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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.
*
*/
#ifndef COMMON_COSINETABLES_H
#define COMMON_COSINETABLES_H
namespace Common {
class CosineTable {
public:
/**
* Construct a cosine table given the number of points
*
* @param nPoints Number of distinct radian points, which must be in range [16,65536] and be divisible by 4
*/
CosineTable(int nPoints);
~CosineTable();
/**
* Get pointer to table.
*
* This table contains nPoints/2 entries.
* Prefer to use at()
* The layout of this table is as follows:
* - Entries 0 up to (including) nPoints/4:
* cos(0) till (including) cos(1/2*pi)
* - Entries (excluding) nPoints/4 up to nPoints/2:
* (excluding) cos(3/2*pi) till (excluding) cos(2*pi)
*/
const float *getTable() { return _tableEOS; }
/**
* Returns cos(2*pi * index / nPoints )
* Index must be in range [0, nPoints - 1]
* Faster than atLegacy
*/
float at(int index) const;
/**
* Returns cos(2*pi * index / nPoints )
* Index must be in range [0, nPoints - 1]
*/
float atLegacy(int index) const;
private:
float *_tableEOS;
float *_table;
double _radResolution; // Smallest radian increment
int _refSize; // _nPoints / 4
int _nPoints; // range of operator[]
};
} // End of namespace Common
#endif // COMMON_COSINETABLES_H
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