mirror of
https://github.com/dhewm/dhewm3.git
synced 2024-11-23 21:02:11 +00:00
155 lines
4.1 KiB
C++
155 lines
4.1 KiB
C++
/*
|
|
===========================================================================
|
|
|
|
Doom 3 GPL Source Code
|
|
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
|
|
|
|
This file is part of the Doom 3 GPL Source Code ("Doom 3 Source Code").
|
|
|
|
Doom 3 Source Code is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
Doom 3 Source Code 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
|
|
|
|
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
|
|
|
|
===========================================================================
|
|
*/
|
|
|
|
#include "../precompiled.h"
|
|
#pragma hdrstop
|
|
|
|
int idHashIndex::INVALID_INDEX[1] = { -1 };
|
|
|
|
/*
|
|
================
|
|
idHashIndex::Init
|
|
================
|
|
*/
|
|
void idHashIndex::Init( const int initialHashSize, const int initialIndexSize ) {
|
|
assert( idMath::IsPowerOfTwo( initialHashSize ) );
|
|
|
|
hashSize = initialHashSize;
|
|
hash = INVALID_INDEX;
|
|
indexSize = initialIndexSize;
|
|
indexChain = INVALID_INDEX;
|
|
granularity = DEFAULT_HASH_GRANULARITY;
|
|
hashMask = hashSize - 1;
|
|
lookupMask = 0;
|
|
}
|
|
|
|
/*
|
|
================
|
|
idHashIndex::Allocate
|
|
================
|
|
*/
|
|
void idHashIndex::Allocate( const int newHashSize, const int newIndexSize ) {
|
|
assert( idMath::IsPowerOfTwo( newHashSize ) );
|
|
|
|
Free();
|
|
hashSize = newHashSize;
|
|
hash = new int[hashSize];
|
|
memset( hash, 0xff, hashSize * sizeof( hash[0] ) );
|
|
indexSize = newIndexSize;
|
|
indexChain = new int[indexSize];
|
|
memset( indexChain, 0xff, indexSize * sizeof( indexChain[0] ) );
|
|
hashMask = hashSize - 1;
|
|
lookupMask = -1;
|
|
}
|
|
|
|
/*
|
|
================
|
|
idHashIndex::Free
|
|
================
|
|
*/
|
|
void idHashIndex::Free( void ) {
|
|
if ( hash != INVALID_INDEX ) {
|
|
delete[] hash;
|
|
hash = INVALID_INDEX;
|
|
}
|
|
if ( indexChain != INVALID_INDEX ) {
|
|
delete[] indexChain;
|
|
indexChain = INVALID_INDEX;
|
|
}
|
|
lookupMask = 0;
|
|
}
|
|
|
|
/*
|
|
================
|
|
idHashIndex::ResizeIndex
|
|
================
|
|
*/
|
|
void idHashIndex::ResizeIndex( const int newIndexSize ) {
|
|
int *oldIndexChain, mod, newSize;
|
|
|
|
if ( newIndexSize <= indexSize ) {
|
|
return;
|
|
}
|
|
|
|
mod = newIndexSize % granularity;
|
|
if ( !mod ) {
|
|
newSize = newIndexSize;
|
|
} else {
|
|
newSize = newIndexSize + granularity - mod;
|
|
}
|
|
|
|
if ( indexChain == INVALID_INDEX ) {
|
|
indexSize = newSize;
|
|
return;
|
|
}
|
|
|
|
oldIndexChain = indexChain;
|
|
indexChain = new int[newSize];
|
|
memcpy( indexChain, oldIndexChain, indexSize * sizeof(int) );
|
|
memset( indexChain + indexSize, 0xff, (newSize - indexSize) * sizeof(int) );
|
|
delete[] oldIndexChain;
|
|
indexSize = newSize;
|
|
}
|
|
|
|
/*
|
|
================
|
|
idHashIndex::GetSpread
|
|
================
|
|
*/
|
|
int idHashIndex::GetSpread( void ) const {
|
|
int i, index, totalItems, *numHashItems, average, error, e;
|
|
|
|
if ( hash == INVALID_INDEX ) {
|
|
return 100;
|
|
}
|
|
|
|
totalItems = 0;
|
|
numHashItems = new int[hashSize];
|
|
for ( i = 0; i < hashSize; i++ ) {
|
|
numHashItems[i] = 0;
|
|
for ( index = hash[i]; index >= 0; index = indexChain[index] ) {
|
|
numHashItems[i]++;
|
|
}
|
|
totalItems += numHashItems[i];
|
|
}
|
|
// if no items in hash
|
|
if ( totalItems <= 1 ) {
|
|
delete[] numHashItems;
|
|
return 100;
|
|
}
|
|
average = totalItems / hashSize;
|
|
error = 0;
|
|
for ( i = 0; i < hashSize; i++ ) {
|
|
e = abs( numHashItems[i] - average );
|
|
if ( e > 1 ) {
|
|
error += e - 1;
|
|
}
|
|
}
|
|
delete[] numHashItems;
|
|
return 100 - (error * 100 / totalItems);
|
|
}
|