diff --git a/src/lua/LuaScriptInterface.cpp b/src/lua/LuaScriptInterface.cpp
index 7895311f2..d9afd3df4 100644
--- a/src/lua/LuaScriptInterface.cpp
+++ b/src/lua/LuaScriptInterface.cpp
@@ -2072,6 +2072,75 @@ int PartsClosure(lua_State *l)
 	return 0;
 }
 
+static int NeighboursClosure(lua_State *l)
+{
+	int cx = lua_tointeger(l, lua_upvalueindex(1));
+	int cy = lua_tointeger(l, lua_upvalueindex(2));
+	int rx = lua_tointeger(l, lua_upvalueindex(3));
+	int ry = lua_tointeger(l, lua_upvalueindex(4));
+	int t = lua_tointeger(l, lua_upvalueindex(5));
+	int x = lua_tointeger(l, lua_upvalueindex(6));
+	int y = lua_tointeger(l, lua_upvalueindex(7));
+	while (y <= cy + ry)
+	{
+		int px = x;
+		int py = y;
+		x += 1;
+		if (x > cx + rx)
+		{
+			x = cx - rx;
+			y += 1;
+		}
+		int r = luacon_sim->pmap[py][px];
+		if (!(r && (!t || TYP(r) == t))) // * If not [exists and is of the correct type]
+		{
+			r = 0;
+		}
+		if (!r)
+		{
+			r = luacon_sim->photons[py][px];
+			if (!(r && (!t || TYP(r) == t))) // * If not [exists and is of the correct type]
+			{
+				r = 0;
+			}
+		}
+		if (r)
+		{
+			lua_pushnumber(l, x);
+			lua_replace(l, lua_upvalueindex(6));
+			lua_pushnumber(l, y);
+			lua_replace(l, lua_upvalueindex(7));
+			lua_pushnumber(l, ID(r));
+			lua_pushnumber(l, px);
+			lua_pushnumber(l, py);
+			return 3;
+		}
+	}
+	return 0;
+}
+
+int LuaScriptInterface::simulation_neighbours(lua_State * l)
+{
+	int cx = luaL_checkint(l, 1);
+	int cy = luaL_checkint(l, 2);
+	int rx = luaL_optint(l, 3, 2);
+	int ry = luaL_optint(l, 4, 2);
+	int t = luaL_optint(l, 5, PT_NONE);
+	if (rx < 0 || ry < 0)
+	{
+		luaL_error(l, "Invalid radius");
+	}
+	lua_pushnumber(l, cx);
+	lua_pushnumber(l, cy);
+	lua_pushnumber(l, rx);
+	lua_pushnumber(l, ry);
+	lua_pushnumber(l, t);
+	lua_pushnumber(l, cx - rx);
+	lua_pushnumber(l, cy - ry);
+	lua_pushcclosure(l, NeighboursClosure, 7);
+	return 1;
+}
+
 int LuaScriptInterface::simulation_parts(lua_State *l)
 {
 	lua_pushnumber(l, 0);
@@ -2105,59 +2174,6 @@ int LuaScriptInterface::simulation_photons(lua_State * l)
 	return 1;
 }
 
-int NeighboursClosure(lua_State * l)
-{
-	int rx=lua_tointeger(l, lua_upvalueindex(1));
-	int ry=lua_tointeger(l, lua_upvalueindex(2));
-	int sx=lua_tointeger(l, lua_upvalueindex(3));
-	int sy=lua_tointeger(l, lua_upvalueindex(4));
-	int x=lua_tointeger(l, lua_upvalueindex(5));
-	int y=lua_tointeger(l, lua_upvalueindex(6));
-	int i = 0;
-	do
-	{
-		x++;
-		if(x>rx)
-		{
-			x=-rx;
-			y++;
-			if(y>ry)
-				return 0;
-		}
-		if(!(x || y) || sx+x<0 || sy+y<0 || sx+x>=XRES*CELL || sy+y>=YRES*CELL)
-		{
-			continue;
-		}
-		i=luacon_sim->pmap[y+sy][x+sx];
-		if(!i)
-			i=luacon_sim->photons[y+sy][x+sx];
-	} while(!TYP(i));
-	lua_pushnumber(l, x);
-	lua_replace(l, lua_upvalueindex(5));
-	lua_pushnumber(l, y);
-	lua_replace(l, lua_upvalueindex(6));
-	lua_pushnumber(l, ID(i));
-	lua_pushnumber(l, x+sx);
-	lua_pushnumber(l, y+sy);
-	return 3;
-}
-
-int LuaScriptInterface::simulation_neighbours(lua_State * l)
-{
-	int x=luaL_checkint(l, 1);
-	int y=luaL_checkint(l, 2);
-	int rx=luaL_optint(l, 3, 2);
-	int ry=luaL_optint(l, 4, 2);
-	lua_pushnumber(l, rx);
-	lua_pushnumber(l, ry);
-	lua_pushnumber(l, x);
-	lua_pushnumber(l, y);
-	lua_pushnumber(l, -rx-1);
-	lua_pushnumber(l, -ry);
-	lua_pushcclosure(l, NeighboursClosure, 6);
-	return 1;
-}
-
 int LuaScriptInterface::simulation_framerender(lua_State * l)
 {
 	if (lua_gettop(l) == 0)