ExportProjectDialog: added option for exporting song as loop

This patch adds the option to remove the extra silence at the end,
so that the exported song can be seamlessly looped.

Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com>

src/core/song.cpp

@@ -82,6 +82,7 @@ song::song() :
 	m_modified( false ),
 	m_recording( false ),
 	m_exporting( false ),
+	m_export_loop( false ),
 	m_playing( false ),
 	m_paused( false ),
 	m_loadingProject( false ),
@@ -638,6 +639,7 @@ void song::stopExport()
 {
 	stop();
 	m_exporting = false;
+	m_export_loop = false;
 }
 
 

src/gui/ExportProjectDialog.cpp

@@ -27,6 +27,7 @@
 
 #include "ExportProjectDialog.h"
 #include "engine.h"
+#include "song.h"
 #include "MainWindow.h"
 #include "ProjectRenderer.h"
 #include "ui_ExportProjectDialog.h"
@@ -161,6 +162,8 @@ void ExportProjectDialog::startBtnClicked()
 		ui->bitrateCB->currentText().section( " ", 0, 0 ).toUInt(),
 		static_cast<ProjectRenderer::Depths>( ui->depthCB->currentIndex() ) );
 
+	engine::getSong()->setExportLoop( ui->exportLoopCB->isChecked() );
+
 	m_renderer = new ProjectRenderer( qs, es, ft, m_fileName );
 	if( m_renderer->isReady() )
 	{

src/gui/Forms/ExportProjectDialog.ui

@@ -284,6 +284,13 @@
           </item>
          </widget>
         </item>
+        <item>
+         <widget class="QCheckBox" name="exportLoopCB">
+          <property name="text">
+           <string>Export as loop (remove end silence)</string>
+          </property>
+         </widget>
+        </item>
         <item>
          <widget class="QCheckBox" name="sampleExactControllersCB">
           <property name="text">