From 3b9ca68a5786f9eca56c21992b33dc1512222cde Mon Sep 17 00:00:00 2001
From: p2r3 <p2r3@p2r3.com>
Date: Tue, 12 Aug 2025 13:07:42 +0300
Subject: [PATCH] spawn players at terrain height level

---
 main.c         | 15 ++++++++++++++-
 src/tools.c    |  5 ++---
 src/worldgen.c |  3 +--
 src/worldgen.h |  5 ++++-
 4 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/main.c b/main.c
index 1d2095b..a730e6f 100644
--- a/main.c
+++ b/main.c
@@ -14,6 +14,7 @@
 #include "src/tools.h"
 #include "src/varnum.h"
 #include "src/packets.h"
+#include "src/worldgen.h"
 
 void handlePacket (int client_fd, int length, int packet_id) {
 
@@ -59,7 +60,19 @@ void handlePacket (int client_fd, int length, int packet_id) {
         PlayerData *player;
         if (getPlayerData(client_fd, &player)) break;
 
-        sc_synchronizePlayerPosition(client_fd, player->x, player->y, player->z, player->yaw * 180 / 127, player->pitch * 90 / 127);
+        if (player->y == -32767) { // is this a new player?
+
+          int _x = 8 / chunk_size;
+          int _z = 8 / chunk_size;
+          int rx = 8 % chunk_size;
+          int rz = 8 % chunk_size;
+
+          uint32_t chunk_hash = getChunkHash(_x, _z);
+          sc_synchronizePlayerPosition(client_fd, 8.5, getHeightAt(rx, rz, _x, _z, chunk_hash) + 1, 8.5, 0, 0);
+
+        } else {
+          sc_synchronizePlayerPosition(client_fd, player->x, player->y, player->z, player->yaw * 180 / 127, player->pitch * 90 / 127);
+        }
 
         for (uint8_t i = 0; i < 41; i ++) {
           sc_setContainerSlot(client_fd, 0, serverSlotToClientSlot(i), player->inventory_count[i], player->inventory_items[i]);
diff --git a/src/tools.c b/src/tools.c
index 6cfdcad..fea00fe 100644
--- a/src/tools.c
+++ b/src/tools.c
@@ -7,6 +7,7 @@
 #include "globals.h"
 #include "varnum.h"
 #include "packets.h"
+#include "tools.h"
 
 static uint64_t htonll (uint64_t value) {
 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
@@ -144,9 +145,7 @@ int reservePlayerData (int client_fd, char *uuid) {
     if (empty) {
       player_data[i].client_fd = client_fd;
       memcpy(player_data[i].uuid, uuid, 16);
-      player_data[i].x = 8;
-      player_data[i].y = 80;
-      player_data[i].z = 8;
+      player_data[i].y = -32767;
       return 0;
     }
   }
diff --git a/src/worldgen.c b/src/worldgen.c
index 3249636..b85cb68 100644
--- a/src/worldgen.c
+++ b/src/worldgen.c
@@ -7,6 +7,7 @@
 #include "globals.h"
 #include "tools.h"
 #include "registries.h"
+#include "worldgen.h"
 
 uint32_t getHash (const void *data, size_t len) {
   const uint8_t *bytes = data;
@@ -50,8 +51,6 @@ int getCornerHeight (uint32_t hash) {
 
 }
 
-#define chunk_size 8
-
 int interpolate (int a, int b, int c, int d, int x, int z) {
   int top    = a * (chunk_size - x) + b * x;
   int bottom = c * (chunk_size - x) + d * x;
diff --git a/src/worldgen.h b/src/worldgen.h
index bbf374f..fe0e99d 100644
--- a/src/worldgen.h
+++ b/src/worldgen.h
@@ -3,7 +3,10 @@
 
 #include <stdint.h>
 
+#define chunk_size 8
+
+uint32_t getChunkHash (short x, short z);
+int getHeightAt (int rx, int rz, int _x, int _z, uint32_t chunk_hash);
 uint8_t getBlockAt (int x, int y, int z);
-void writeChunkSection (int client_fd, int _x, int _z, int i);
 
 #endif