From 8178009eb5c274c19f7717c4686cf0dbcf4db067 Mon Sep 17 00:00:00 2001
From: Louis-Joseph Fournier <louisjoseph.fournier@gmail.com>
Date: Thu, 14 Jan 2016 19:56:24 +0100
Subject: [PATCH] Player: limit maximum frequency depending to rate

---
 src/audio/FreqPlayer.cpp | 4 +++-
 src/audio/FreqPlayer.hpp | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/audio/FreqPlayer.cpp b/src/audio/FreqPlayer.cpp
index d98380c..292675d 100644
--- a/src/audio/FreqPlayer.cpp
+++ b/src/audio/FreqPlayer.cpp
@@ -27,6 +27,7 @@ template<typename sample_t> FreqPlayer<sample_t>::FreqPlayer(int _rate):
 {
 	k = K();
 	k_update = -1; // invalid: don't update
+	max_harmonic_freq = rate / 2;
 }
 
 template<typename sample_t> void FreqPlayer<sample_t>::Reset()
@@ -92,7 +93,8 @@ template<typename sample_t> sample_t FreqPlayer<sample_t>::AudioFrame()
 
 	case W_HARMONIC:
 		v = 0;
-		for (i = 1; i <= nb_harmonics; i++) v += sin(r * i) / i;
+		for (i = 1; i <= nb_harmonics; i++) if (freq * i < max_harmonic_freq)
+			v += sin(r * i) / i;
 		break;
 
 	default:
diff --git a/src/audio/FreqPlayer.hpp b/src/audio/FreqPlayer.hpp
index d19b867..571b1e3 100644
--- a/src/audio/FreqPlayer.hpp
+++ b/src/audio/FreqPlayer.hpp
@@ -46,6 +46,8 @@ template<typename sample_t> class FreqPlayer {
 	sample_t last_frame;
 	/// number of hamonics for waveforms (W_HARMONIC only)
 	int nb_harmonics = 5;
+	/// max harmonic to play given current frequency
+	double max_harmonic_freq;
 
 	/// return k computed
 	double K() const;