purezen 0.0.2

Runtime for the Pure Data (Pd) audio programming language, implemented as an extensible audio library allowing full control over signal processing, message passing, and graph manipulation. Pure Data is a graph-based programming language environment creating interactive music and multimedia works.
Documentation
/*
 *  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/>.
 *
 */

#ifndef _DSP_VCF_H_
#define _DSP_VCF_H_

#include "DspObject.h"

/** [vcf~], a voltage controlled bandpass filter */
class DspVCF : public DspObject {
  
  public:
    static MessageObject *new_object(PdMessage *init_message, PdGraph *graph);
    DspVCF(PdMessage *init_message, PdGraph *graph);
    ~DspVCF();
  
    static const char *get_object_label();
    std::string toString();
    
  private:
    void process_message(int inlet_index, PdMessage *message);
    void processDspWithIndex(int fromIndex, int toIndex);
  
    void calculateFilterCoefficients(float f, float q);
    float sigbp_qcos(float f); // not entirely sure what this is doing. From Pd.
    
    float sample_rate;
    float centerFrequency;
    float q;
    float coef1;
    float coef2;
    float gain;
    float tap_0;
    float tap_1;
};

inline std::string DspVCF::toString() {
  return DspVCF::get_object_label();
}

#endif // _DSP_VCF_H_