From 7a7c9abd9b3913f2d805f99d4fa1be7d4ee23b17 Mon Sep 17 00:00:00 2001
From: Vesa <contact.diizy@nbl.fi>
Date: Thu, 20 Mar 2014 12:19:55 +0200
Subject: [PATCH] GraphModel: fix/improve normalize() function - remove bias
 before maximizing, also add some new slots for future use (which I plan to
 use for something neat in the future ;) )

---
 include/graph.h           | 20 +++++++-------
 src/gui/widgets/graph.cpp | 55 +++++++++++++++++++++++++++++++--------
 2 files changed, 55 insertions(+), 20 deletions(-)

diff --git a/include/graph.h b/include/graph.h
index 411224e1f..025e15a7b 100644
--- a/include/graph.h
+++ b/include/graph.h
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2006-2007 Andreas Brandmaier <andy/at/brandmaier/dot/de>
  *               2008 Paul Giblock <drfaygo/at/gmail/dot/com>
- * 
+ *
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
  * This program is free software; you can redistribute it and/or
@@ -24,8 +24,8 @@
  */
 
 
-#ifndef _GRAPH_H
-#define _GRAPH_H
+#ifndef GRAPH_H
+#define GRAPH_H
 
 #include <QtGui/QWidget>
 #include <QtGui/QPixmap>
@@ -71,7 +71,7 @@ public:
 	{
 		return m_graphStyle;
 	}
-	
+
 
 	inline void setGraphStyle( graphStyle _s )
 	{
@@ -101,10 +101,10 @@ private:
 
 	QPixmap m_foreground;
 	QColor m_graphColor;
-	
+
 	graphModel * m_graphModel;
 	graphStyle m_graphStyle;
-	
+
 	bool m_mouseDown;
 	int m_lastCursorX;
 
@@ -125,7 +125,7 @@ public:
 	virtual ~graphModel();
 
 	// TODO: saveSettings, loadSettings?
-	
+
 	inline float minValue() const
 	{
 		return( m_minValue );
@@ -140,7 +140,7 @@ public:
 	{
 		return( m_samples.count() );
 	}
-	
+
 	inline const float * samples() const
 	{
 		return( m_samples.data() );
@@ -160,10 +160,12 @@ public slots:
 	void setWaveToSquare();
 	void setWaveToNoise();
 	QString setWaveToUser( );
-	
+
 	void smooth();
 	void smoothNonCyclic();
 	void normalize();
+	void invert();
+	void shiftPhase( int _deg );
 
 signals:
 	void lengthChanged();
diff --git a/src/gui/widgets/graph.cpp b/src/gui/widgets/graph.cpp
index f336434fa..a7011537c 100644
--- a/src/gui/widgets/graph.cpp
+++ b/src/gui/widgets/graph.cpp
@@ -629,28 +629,61 @@ void graphModel::smoothNonCyclic()
 	emit samplesChanged(0, length()-1);
 }
 
+
+
 void graphModel::normalize()
 {
 	float max = 0.0001f;
+	float avg = 0.0f;
+
+	// first correct dc offset by normalizing to average
 	for( int i = 0; i < length(); i++ )
-	{
-		if( fabsf(m_samples[i]) > max && m_samples[i] != 0.0f )
-		{
-			max = fabs( m_samples[i] );
-		}
-	}
+		avg += m_samples[i];
+	avg /= length();
+	for( int i = 0; i < length(); i++ )
+		m_samples[i] -= avg;
+
+	// then maximize
+	for( int i = 0; i < length(); i++ )
+		max = qMax( max, qAbs( m_samples[i] ) );
 
 	for( int i = 0; i < length(); i++ )
-	{
-		m_samples[i] /= max;
-	}
+		m_samples[i] = qBound( m_minValue, m_samples[i] / max, m_maxValue );
 
-	if( max != 1.0f ) {
+	// signal changes if any
+	if( max != 1.0f || avg != 0.0f )
 		emit samplesChanged( 0, length()-1 );
-	}
 }
 
 
 
+void graphModel::invert()
+{
+	const float range = m_maxValue - m_minValue;
+
+	for( int i = 0; i < length(); i++ )
+		m_samples[i] = m_minValue + ( range - ( m_samples[i] - m_minValue ) );
+
+	emit samplesChanged( 0, length()-1 );
+}
+
+
+
+void graphModel::shiftPhase( int _deg )
+{
+	// calculate offset in samples
+	int offset = ( _deg * length() ) / 360; //multiply first because integers 
+	
+	// store values in temporary array
+	QVector<float> temp = m_samples;
+	
+	// shift phase
+	for( int i = 0; i < length(); i++ )
+		m_samples[i] = temp[ ( i + offset ) % length() ];
+	
+	emit samplesChanged( 0, length()-1 );
+}
+
+
 
 #include "moc_graph.cxx"