From dc7b708556e851f5db62427f2fd91820398e21ea Mon Sep 17 00:00:00 2001
From: RK_01 <50594595+RaphiMC@users.noreply.github.com>
Date: Tue, 8 Oct 2024 21:35:43 +0200
Subject: [PATCH] Fix PLAYER_POSITION delta movement (#7)

---
 .../rewriter/EntityPacketRewriter1_21_2.java      | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/rewriter/EntityPacketRewriter1_21_2.java b/common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/rewriter/EntityPacketRewriter1_21_2.java
index d6f518766..ac64be583 100644
--- a/common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/rewriter/EntityPacketRewriter1_21_2.java
+++ b/common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/rewriter/EntityPacketRewriter1_21_2.java
@@ -137,11 +137,16 @@ public final class EntityPacketRewriter1_21_2 extends EntityRewriter<Clientbound
             wrapper.passthrough(Types.FLOAT); // Y rot
             wrapper.passthrough(Types.FLOAT); // X rot
 
-            // Add new delta movement flags so their current veloticy is kept
-            int relativeArguments = wrapper.read(Types.BYTE);
-            relativeArguments |= 1 << 5;
-            relativeArguments |= 1 << 6;
-            relativeArguments |= 1 << 7;
+            int relativeArguments = wrapper.read(Types.BYTE) & 0b00011111;
+            if ((relativeArguments & (1 << 0)) != 0) { // relative X
+                relativeArguments |= 1 << 5; // relative delta movement X
+            }
+            if ((relativeArguments & (1 << 1)) != 0) { // relative Y
+                relativeArguments |= 1 << 6; // relative delta movement Y
+            }
+            if ((relativeArguments & (1 << 2)) != 0) { // relative Z
+                relativeArguments |= 1 << 7; // relative delta movement Z
+            }
             wrapper.write(Types.INT, relativeArguments);
 
             final int teleportId = wrapper.read(Types.VAR_INT);