangeEnabled) {
+            return range;
+        }
+        final int configured = cfg.displayTrackingRange;
+        return configured <= 0 ? range : Math.min(range, configured);
+    }
+
     /**
      * @return эффективную дальность трекинга с учётом Delta-конфига
      */
diff --git a/paper-server/src/main/java/org/spigotmc/TrackingRange.java b/paper-server/src/main/java/org/spigotmc/TrackingRange.java
index 05db2aab7..4a71022b1 100644
--- a/paper-server/src/main/java/org/spigotmc/TrackingRange.java
+++ b/paper-server/src/main/java/org/spigotmc/TrackingRange.java
@@ -45,7 +45,12 @@ public final class TrackingRange {
         if (entity instanceof ItemFrame || entity instanceof Painting || entity instanceof ItemEntity || entity instanceof ExperienceOrb) {
             return config.miscTrackingRange;
         } else if (entity instanceof Display) {
-            return config.displayTrackingRange;
+            // Delta start - optional Display range budget (paper-global.yml -> delta)
+            // Display entities have no physics, collision or gameplay meaning, so trimming
+            // their tracking range is safe: the client stops seeing them, server state
+            // stays correct. Off by default so stock Paper behaviour is unchanged.
+            return me.sashegdev.delta.DeltaTracking.clampDisplayRange(config.displayTrackingRange);
+            // Delta end
         } else {
             if (entity instanceof net.minecraft.world.entity.boss.enderdragon.EnderDragon) {
                 // Exempt ender dragon