Add option to fix delayed shield blocking (#2415)

api/src/main/java/us/myles/ViaVersion/api/ViaVersionConfig.java

@@ -76,6 +76,13 @@ public interface ViaVersionConfig {
      */
     boolean isShieldBlocking();
 
+    /**
+     * Whether the player can block with the shield without a delay.
+     *
+     * @return {@code true} if non delayed shield blocking is enabled.
+     */
+    boolean isNoDelayShieldBlocking();
+
     /**
      * Get if armor stand positions are fixed so holograms show up at the correct height in 1.9 & 1.10
      *

common/src/main/java/us/myles/ViaVersion/AbstractViaConfig.java

@@ -32,6 +32,7 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
     private boolean useNewDeathmessages;
     private boolean suppressMetadataErrors;
     private boolean shieldBlocking;
+    private boolean noDelayShieldBlocking;
     private boolean hologramPatch;
     private boolean pistonAnimationPatch;
     private boolean bossbarPatch;
@@ -91,6 +92,7 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         useNewDeathmessages = getBoolean("use-new-deathmessages", true);
         suppressMetadataErrors = getBoolean("suppress-metadata-errors", false);
         shieldBlocking = getBoolean("shield-blocking", true);
+        noDelayShieldBlocking = getBoolean("no-delay-shield-blocking", false);
         hologramPatch = getBoolean("hologram-patch", false);
         pistonAnimationPatch = getBoolean("piston-animation-patch", false);
         bossbarPatch = getBoolean("bossbar-patch", true);
@@ -170,6 +172,11 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         return shieldBlocking;
     }
 
+    @Override
+    public boolean isNoDelayShieldBlocking() {
+        return noDelayShieldBlocking;
+    }
+
     @Override
     public boolean isHologramPatch() {
         return hologramPatch;

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9to1_8/packets/WorldPackets.java

@@ -303,6 +303,12 @@ public class WorldPackets {
                                         Item shield = new Item(442, (byte) 1, (short) 0, null);
                                         tracker.setSecondHand(shield);
                                     }
+                                }
+
+                                // Uses left or right hand to start blocking depending on the no delay setting
+                                boolean noDelayBlocking = Via.getConfig().isNoDelayShieldBlocking();
+
+                                if (noDelayBlocking && hand == 1 || !noDelayBlocking && hand == 0) {
                                     wrapper.cancel();
                                 }
                             } else {

common/src/main/resources/assets/viaversion/config.yml

@@ -167,6 +167,9 @@ auto-team: true
 suppress-metadata-errors: false
 # When enabled 1.9+ will be able to block by using shields
 shield-blocking: true
+# If this setting is active, the main hand is used instead of the off hand to trigger the blocking of the player.
+# With the main hand the blocking starts way faster.
+no-delay-shield-blocking: false
 # Enable player tick simulation, this fixes eating, drinking, nether portals.
 simulate-pt: true
 # Should we use nms player to simulate packets, (may fix anti-cheat issues)