From ba03d92ad0f2cea409a94486a86dbe26bc161aa3 Mon Sep 17 00:00:00 2001
From: anmol-patankar <anmolpatankar@gmail.com>
Date: Fri, 12 Sep 2025 22:23:08 +0530
Subject: [PATCH] fix mobs spawning in water

* Fixed underwater under lava mob spawn issue #17

* made comment changes

* minor fix

* method name change

* method change

* fixed
---
 include/procedures.h | 1 +
 src/main.c           | 6 +++---
 src/procedures.c     | 9 +++++++++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/procedures.h b/include/procedures.h
index 4c97b61..819aa4a 100644
--- a/include/procedures.h
+++ b/include/procedures.h
@@ -28,6 +28,7 @@ uint8_t makeBlockChange (short x, uint8_t y, short z, uint8_t block);
 uint8_t isInstantlyMined (PlayerData *player, uint8_t block);
 uint8_t isColumnBlock (uint8_t block);
 uint8_t isPassableBlock (uint8_t block);
+uint8_t isPassableSpawnBlock (uint8_t block);
 uint8_t isReplaceableBlock (uint8_t block);
 uint32_t isCompostItem (uint16_t item);
 uint8_t getItemStackSize (uint16_t item);
diff --git a/src/main.c b/src/main.c
index b2f99e7..dd1266f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -355,10 +355,10 @@ void handlePacket (int client_fd, int length, int packet_id, int state) {
           uint8_t b_mid = getBlockAt(mob_x, mob_y, mob_z);
           uint8_t b_top = getBlockAt(mob_x, mob_y + 1, mob_z);
           while (mob_y < 255) {
-            if ( // Solid block below, non-solid at feet and above
+            if ( // Solid block below, non-solid(spawnable) at feet and above
               !isPassableBlock(b_low) &&
-              isPassableBlock(b_mid) &&
-              isPassableBlock(b_top)
+              isPassableSpawnBlock(b_mid) &&
+              isPassableSpawnBlock(b_top)
             ) break;
             b_low = b_mid;
             b_mid = b_top;
diff --git a/src/procedures.c b/src/procedures.c
index 24068dd..2e485b3 100644
--- a/src/procedures.c
+++ b/src/procedures.c
@@ -637,6 +637,15 @@ uint8_t isPassableBlock (uint8_t block) {
     block == B_torch
   );
 }
+// Checks whether the given block is non-solid and spawnable
+uint8_t isPassableSpawnBlock (uint8_t block) {
+    if ((block >= B_water && block < B_water + 8) ||
+        (block >= B_lava && block < B_lava + 4)) 
+    {
+        return 0;
+    }
+    return isPassableBlock(block);
+}
 
 // Checks whether the given block can be replaced by another block
 uint8_t isReplaceableBlock (uint8_t block) {