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diff --git a/muse2/plugins/doublechorus/simplechorusmodel.cpp b/muse2/plugins/doublechorus/simplechorusmodel.cpp
new file mode 100644
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+++ b/muse2/plugins/doublechorus/simplechorusmodel.cpp
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+//===========================================================================
+//
+//    simplechorus
+//
+//    Version 0.0.1
+//
+//
+//
+//
+//  Copyright (c) 2006 Nil Geisweiller
+//
+//
+//
+// 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., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA or point your web browser to http://www.gnu.org.
+//===========================================================================
+
+#include "simplechorusmodel.h"
+#include <math.h>
+#include <stdio.h>
+
+#define ABS(x) (x>=0?x:-x)
+
+// Linearly interpolate [ = a * (1 - f) + b * f]
+inline float lin_interp(float f, float a, float b) {
+  return a + f * (b - a);
+}
+
+// Cubic interpolation function
+inline float cube_interp(const float fr,
+			 const float inm1,
+			 const float in,
+			 const float inp1,
+			 const float inp2) {
+  return in + 0.5f * fr * (inp1 - inm1 +
+			   fr * (4.0f * inp1 + 2.0f * inm1 - 5.0f * in - inp2 +
+				 fr * (3.0f * (in - inp1) - inm1 + inp2)));
+}
+
+float SimpleChorusModel::sinus[MAXSINUSRESOLUTION];
+int SimpleChorusModel::useCount = 0;
+
+SimpleChorusModel::SimpleChorusModel(float samplerate) {
+  _sampleRate = samplerate;
+  //sinus
+  if (useCount++ == 0)
+    for(int i = 0; i < MAXSINUSRESOLUTION; i++)
+      sinus[i] = (float)(sin(((double)i * 2.0 * M_PI) /
+			      (double)MAXSINUSRESOLUTION));
+  _index = 0.0;
+  //init buffer
+  for(int i = 0; i < MAXBUFFERLENGTH; i++) {
+    _leftBuffer[i] = 0.0;
+    _rightBuffer[i] = 0.0;
+  }
+  _position = 0;
+  //initial parameters
+  _pan = 0.5;
+  _LFOFreq = 1.0;
+  _depth = 0.5;
+  setChorus();
+}
+
+SimpleChorusModel::~SimpleChorusModel() {
+}
+
+void SimpleChorusModel::process_chorus(float leftInput, float rightInput,
+				       float* leftOutput, float* rightOutput) {
+  float ocsDiff;
+
+  _ocsDistance = _depthAmp * sinus[(int)_index];
+  
+  ocsDiff = _ocsDistance - floorf(_ocsDistance);
+
+  _past_position_left = MAXBUFFERLENGTH //to be sure that _past_position_left>0
+    + _position - _leftMidDistance + (int)_ocsDistance;
+  _past_position_right = MAXBUFFERLENGTH
+    + _position - _rightMidDistance + (int)_ocsDistance;
+
+  *leftOutput = _leftAmp *
+    lin_interp(ocsDiff, _leftBuffer[_past_position_left%MAXBUFFERLENGTH],
+	       _leftBuffer[(_past_position_left+1)%MAXBUFFERLENGTH]);
+  *rightOutput = _rightAmp *
+    lin_interp(ocsDiff, _rightBuffer[_past_position_right%MAXBUFFERLENGTH],
+	       _rightBuffer[(_past_position_right+1)%MAXBUFFERLENGTH]);
+
+  _leftBuffer[_position] = leftInput;
+  _rightBuffer[_position] = rightInput;
+  
+  _position++;
+  _position %= MAXBUFFERLENGTH;
+  
+  _index += _inct;
+  _index = (_index<MAXSINUSRESOLUTION?_index:_index-MAXSINUSRESOLUTION);
+}
+
+void SimpleChorusModel::setPan(float p) {
+  _pan = p;
+  setChorus();
+}
+void SimpleChorusModel::setLFOFreq(float l) {
+  _LFOFreq = l;
+  setChorus();
+}
+void SimpleChorusModel::setDepth(float d) {
+  _depth = d;
+  setChorus();
+}
+void SimpleChorusModel::setSampleRate(float s) {
+  _sampleRate = s;
+  setChorus();
+}
+
+float SimpleChorusModel::getPan() {
+  return _pan;
+}
+float SimpleChorusModel::getLFOFreq() {
+  return _LFOFreq;
+}
+float SimpleChorusModel::getDepth() {
+  return _depth;
+}
+
+void SimpleChorusModel::setChorus() {
+  //inct
+  _inct = (float)MAXSINUSRESOLUTION/_sampleRate * _LFOFreq;
+  //left & right amp
+  _leftAmp = lin_interp(1.0 - _pan, 1.0 - PANAMP, 1.0 + PANAMP);
+  _rightAmp = lin_interp(_pan, 1.0 - PANAMP, 1.0 + PANAMP);
+  //left & right midDistance
+  float leftmdm; //left mid distance in meter
+  float rightmdm; //right mid distance in meter
+  leftmdm = MIDSOURCEDISTANCE - EARSDISTANCE * (0.5 - _pan);
+  rightmdm = MIDSOURCEDISTANCE + EARSDISTANCE * (0.5 - _pan);
+
+  _leftMidDistance = (int)(_sampleRate * leftmdm / SOUNDSPEED);
+  _rightMidDistance = (int)(_sampleRate * rightmdm / SOUNDSPEED);
+
+  //depthAmp
+  _depthAmp =
+    _sampleRate * (MAXDEPTH * _depth) /SOUNDSPEED;
+  //filter coef
+  _filterCoef1 = 1 - COEFFILTER;
+  _filterCoef2 = COEFFILTER;
+}