FXLine: add context menu with options to remove, move & rename FX channels

- Uses existing functionality in FxMixer & FxMixerView to manipulate channels
- Instruments sending to the manipulated channels get automatically updated
- In the future I hope to implement a drag/drop functionality instead of the clunky context menu but this is a good first step until then
- Also added in a little QWhatsThis help message for the FX line, also accessible from context menu

That lmms_math thing got mixed in accidentally, but it's also a good change: always include math.h in lmms_math - that way, other parts of the software can just #include lmms_math, and won't have to #include both math.h and lmms_math, also the yet unused sinc function in it seems to need it so this prevents problems down the line

include/FxLine.h

@@ -23,8 +23,8 @@
  *
  */
 
-#ifndef _FX_LINE_H
-#define _FX_LINE_H
+#ifndef FX_LINE_H
+#define FX_LINE_H
 
 #include <QWidget>
 #include <QLabel>
@@ -46,6 +46,7 @@ public:
 	virtual void paintEvent( QPaintEvent * );
 	virtual void mousePressEvent( QMouseEvent * );
 	virtual void mouseDoubleClickEvent( QMouseEvent * );
+	virtual void contextMenuEvent( QContextMenuEvent * );
 
 	inline int channelIndex() { return m_channelIndex; }
 	void setChannelIndex(int index);
@@ -56,11 +57,16 @@ public:
 private:
 	FxMixerView * m_mv;
 	LcdWidget* m_lcd;
-
-
 	int m_channelIndex;
 
-} ;
+private slots:
+	void renameChannel();
+	void removeChannel();
+	void moveChannelLeft();
+	void moveChannelRight();
+	void displayHelp();
+
+};
 
 
 #endif // FXLINE_H

include/lmms_math.h

@@ -29,10 +29,10 @@
 #include <stdint.h>
 #include "lmms_constants.h"
 
-#ifdef __INTEL_COMPILER
-
 #include <math.h>
 
+#ifdef __INTEL_COMPILER
+
 static inline float absFraction( const float _x )
 {
 	return( _x - ( _x >= 0.0f ? floorf( _x ) : floorf( _x ) - 1 ) );

src/gui/widgets/FxLine.cpp

@@ -29,6 +29,7 @@
 #include <QtGui/QInputDialog>
 #include <QtGui/QPainter>
 #include <QtGui/QLineEdit>
+#include <QtGui/QWhatsThis>
 
 #include "FxMixer.h"
 #include "FxMixerView.h"
@@ -36,6 +37,8 @@
 #include "engine.h"
 #include "SendButtonIndicator.h"
 #include "gui_templates.h"
+#include "caption_menu.h"
+
 
 FxLine::FxLine( QWidget * _parent, FxMixerView * _mv, int _channelIndex) :
 	QWidget( _parent ),
@@ -61,8 +64,23 @@ FxLine::FxLine( QWidget * _parent, FxMixerView * _mv, int _channelIndex) :
 	m_lcd->setValue( m_channelIndex );
 	m_lcd->move( 4, 58 );
 	m_lcd->setMarginWidth( 1 );
+	
+	setWhatsThis( tr(
+	"The FX channel receives input from one or more instrument tracks.\n "
+	"It in turn can be routed to multiple other FX channels. LMMS automatically "
+	"takes care of preventing infinite loops for you and doesn't allow making "
+	"a connection that would result in an infinite loop.\n\n"
+	
+	"In order to route the channel to another channel, select the FX channel "
+	"and click on the \"send\" button on the channel you want to send to. "
+	"The knob under the send button controls the level of signal that is sent "
+	"to the channel.\n\n"
+	
+	"You can remove and move FX channels in the context menu, which is accessed "
+	"by right-clicking the FX channel.\n") );
 }
 
+
 FxLine::~FxLine()
 {
 	delete m_sendKnob;
@@ -125,6 +143,7 @@ static void drawFxLine( QPainter* p, const QWidget *fxLine, const QString& name,
 
 }
 
+
 void FxLine::paintEvent( QPaintEvent * )
 {
 	FxMixer * mix = engine::fxMixer();
@@ -138,12 +157,47 @@ void FxLine::paintEvent( QPaintEvent * )
 	painter.end();
 }
 
+
 void FxLine::mousePressEvent( QMouseEvent * )
 {
 	m_mv->setCurrentFxLine( this );
 }
 
+
 void FxLine::mouseDoubleClickEvent( QMouseEvent * )
+{
+	renameChannel();
+}
+
+
+void FxLine::contextMenuEvent( QContextMenuEvent * )
+{
+	FxMixer * mix = engine::fxMixer();
+	QPointer<captionMenu> contextMenu = new captionMenu( mix->effectChannel( m_channelIndex )->m_name );
+	if( m_channelIndex != 0 ) // no move-options in master 
+	{
+		contextMenu->addAction( tr( "Move &left" ),	this, SLOT( moveChannelLeft() ) );
+		contextMenu->addAction( tr( "Move &right" ), this, SLOT( moveChannelRight() ) );
+	}
+	contextMenu->addAction( tr( "Rename &channel" ), this, SLOT( renameChannel() ) );
+	contextMenu->addSeparator();
+	
+	if( m_channelIndex != 0 ) // no remove-option in master
+	{
+		contextMenu->addAction( embed::getIconPixmap( "cancel" ), tr( "R&emove channel" ),
+							this, SLOT( removeChannel() ) );
+		contextMenu->addSeparator();
+	}
+	
+	contextMenu->addAction( embed::getIconPixmap( "help" ),
+						tr( "&Help" ),
+						this, SLOT( displayHelp() ) );
+	contextMenu->exec( QCursor::pos() );
+	delete contextMenu;
+}
+
+
+void FxLine::renameChannel()
 {
 	bool ok;
 	FxMixer * mix = engine::fxMixer();
@@ -154,10 +208,38 @@ void FxLine::mouseDoubleClickEvent( QMouseEvent * )
 			QLineEdit::Normal, mix->effectChannel(m_channelIndex)->m_name, &ok );
 	if( ok && !new_name.isEmpty() )
 	{
-		mix->effectChannel(m_channelIndex)->m_name = new_name;
+		mix->effectChannel( m_channelIndex )->m_name = new_name;
 		update();
 	}
 }
 
+
+void FxLine::removeChannel()
+{
+	FxMixerView * mix = engine::fxMixerView();
+	mix->deleteChannel( m_channelIndex );
+}
+
+
+void FxLine::moveChannelLeft()
+{
+	FxMixerView * mix = engine::fxMixerView();
+	mix->moveChannelLeft( m_channelIndex );
+}
+
+
+void FxLine::moveChannelRight()
+{
+	FxMixerView * mix = engine::fxMixerView();
+	mix->moveChannelRight( m_channelIndex );
+}
+
+
+void FxLine::displayHelp()
+{
+	QWhatsThis::showText( mapToGlobal( rect().bottomRight() ),
+								whatsThis() );
+}
+
 #include "moc_FxLine.cxx"