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

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

+/*
+ *
+ * Plectrum model for touching and plucking strings
+ *
+ * Christian Heinrichs 04/2015
+ *
+ * [inspired by E. Berdahl's pluck~ abstraction for the FireFader]
+ *
+ */
+
+#include "Plectrum.h"
+
+#include "../include/Utilities.h"
+#include <cmath>
+#include <stdio.h>
+#include <cstdlib>
+
+Plectrum::Plectrum()	{
+
+	_contact = 0;
+	_lastDistance = 0;
+
+}
+
+void Plectrum::setup(float spring, float damp, float hyst)	{
+
+	_spring = spring;
+	_damp = damp;
+	_hyst = hyst;
+
+}
+
+float Plectrum::update(float position, float stringPosition)	{
+
+	float distance = position - stringPosition;
+
+	// Calculate spring/damp forces based on distance to string
+
+	float springOut = distance * _spring;
+
+	float dampOut = (distance - _lastDistance) * 44100;
+
+	float out = springOut+dampOut;
+
+	// If distance crosses zero, enable contact
+
+	if((distance>0 && _lastDistance<=0)||(distance<0 && _lastDistance>=0))
+		_contact = 1;
+
+	// If distance exceeds hysteresis threshold, jump to zero (i.e. 'pluck')
+
+	if(fabs(distance)>_hyst)
+		_contact = 0;
+
+	// FIXME: contact doesn't switch back to zero if distance goes back in original direction
+
+	_lastDistance = distance;
+
+	return out * _contact;
+
+}