diff -r 880d3fe9ac7c -r 4a95c6b06ebe src/documentloader.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/documentloader.cpp	Sun Sep 06 01:22:25 2015 +0300
@@ -0,0 +1,160 @@
+/*
+ *  LDForge: LDraw parts authoring CAD
+ *  Copyright (C) 2013 - 2015 Teemu Piippo
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <QFile>
+#include "documentloader.h"
+#include "ldDocument.h"
+#include "ldObject.h"
+#include "mainwindow.h"
+#include "dialogs/openprogressdialog.h"
+
+DocumentLoader::DocumentLoader (bool onForeground, QObject *parent) :
+	QObject (parent),
+	m_warningCount (0),
+	m_isDone (false),
+	m_hasAborted (false),
+	m_isOnForeground (onForeground) {}
+
+bool DocumentLoader::hasAborted()
+{
+	return m_hasAborted;
+}
+
+bool DocumentLoader::isDone() const
+{
+	return m_isDone;
+}
+
+int DocumentLoader::progress() const
+{
+	return m_progress;
+}
+
+int DocumentLoader::warningCount() const
+{
+	return m_warningCount;
+}
+
+bool DocumentLoader::isOnForeground() const
+{
+	return m_isOnForeground;
+}
+
+const LDObjectList& DocumentLoader::objects() const
+{
+	return m_objects;
+}
+
+void DocumentLoader::read (QIODevice* fp)
+{
+	if (fp and fp->isOpen())
+	{
+		while (not fp->atEnd())
+			m_lines << QString::fromUtf8 (fp->readLine());
+	}
+}
+
+void DocumentLoader::start()
+{
+	m_isDone = false;
+	m_progress = 0;
+	m_hasAborted = false;
+
+	if (isOnForeground())
+	{
+		// Show a progress dialog if we're loading the main ldDocument.here so we can show progress updates and keep the
+		// WM posted that we're still here.
+		m_progressDialog = new OpenProgressDialog (g_win);
+		m_progressDialog->setNumLines (m_lines.size());
+		m_progressDialog->setModal (true);
+		m_progressDialog->show();
+		connect (this, SIGNAL (workDone()), m_progressDialog, SLOT (accept()));
+		connect (m_progressDialog, SIGNAL (rejected()), this, SLOT (abort()));
+	}
+	else
+		m_progressDialog = null;
+
+	// Begin working
+	work (0);
+}
+
+void DocumentLoader::work (int i)
+{
+	// User wishes to abort, so stop here now.
+	if (hasAborted())
+	{
+		for (LDObject* obj : m_objects)
+			obj->destroy();
+
+		m_objects.clear();
+		m_isDone = true;
+		return;
+	}
+
+	// Parse up to 200 lines per iteration
+	int max = i + 200;
+
+	for (; i < max and i < (int) m_lines.size(); ++i)
+	{
+		QString line = m_lines[i];
+
+		// Trim the trailing newline
+		while (line.endsWith ("\n") or line.endsWith ("\r"))
+			line.chop (1);
+
+		LDObject* obj = ParseLine (line);
+
+		// Check for parse errors and warn about them
+		if (obj->type() == OBJ_Error)
+		{
+			print ("Couldn't parse line #%1: %2", progress() + 1, static_cast<LDError*> (obj)->reason());
+			++m_warningCount;
+		}
+
+		m_objects << obj;
+	}
+
+	m_progress = i;
+
+	if (m_progressDialog)
+		m_progressDialog->setProgress (i);
+
+	if (i >= m_lines.size() - 1)
+	{
+		emit workDone();
+		m_isDone = true;
+	}
+	else
+	{
+		// If we have a dialog to show progress output to, we cannot just call work() again immediately as the dialog
+		// needs to be updated as well. Thus, we take a detour through the event loop by using the meta-object system.
+		//
+		// This terminates the loop here and control goes back to the function which called the file loader. It will
+		// keep processing the event loop until we're ready (see loadFileContents), thus the event loop will eventually
+		// catch the invokation we throw here and send us back.
+		if (isOnForeground())
+			QMetaObject::invokeMethod (this, "work", Qt::QueuedConnection, Q_ARG (int, i));
+		else
+			work (i);
+	}
+}
+
+void DocumentLoader::abort()
+{
+	m_hasAborted = true;
+}
\ No newline at end of file