comparison projects/airharp/Junction.cpp @ 164:40badaff5729 heavy-updated

- added more pd/heavy examples
- removed heavy-specific flags from Makefile
- added air-harp cpp example project

+/*
+ *
+ * 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);
+
+}