Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Branch: hiddenAdd
Fetching contributors…

Cannot retrieve contributors at this time

93 lines (83 sloc) 2.927 kB
/*
* Copyright 2009,2011 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 "DspVCF.h"
#include "PdGraph.h"
MessageObject *DspVCF::newObject(PdMessage *initMessage, PdGraph *graph) {
return new DspVCF(initMessage, graph);
}
DspVCF::DspVCF(PdMessage *initMessage, PdGraph *graph) : DspObject(3, 3, 0, 2, graph) {
sampleRate = graph->getSampleRate();
calculateFilterCoefficients(this->sampleRate/2.0f, 1.0f); // initialise the filter completely open
tap_0 = tap_1 = 0.0f;
}
DspVCF::~DspVCF() {
// nothing to do
}
const char *DspVCF::getObjectLabel() {
return "vcf~";
}
void DspVCF::calculateFilterCoefficients(float f, float q) {
float r, oneminusr, omega;
if (f < 0.001f) f = 10.0f;
if (q < 0.0f) q = 0.0f;
this->centerFrequency = f;
this->q = q;
omega = f * (2.0f * M_PI) / sampleRate;
if (q < 0.001) oneminusr = 1.0f;
else oneminusr = omega/q;
if (oneminusr > 1.0f) oneminusr = 1.0f;
r = 1.0f - oneminusr;
coef1 = 2.0f * sigbp_qcos(omega) * r;
coef2 = - r * r;
gain = 2 * oneminusr * (oneminusr + r * omega);
}
float DspVCF::sigbp_qcos(float f) {
if (f >= -(0.5f * M_PI) && f <= (0.5f * M_PI)) {
float g = f*f;
return (((g*g*g * (-1.0f/720.0f) + g*g*(1.0f/24.0f)) - g*0.5) + 1);
} else {
return 0.0f;
}
}
void DspVCF::processMessage(int inletIndex, PdMessage *message) {
// not sure what the other inlets do wrt messages
if (inletIndex == 2) {
if (message->isFloat(0)) {
q = message->getFloat(0); // update the resonance (q)
}
}
}
void DspVCF::processDspWithIndex(int fromIndex, int toIndex) {
/*
for (int i = fromIndex; i < toIndex; i++) {
calculateFilterCoefficients(dspBufferAtInlet1[i], q);
dspBufferAtOutlet0[i] = dspBufferAtInlet0[i] + (coef1 * tap_0) + (coef2 * tap_1);
tap_1 = tap_0;
tap_0 = dspBufferAtOutlet0[i];
}
// dspBufferAtOutlet0[i] *= gain;
ArrayArithmetic::multiply(dspBufferAtOutlet0, gain, dspBufferAtOutlet0, fromIndex, toIndex);
*/
// NOTE(mhroth): This object is definitely not working properly. It outputs only zero.
ArrayArithmetic::fill(dspBufferAtOutlet[0], 0, fromIndex, toIndex);
}
Jump to Line
Something went wrong with that request. Please try again.