diff --git a/src/MainWindow.h b/src/MainWindow.h
index b6eab9f8..71eadc15 100644
--- a/src/MainWindow.h
+++ b/src/MainWindow.h
@@ -86,6 +86,7 @@ private:
 	void openFile(const QString &filename);
         void handleFileDrop(const QString &filename);
 	void refreshDocument();
+        void updateCamera();
 	void updateTemporalVariables();
 	bool fileChangedOnDisk();
 	void compileTopLevelDocument();
diff --git a/src/builtin.cc b/src/builtin.cc
index fc43b5e4..c20f9f03 100644
--- a/src/builtin.cc
+++ b/src/builtin.cc
@@ -106,6 +106,7 @@ Builtins::Builtins()
 	Value zero3val(zero3);
 	this->globalscope.assignments.push_back(Assignment("$vpt", boost::shared_ptr<Expression>(new Expression(zero3val))));
 	this->globalscope.assignments.push_back(Assignment("$vpr", boost::shared_ptr<Expression>(new Expression(zero3val))));
+	this->globalscope.assignments.push_back(Assignment("$vpd", boost::shared_ptr<Expression>(new Expression(500))));
 }
 
 Builtins::~Builtins()
diff --git a/src/highlighter.cc b/src/highlighter.cc
index 955911d5..67c343e2 100644
--- a/src/highlighter.cc
+++ b/src/highlighter.cc
@@ -225,7 +225,7 @@ Highlighter::Highlighter(QTextDocument *parent)
 	tokentypes["prim3d"] << "cube" << "cylinder" << "sphere" << "polyhedron";
 	tokentypes["prim2d"] << "square" << "polygon" << "circle";
 	tokentypes["import"] << "include" << "use" << "import_stl" << "import" << "import_dxf" << "dxf_dim" << "dxf_cross" << "surface";
-	tokentypes["special"] << "$children" << "child" << "children" << "$fn" << "$fa" << "$fs" << "$t" << "$vpt" << "$vpr";
+	tokentypes["special"] << "$children" << "child" << "children" << "$fn" << "$fa" << "$fs" << "$t" << "$vpt" << "$vpr" << "$vpd";
 	tokentypes["extrude"] << "linear_extrude" << "rotate_extrude";
 	tokentypes["bracket"] << "[" << "]" << "(" << ")";
 	tokentypes["curlies"] << "{" << "}";
diff --git a/src/mainwin.cc b/src/mainwin.cc
index b028cb8f..d56177fa 100644
--- a/src/mainwin.cc
+++ b/src/mainwin.cc
@@ -36,6 +36,7 @@
 #include "highlighter.h"
 #include "export.h"
 #include "builtin.h"
+#include "expression.h"
 #include "progress.h"
 #include "dxfdim.h"
 #include "AboutDialog.h"
@@ -1363,6 +1364,68 @@ void MainWindow::updateTemporalVariables()
 	vpr.push_back(Value(fmodf(360 - qglview->cam.object_rot.y(), 360)));
 	vpr.push_back(Value(fmodf(360 - qglview->cam.object_rot.z(), 360)));
 	top_ctx.set_variable("$vpr", Value(vpr));
+
+	top_ctx.set_variable("$vpd", Value(qglview->cam.viewer_distance));
+}
+
+
+/*!
+ * Update the viewport camera by evaluating the special variables. If they
+ * are assigned on top-level, the values are used to change the camera
+ * rotation, translation and distance. 
+ */
+void MainWindow::updateCamera()
+{
+	if (!root_module)
+		return;
+	
+	bool camera_set = false;
+	double tx = qglview->cam.object_trans.x();
+	double ty = qglview->cam.object_trans.y();
+	double tz = qglview->cam.object_trans.z();
+	double rx = qglview->cam.object_rot.x();
+	double ry = qglview->cam.object_rot.y();
+	double rz = qglview->cam.object_rot.z();
+	double d = qglview->cam.viewer_distance;
+	BOOST_FOREACH(const Assignment &a, root_module->scope.assignments) {
+		double x, y, z;
+		if ("$vpr" == a.first) {
+			const Value vpr = a.second.get()->evaluate(&top_ctx);
+			if (vpr.getVec3(x, y, z)) {
+				rx = x;
+				ry = y;
+				rz = z;
+				camera_set = true;
+			}
+		} else if ("$vpt" == a.first) {
+			const Value vpt = a.second.get()->evaluate(&top_ctx);
+			if (vpt.getVec3(x, y, z)) {
+				tx = x;
+				ty = y;
+				tz = z;
+				camera_set = true;
+			}
+		} else if ("$vpd" == a.first) {
+			const Value vpd = a.second.get()->evaluate(&top_ctx);
+			if (vpd.type() == Value::NUMBER) {
+				d = vpd.toDouble();
+				camera_set = true;
+			}
+		}
+	}
+
+	if (camera_set) {
+		std::vector<double> params;
+		params.push_back(tx);
+		params.push_back(ty);
+		params.push_back(tz);
+		params.push_back(rx);
+		params.push_back(ry);
+		params.push_back(rz);
+		params.push_back(d);
+		qglview->cam.setup(params);
+		qglview->updateGL();
+	}
 }
 
 /*!
@@ -1410,6 +1473,7 @@ void MainWindow::compileTopLevelDocument()
 														QFileInfo(this->fileName).absolutePath().toLocal8Bit(),
 														false);
 
+	updateCamera();
 }
 
 void MainWindow::checkAutoReload()