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/*
* Copyright 2011,2012 Reality Jockey, Ltd.
* info@rjdj.me
* http://rjdj.me/
*
* This file is part of ZenGarden.
*
* ZenGarden is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* ZenGarden 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with ZenGarden. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "ArrayArithmetic.h"
#include "DspFilter.h"
class PdGraph;
DspFilter::DspFilter(int numMessageInlets, PdGraph *graph) : DspObject(numMessageInlets, 1, 0, 1, graph) {
x1 = x2 = y1 = y2 = 0.0f;
process_function = &processFilter;
process_functionNoMessage = &processFilter;
}
DspFilter::~DspFilter() {
// nothing to do
}
void DspFilter::onInletConnectionUpdate(unsigned int inlet_index) {
// TODO(mhroth)
}
void DspFilter::processFilter(DspObject *dspObject, int fromIndex, int toIndex) {
DspFilter *d = reinterpret_cast<DspFilter *>(dspObject);
int n = toIndex - fromIndex; // number of samples to process
float bufferIn[n+2]; // new inlet buffer
bufferIn[0] = d->x2; bufferIn[1] = d->x1;
memcpy(bufferIn+2, d->dspBufferAtInlet[0]+fromIndex, n*sizeof(float));
float bufferOut[n+2]; // new outlet buffer
bufferOut[0] = d->y2; bufferOut[1] = d->y1;
#if __APPLE__
vDSP_deq22(bufferIn, 1, d->b, bufferOut, 1, n);
#else
int _toIndex = n + 2;
for (int i = 2; i < _toIndex; ++i) {
bufferOut[i] = d->b[0]*bufferIn[i] + d->b[1]*bufferIn[i-1] + d->b[2]*bufferIn[i-2] -
d->b[3]*bufferOut[i-1] - d->b[4]*bufferOut[i-2];
}
#endif
memcpy(d->dspBufferAtOutlet[0]+fromIndex, bufferOut+2, n*sizeof(float));
// retain state
d->x2 = bufferIn[n]; d->x1 = bufferIn[n+1];
d->y2 = bufferOut[n]; d->y1 = bufferOut[n+1];
}