diff --git a/src/libpython/core.cpp b/src/libpython/core.cpp
index b0a570c8..083cae52 100644
--- a/src/libpython/core.cpp
+++ b/src/libpython/core.cpp
@@ -901,6 +901,7 @@ struct NativeBuffer {
 			case Bitmap::EUInt8:   result = bp::object(((uint8_t *) buf.ptr)[idx]); break;
 			case Bitmap::EUInt16:  result = bp::object(((uint16_t *) buf.ptr)[idx]); break;
 			case Bitmap::EUInt32:  result = bp::object(((uint32_t *) buf.ptr)[idx]); break;
+			case Bitmap::EFloat16: result = bp::object((float) ((half *) buf.ptr)[idx]); break;
 			case Bitmap::EFloat32: result = bp::object(((float *) buf.ptr)[idx]); break;
 			case Bitmap::EFloat64: result = bp::object(((double *) buf.ptr)[idx]); break;
 			default:
diff --git a/src/mtsgui/main.cpp b/src/mtsgui/main.cpp
index 334614b4..d8195cc5 100644
--- a/src/mtsgui/main.cpp
+++ b/src/mtsgui/main.cpp
@@ -163,7 +163,7 @@ void collect_zombies(int s) {
 #endif
 
 int main(int argc, char *argv[]) {
-	int retval;
+	int retval = -1;
 
 	/* Initialize the core framework */
 	Class::staticInitialization();
@@ -298,8 +298,8 @@ int main(int argc, char *argv[]) {
 #endif
 
 		mainWindow = new MainWindow();
-		mainWindow->initWorkers();
-		retval = app.exec();
+		if (mainWindow->initWorkersProcessArgv())
+			retval = app.exec();
 
 #if defined(MTS_HAS_BREAKPAD)
 	#if defined(__OSX__)
@@ -313,7 +313,6 @@ int main(int argc, char *argv[]) {
 		SLog(EWarn, "Critical exception during startup: %s", e.what());
 		QMessageBox::critical(NULL, QString("Critical exception"),
 			e.what(), QMessageBox::Ok);
-		retval = -1;
 	}
 	Statistics::getInstance()->printStats();
 
diff --git a/src/mtsgui/mainwindow.cpp b/src/mtsgui/mainwindow.cpp
index 2468fb82..9817f963 100644
--- a/src/mtsgui/mainwindow.cpp
+++ b/src/mtsgui/mainwindow.cpp
@@ -246,7 +246,8 @@ MainWindow::MainWindow(QWidget *parent) :
 MainWindow::~MainWindow() {
 	m_renderQueue->unregisterListener(m_renderListener);
 	ref<Scheduler> scheduler = Scheduler::getInstance();
-	scheduler->pause();
+	if (scheduler->isRunning())
+		scheduler->pause();
 	for (int i=0; i<m_connections.size(); ++i) {
 		ServerConnection &c = m_connections[i];
 		scheduler->unregisterWorker(c.worker);
@@ -259,10 +260,52 @@ MainWindow::~MainWindow() {
     delete ui;
 }
 
-void MainWindow::initWorkers() {
+bool MainWindow::initWorkersProcessArgv() {
 	QSettings settings;
-	ref<Scheduler> scheduler = Scheduler::getInstance();
+	QStringList args = qApp->arguments(), toBeLoaded;
 	int localWorkerCount = settings.value("localWorkers", getCoreCount()).toInt();
+	ref<Scheduler> scheduler = Scheduler::getInstance();
+
+	for (int i=1; i<args.count(); ++i) {
+		if (args[i].startsWith("-D")) {
+			QString value = args[i].mid(2);
+			if (value.length() == 0 && i+1<args.count())
+				value = args[++i];
+			QStringList list = value.split("=");
+			if (list.length() == 2)
+				m_parameters[list[0].toStdString()] = list[1].toStdString();
+		} else if (args[i].startsWith("-a")) {
+			ref<FileResolver> resolver = Thread::getThread()->getFileResolver();
+			QString value = args[i].mid(2);
+			if (value.length() == 0 && i+1<args.count())
+				value = args[++i];
+			resolver->appendPath(value.toStdString());
+		} else if (args[i].startsWith("-p")) {
+			QString value = args[i].mid(2);
+			if (value.length() == 0 && i+1<args.count())
+				value = args[++i];
+			bool ok = false;
+			unsigned int numCores = value.toUInt(&ok, 10);
+			if (ok)
+				localWorkerCount = numCores;
+		} else if (args[i] == "-h") {
+			cout <<  "Mitsuba version " << Version(MTS_VERSION).toStringComplete()
+				 << ", Copyright (c) " MTS_YEAR " Wenzel Jakob" << endl;
+			cout <<  "Usage: mtsgui [options] <One or more scene XML files>" << endl;
+			cout <<  "Options/Arguments:" << endl;
+			cout <<  "   -h          Display this help text" << endl << endl;
+			cout <<  "   -D key=val  Define a constant, which can referenced as \"$key\" in the scene" << endl << endl;
+			cout <<  "   -a p1;p2;.. Add one or more entries to the resource search path" << endl << endl;
+			cout <<  "   -p count    Override the detected number of processors." << endl << endl;
+			cout <<  " For documentation, please refer to http://www.mitsuba-renderer.org/docs.html" << endl;
+			return false;
+		} else if (args[i].startsWith("-")) {
+			cerr << "Unknown option \"" << args[i].toStdString() << "\"" << endl;
+		} else {
+			toBeLoaded.append(args[i]);
+		}
+	}
+
 	m_workerPriority = (Thread::EThreadPriority)
 		settings.value("workerPriority", (int) Thread::ELowPriority).toInt();
 	for (int i=0; i<localWorkerCount; ++i)
@@ -317,22 +360,12 @@ void MainWindow::initWorkers() {
 		scheduler->registerWorker(new LocalWorker(0, formatString("wrk%i", localWorkerCtr++), m_workerPriority));
 	}
 
-	QStringList args = qApp->arguments();
-	for (int i=1; i<args.count(); ++i) {
-		if (args[i].startsWith("-D")) {
-			QString value = args[i].mid(2);
-			if (value.length() == 0 && i+1<args.count())
-				value = args[++i];
-			QStringList list = value.split("=");
-			if (list.length() == 2)
-				m_parameters[list[0].toStdString()] = list[1].toStdString();
-			continue;
-		}
-		loadFile(args[i]);
-	}
+	for (int i=0; i<toBeLoaded.size(); ++i)
+		loadFile(toBeLoaded[i]);
 
 	scheduler->start();
 	raise();
+	return true;
 }
 
 
diff --git a/src/mtsgui/mainwindow.h b/src/mtsgui/mainwindow.h
index 2ec338d7..6ecdebbd 100644
--- a/src/mtsgui/mainwindow.h
+++ b/src/mtsgui/mainwindow.h
@@ -120,7 +120,7 @@ public:
 	void loadFile(QString filename);
 	void adjustSize();
 	bool isActive();
-	void initWorkers();
+	bool initWorkersProcessArgv();
 
 protected:
 	SceneContext *loadScene(const QString &filename);