3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include "irrlichttypes.h"
27 * The position hashing is very messed up.
28 * It's a lot more complicated than it looks.
31 static inline s16 unsigned_to_signed(u16 i, u16 max_positive)
33 if (i < max_positive) {
36 return i - (max_positive * 2);
41 // Modulo of a negative number does not work consistently in C
42 static inline s64 pythonmodulo(s64 i, s16 mod)
47 return mod - ((-i) % mod);
51 s64 MapDatabase::getBlockAsInteger(const v3s16 &pos)
53 return (u64) pos.Z * 0x1000000 +
54 (u64) pos.Y * 0x1000 +
59 v3s16 MapDatabase::getIntegerAsBlock(s64 i)
62 pos.X = unsigned_to_signed(pythonmodulo(i, 4096), 2048);
63 i = (i - pos.X) / 4096;
64 pos.Y = unsigned_to_signed(pythonmodulo(i, 4096), 2048);
65 i = (i - pos.Y) / 4096;
66 pos.Z = unsigned_to_signed(pythonmodulo(i, 4096), 2048);