Mercurial > hg > beaglert
diff examples/10-Instruments/airharp/Junction.cpp @ 464:8fcfbfb32aa0 prerelease
Examples reorder with subdirectories. Added header to each project. Moved Doxygen to bottom of render.cpp.
author | Robert Jack <robert.h.jack@gmail.com> |
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date | Mon, 20 Jun 2016 16:20:38 +0100 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/examples/10-Instruments/airharp/Junction.cpp Mon Jun 20 16:20:38 2016 +0100 @@ -0,0 +1,95 @@ +/* + * + * Excitation Junction for two waveguides + * + * Christian Heinrichs 04/2015 + * + */ + +#include "Junction.h" +#include "../include/Utilities.h" + +Junction::Junction() { + + setFrequency(440); + _dt = 1.0/44100.0; + + // initialize variables + for(int i=0;i<WG_BUFFER_SIZE;i++) { + _buffer_l[i] = 0; + _buffer_r[i] = 0; + } + _excitation = 0; + _lastPlectrumDisplacement = 0; + _readPtr = 0; + +} + +void Junction::update(float excitation, float left, float right) { + + // 1. advance delay buffer read pointer + + if(++_readPtr>=WG_BUFFER_SIZE) + _readPtr=0; + + // 2. add excitation sample into buffer + + _buffer_l[(_readPtr+_delay_l+WG_BUFFER_SIZE)%WG_BUFFER_SIZE] = excitation; + _buffer_r[(_readPtr+_delay_r+WG_BUFFER_SIZE)%WG_BUFFER_SIZE] = excitation; + + // 3. feed right input to left output and vice versa + + _buffer_l[_readPtr] += right; + _buffer_r[_readPtr] += left; + + // 4. store excitation value for later use + _excitation = excitation; + +} + +float Junction::getOutput(int direction) { + + if(direction = 0) + return _buffer_l[_readPtr]; + else + return _buffer_r[_readPtr]; + +} + +float Junction::getExcitationDisplacement() { + + // string displacement and excitation force + // use delayed value to account for excitation position + float in = _buffer_l[(_readPtr+_delay_l+WG_BUFFER_SIZE)%WG_BUFFER_SIZE] + _excitation; + + // integrate total force + float out = 0.00001 * in + 0.99999 * _lastPlectrumDisplacement; + + // store variable for next iteration + _lastPlectrumDisplacement = out; + + // multiply by delta time + return out * _dt; + +} + +void Junction::setPluckPosition(float pluckPos){ + + pluckPos = constrain(pluckPos,0,1); + _delay_l = pluckPos * _periodInSamples; + _delay_r = (1-pluckPos) * _periodInSamples; + +} + +void Junction::setPeriod(float period) { + + _periodInMilliseconds = period; + +} + +void Junction::setFrequency(float frequency) { + + _periodInMilliseconds = 1000.0/frequency; + _periodInSamples = (int)(_periodInMilliseconds * 44.1); + +}