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https://github.com/libretro/scummvm.git
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ec24687ce4
Adding @defgroup and @ingroup doxygen tags into all headers in the common folder that contain doxygen blocks. This improves the structure, readability, and findability of information in the resulting output. This commit targets purely structure and does not deal with the content of the currently existing doxygen documentation.
97 lines
2.2 KiB
C++
97 lines
2.2 KiB
C++
/* ScummVM - Graphic Adventure Engine
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*
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* ScummVM is the legal property of its developers, whose names
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* are too numerous to list here. Please refer to the COPYRIGHT
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* file distributed with this source distribution.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*
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*/
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// Based on eos' (I)FFT code which is in turn
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// based upon the (I)FFT code in FFmpeg
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// Copyright (c) 2008 Loren Merritt
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// Copyright (c) 2002 Fabrice Bellard
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// Partly based on libdjbfft by D. J. Bernstein
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#ifndef COMMON_FFT_H
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#define COMMON_FFT_H
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#include "common/scummsys.h"
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#include "common/math.h"
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namespace Common {
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/**
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* @defgroup common_fft Fast Fourier Transform (FFT)
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* @ingroup common
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*
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* @brief API for the FFT algorithm.
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*
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* @{
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*/
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class CosineTable;
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/**
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* (Inverse) Fast Fourier Transform
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*
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* Used in engines:
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* - scumm
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*/
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class FFT {
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public:
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FFT(int bits, int inverse);
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~FFT();
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const uint16 *getRevTab() const;
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/** Do the permutation needed BEFORE calling calc(). */
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void permute(Complex *z);
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/** Do a complex FFT.
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*
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* The input data must be permuted before.
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* No 1.0/sqrt(n) normalization is done.
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*/
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void calc(Complex *z);
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private:
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int _bits;
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int _inverse;
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uint16 *_revTab;
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Complex *_expTab;
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Complex *_tmpBuf;
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int _splitRadix;
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static int splitRadixPermutation(int i, int n, int inverse);
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CosineTable *_cosTables[13];
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void fft4(Complex *z);
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void fft8(Complex *z);
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void fft16(Complex *z);
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void fft(int n, int logn, Complex *z);
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};
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/** @} */
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} // End of namespace Common
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#endif // COMMON_FFT_H
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