diff -r 918b6c0f8b5b -r ed9685f44ab3 src/gl/compiler.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gl/compiler.h	Sat Dec 14 22:36:06 2019 +0200
@@ -0,0 +1,62 @@
+/*
+ *  LDForge: LDraw parts authoring CAD
+ *  Copyright (C) 2013 - 2018 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/>.
+ */
+
+#pragma once
+#include "main.h"
+#include "gl/partrenderer.h"
+#include "gl/common.h"
+#include "types/boundingbox.h"
+#include <QMap>
+#include <QSet>
+
+namespace gl
+{
+	class Compiler;
+	class Renderer;
+}
+
+/*
+ * Compiles LDObjects into polygons for the GLRenderer to draw.
+ */
+class gl::Compiler : public QObject, protected QOpenGLFunctions
+{
+	Q_OBJECT
+public:
+	Compiler(Renderer* renderer);
+	~Compiler();
+	void initialize();
+	Point3D modelCenter();
+	void prepareVBO (int vbonum);
+	GLuint vbo (int vbonum) const;
+	int vboSize (int vbonum) const;
+	static int vboNumber (VboClass surface, VboSubclass complement);
+private:
+	struct ObjectVboData
+	{
+		QVector<GLfloat> data[gl::numVbos];
+	};
+	QMap<QPersistentModelIndex, ObjectVboData> m_objectInfo;
+	QSet<QPersistentModelIndex> m_staged; // Objects that need to be compiled
+	GLuint m_vbo[gl::numVbos];
+	bool m_vboChanged[gl::numVbos] = {true};
+	bool needBoundingBoxRebuild = true;
+	int m_vboSizes[gl::numVbos] = {0};
+};
+
+#define CHECK_GL_ERROR() { checkGLError(__FILE__, __LINE__); }
+void checkGLError (QString file, int line);