X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fdatabase.cpp;h=26f6992fcb47e7e84b5fad70707857fcaa1cd857;hb=b97c9c65777b0389f4cc9a6e3257506f29761e03;hp=b793cd2f29a3675c39c8ac7438e88e17e5fd0d64;hpb=95e4a93b1bb98eb94b4ca00fb73a0162bd5c8c0e;p=oweals%2Fminetest.git

diff --git a/src/database.cpp b/src/database.cpp
index b793cd2f2..26f6992fc 100644
--- a/src/database.cpp
+++ b/src/database.cpp
@@ -20,33 +20,50 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #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;
+	} else {
+		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 Database::getBlockAsInteger(const v3s16 pos) const
+{
+	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 Database::getIntegerAsBlock(s64 i) const
+{
+	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;
 }
+