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/*
* Copyright 2009,2010,2011,2012 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/>.
*
*/
#ifndef _DSP_LOG_H_
#define _DSP_LOG_H_
#include "DspObject.h"
/** [log~], [log~ float] */
class DspLog : public DspObject {
public:
static MessageObject *new_object(PdMessage *init_message, PdGraph *graph);
DspLog(PdMessage *init_message, PdGraph *graph);
~DspLog();
static const char *get_object_label();
std::string toString();
void onInletConnectionUpdate(unsigned int inlet_index);
private:
static void processSignal(DspObject *dspObject, int fromIndex, int toIndex);
static void processScalar(DspObject *dspObject, int fromIndex, int toIndex);
void process_message(int inlet_index, PdMessage *message);
// this implementation is reproduced from http://www.musicdsp.org/showone.php?id=91
inline float log2Approx(float x) {
int y = (*(int *)&x); // input is assumed to be positive
return (((y & 0x7f800000)>>23)-0x7f)+(y & 0x007fffff)/(float)0x800000;
}
float invLog2Base; // 1/log2(base)
};
inline std::string DspLog::toString() {
return DspLog::get_object_label();
}
inline const char *DspLog::get_object_label() {
return "log~";
}
#endif // _DSP_LOG_H_