From b26e74c3827b14a11466d9e2ada28d673ac5dace Mon Sep 17 00:00:00 2001
From: p2r3 <p2r3@p2r3.com>
Date: Thu, 28 Aug 2025 01:50:12 +0300
Subject: [PATCH] add option to disable fluid calculation

---
 include/globals.h |  2 ++
 src/procedures.c  | 24 ++++++++++++++----------
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/include/globals.h b/include/globals.h
index c45295b..2caac1e 100644
--- a/include/globals.h
+++ b/include/globals.h
@@ -39,6 +39,8 @@
 // broadcast based on the amount of players, reducing overhead for higher
 // player counts. For very many players, makes movement look jittery.
 #define SCALE_MOVEMENT_UPDATES_TO_PLAYER_COUNT
+// If defined, calculates fluid flow when blocks are updated near fluids
+#define DO_FLUID_FLOW
 
 // If defined, logs unrecognized packet IDs
 // #define DEV_LOG_UNKNOWN_PACKETS
diff --git a/src/procedures.c b/src/procedures.c
index a2b0544..5b13ae2 100644
--- a/src/procedures.c
+++ b/src/procedures.c
@@ -768,11 +768,13 @@ void handlePlayerAction (PlayerData *player, int action, short x, short y, short
 
   // Update nearby fluids
   uint8_t block_above = getBlockAt(x, y + 1, z);
-  checkFluidUpdate(x, y + 1, z, block_above);
-  checkFluidUpdate(x - 1, y, z, getBlockAt(x - 1, y, z));
-  checkFluidUpdate(x + 1, y, z, getBlockAt(x + 1, y, z));
-  checkFluidUpdate(x, y, z - 1, getBlockAt(x, y, z - 1));
-  checkFluidUpdate(x, y, z + 1, getBlockAt(x, y, z + 1));
+  #ifdef DO_FLUID_FLOW
+    checkFluidUpdate(x, y + 1, z, block_above);
+    checkFluidUpdate(x - 1, y, z, getBlockAt(x - 1, y, z));
+    checkFluidUpdate(x + 1, y, z, getBlockAt(x + 1, y, z));
+    checkFluidUpdate(x, y, z - 1, getBlockAt(x, y, z - 1));
+    checkFluidUpdate(x, y, z + 1, getBlockAt(x, y, z + 1));
+  #endif
 
   // Check if any blocks above this should break, and if so,
   // iterate upward over all blocks in the column and break them
@@ -885,11 +887,13 @@ void handlePlayerUseItem (PlayerData *player, short x, short y, short z, uint8_t
     // Apply server-side block change
     makeBlockChange(x, y, z, block);
     // Calculate fluid flow
-    checkFluidUpdate(x, y + 1, z, getBlockAt(x, y + 1, z));
-    checkFluidUpdate(x - 1, y, z, getBlockAt(x - 1, y, z));
-    checkFluidUpdate(x + 1, y, z, getBlockAt(x + 1, y, z));
-    checkFluidUpdate(x, y, z - 1, getBlockAt(x, y, z - 1));
-    checkFluidUpdate(x, y, z + 1, getBlockAt(x, y, z + 1));
+    #ifdef DO_FLUID_FLOW
+      checkFluidUpdate(x, y + 1, z, getBlockAt(x, y + 1, z));
+      checkFluidUpdate(x - 1, y, z, getBlockAt(x - 1, y, z));
+      checkFluidUpdate(x + 1, y, z, getBlockAt(x + 1, y, z));
+      checkFluidUpdate(x, y, z - 1, getBlockAt(x, y, z - 1));
+      checkFluidUpdate(x, y, z + 1, getBlockAt(x, y, z + 1));
+    #endif
   }
 
   // Sync hotbar contents to player