Don't try to craft a non-existent item

[dragonfireclient.git] / src / database.cpp

diff --git a/src/database.cpp b/src/database.cpp
index 771d9b9629cb75562a9c71261a03e637367835bf..12e0e1a0f9292ff4ac3f7591a29e9059d4cef4fe 100644 (file)
--- a/src/database.cpp
+++ b/src/database.cpp
@@ -1,50 +1,69 @@
-#include "map.h"
-#include "mapsector.h"
-#include "mapblock.h"
-#include "main.h"
-#include "filesys.h"
-#include "voxel.h"
-#include "porting.h"
-#include "mapgen.h"
-#include "nodemetadata.h"
-#include "settings.h"
-#include "log.h"
-#include "profiler.h"
-#include "nodedef.h"
-#include "gamedef.h"
-#include "util/directiontables.h"
-#include "rollback_interface.h"
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
 
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
 
 #include "database.h"
+#include "irrlichttypes.h"
+
 
-static s32 unsignedToSigned(s32 i, s32 max_positive)
+/****************
+ * Black magic! *
+ ****************
+ * The position hashing is very messed up.
+ * It's a lot more complicated than it looks.
+ */
+
+static inline s16 unsigned_to_signed(u16 i, u16 max_positive)
 {
-       if(i < max_positive)
+       if (i < max_positive) {
                return i;
-       else
-               return i - 2*max_positive;
+       }
+
+       return i - (max_positive * 2);
 }
 
-// modulo of a negative number does not work consistently in C
-static s64 pythonmodulo(s64 i, s64 mod)
+
+// Modulo of a negative number does not work consistently in C
+static inline s64 pythonmodulo(s64 i, s16 mod)
 {
-       if(i >= 0)
+       if (i >= 0) {
                return i % mod;
+       }
        return mod - ((-i) % mod);
 }
 
-long long Database::getBlockAsInteger(const v3s16 pos) {
-       return (unsigned long long)pos.Z*16777216 +
-               (unsigned long long)pos.Y*4096 + 
-               (unsigned long long)pos.X;
+
+s64 MapDatabase::getBlockAsInteger(const v3s16 &pos)
+{
+       return (u64) pos.Z * 0x1000000 +
+               (u64) pos.Y * 0x1000 +
+               (u64) pos.X;
 }
 
-v3s16 Database::getIntegerAsBlock(long long i) {
-       s32 x = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-       i = (i - x) / 4096;
-       s32 y = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-       i = (i - y) / 4096;
-       s32 z = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-       return v3s16(x,y,z);
+
+v3s16 MapDatabase::getIntegerAsBlock(s64 i)
+{
+       v3s16 pos;
+       pos.X = unsigned_to_signed(pythonmodulo(i, 4096), 2048);
+       i = (i - pos.X) / 4096;
+       pos.Y = unsigned_to_signed(pythonmodulo(i, 4096), 2048);
+       i = (i - pos.Y) / 4096;
+       pos.Z = unsigned_to_signed(pythonmodulo(i, 4096), 2048);
+       return pos;
 }
+