Fix strider attribute desync

GrimAnticheat · Sep 5, 2024 · e8c7b90 · e8c7b90
1 parent 7f0dbdb
commit e8c7b90
Showing 1 changed file with 31 additions and 3 deletions.
diff --git a/src/main/java/ac/grim/grimac/predictionengine/movementtick/MovementTickerStrider.java b/src/main/java/ac/grim/grimac/predictionengine/movementtick/MovementTickerStrider.java
@@ -1,15 +1,20 @@
 package ac.grim.grimac.predictionengine.movementtick;
 
 import ac.grim.grimac.player.GrimPlayer;
+import ac.grim.grimac.utils.data.attribute.ValuedAttribute;
 import ac.grim.grimac.utils.data.packetentity.PacketEntityStrider;
 import ac.grim.grimac.utils.nmsutil.BlockProperties;
 import com.github.retrooper.packetevents.protocol.attribute.Attributes;
 import com.github.retrooper.packetevents.protocol.player.ClientVersion;
 import com.github.retrooper.packetevents.protocol.world.states.defaulttags.BlockTags;
 import com.github.retrooper.packetevents.protocol.world.states.type.StateType;
+import com.github.retrooper.packetevents.resources.ResourceLocation;
 import com.github.retrooper.packetevents.util.Vector3d;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerUpdateAttributes;
 import org.bukkit.util.Vector;
 
+import java.util.ArrayList;
+
 public class MovementTickerStrider extends MovementTickerRideable {
 
     public MovementTickerStrider(GrimPlayer player) {
@@ -38,19 +43,42 @@ public void livingEntityAIStep() {
         StateType posMaterial = player.compensatedWorld.getStateTypeAt(player.x, player.y, player.z);
         StateType belowMaterial = BlockProperties.getOnPos(player, player.mainSupportingBlockData, new Vector3d(player.x, player.y, player.z));
 
-        ((PacketEntityStrider) player.compensatedEntities.getSelf().getRiding()).isShaking =
-                !BlockTags.STRIDER_WARM_BLOCKS.contains(posMaterial) &&
+        final PacketEntityStrider strider = (PacketEntityStrider) player.compensatedEntities.getSelf().getRiding();
+        strider.isShaking = !BlockTags.STRIDER_WARM_BLOCKS.contains(posMaterial) &&
                         !BlockTags.STRIDER_WARM_BLOCKS.contains(belowMaterial) &&
                         !player.wasTouchingLava;
     }
 
+    private static final WrapperPlayServerUpdateAttributes.PropertyModifier SUFFOCATING_MODIFIER = new WrapperPlayServerUpdateAttributes.PropertyModifier(
+            ResourceLocation.minecraft("suffocating"), -0.34F, WrapperPlayServerUpdateAttributes.PropertyModifier.Operation.MULTIPLY_BASE);
+
     @Override
     public float getSteeringSpeed() {
         PacketEntityStrider strider = (PacketEntityStrider) player.compensatedEntities.getSelf().getRiding();
         // Unsure which version the speed changed in
         final boolean newSpeed = player.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_20);
         final float coldSpeed = newSpeed ? 0.35F : 0.23F;
-        return (float) strider.getAttributeValue(Attributes.GENERIC_MOVEMENT_SPEED) * (strider.isShaking ? coldSpeed : 0.55F);
+
+        // Client desyncs the attribute
+        // Again I don't know when this was changed, or whether it always existed, so I will just put it behind 1.20+
+        final ValuedAttribute movementSpeedAttr = strider.getAttribute(Attributes.GENERIC_MOVEMENT_SPEED).get();
+        float updatedMovementSpeed = (float) movementSpeedAttr.get();
+        if (newSpeed) {
+            final WrapperPlayServerUpdateAttributes.Property lastProperty = movementSpeedAttr.property().orElse(null);
+            if (lastProperty != null && (!strider.isShaking || lastProperty.getModifiers().stream().noneMatch(mod -> mod.getName().getKey().equals("suffocating")))) {
+                WrapperPlayServerUpdateAttributes.Property newProperty = new WrapperPlayServerUpdateAttributes.Property(lastProperty.getAttribute(), lastProperty.getValue(), new ArrayList<>(lastProperty.getModifiers()));
+                if (!strider.isShaking) {
+                    newProperty.getModifiers().removeIf(modifier -> modifier.getName().getKey().equals("suffocating"));
+                } else {
+                    newProperty.getModifiers().add(SUFFOCATING_MODIFIER);
+                }
+                movementSpeedAttr.with(newProperty);
+                updatedMovementSpeed = (float) movementSpeedAttr.get();
+                movementSpeedAttr.with(lastProperty);
+            }
+        }
+
+        return updatedMovementSpeed * (strider.isShaking ? coldSpeed : 0.55F);
     }
 
     @Override