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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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 2
* 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 General Public License for more details.
* You should have received a copy of the GNU 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.
*
*/
// Based on eos' sine tables
#include "common/scummsys.h"
#include "common/sinetables.h"
namespace Common {
SineTable::SineTable(int bitPrecision) {
assert((bitPrecision >= 4) && (bitPrecision <= 16));
_bitPrecision = bitPrecision;
int m = 1 << _bitPrecision;
double freq = 2 * M_PI / m;
_table = new float[m];
// Table contains sin(2*pi*x/n) for 0<=x<=n/4,
// followed by its reverse
for (int i = 0; i <= m / 4; i++)
_table[i] = sin(i * freq);
for (int i = 1; i < m / 4; i++)
_table[m / 2 - i] = _table[i];
}
SineTable::~SineTable() {
delete[] _table;
}
} // End of namespace Common
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