3 files changed, 35 insertions, 5 deletions

diff --git a/glview.cc b/glview.cc
index 3d25f25..eaf061e 100644
--- a/glview.cc
+++ b/glview.cc
@@ -35,6 +35,8 @@ GLView::GLView(QWidget *parent) : QGLWidget(parent)
 	last_mouse_x = 0;
 	last_mouse_y = 0;
 
+	orthomode = false;
+
 	renderfunc = NULL;
 	renderfunc_vp = NULL;
 
@@ -168,7 +170,12 @@ void GLView::paintGL()
 
 	glMatrixMode(GL_PROJECTION);
 	glLoadIdentity();
-	glFrustum(-w_h_ratio, +w_h_ratio, -(1/w_h_ratio), +(1/w_h_ratio), +10.0, +FAR_FAR_AWAY);
+	if (orthomode)
+		glOrtho(-w_h_ratio*viewer_distance/10, +w_h_ratio*viewer_distance/10,
+				-(1/w_h_ratio)*viewer_distance/10, +(1/w_h_ratio)*viewer_distance/10,
+				-FAR_FAR_AWAY, +FAR_FAR_AWAY);
+	else
+		glFrustum(-w_h_ratio, +w_h_ratio, -(1/w_h_ratio), +(1/w_h_ratio), +10.0, +FAR_FAR_AWAY);
 	gluLookAt(0.0, -viewer_distance, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0);
 
 	glMatrixMode(GL_MODELVIEW);
diff --git a/mainwin.cc b/mainwin.cc
index 564a5a1..4a79de4 100644
--- a/mainwin.cc
+++ b/mainwin.cc
@@ -172,9 +172,12 @@ MainWindow::MainWindow(const char *filename)
 		menu->addAction("Front", this, SLOT(viewAngleFront()));
 		menu->addAction("Back", this, SLOT(viewAngleBack()));
 		menu->addAction("Diagonal", this, SLOT(viewAngleDiagonal()));
+
 		menu->addSeparator();
-		menu->addAction("Perspective");
-		menu->addAction("Orthogonal");
+		actViewPerspective = menu->addAction("Perspective", this, SLOT(viewPerspective()));
+		actViewPerspective->setCheckable(true);
+		actViewOrthogonal = menu->addAction("Orthogonal", this, SLOT(viewOrthogonal()));
+		actViewOrthogonal->setCheckable(true);
 	}
 
 	console->setReadOnly(true);
@@ -205,6 +208,7 @@ MainWindow::MainWindow(const char *filename)
 #else
 	viewModeThrownTogether();
 #endif
+	viewPerspective();
 
 	setCentralWidget(s1);
 	current_win = NULL;
@@ -1173,3 +1177,19 @@ void MainWindow::viewAngleDiagonal()
 	screen->updateGL();
 }
 
+void MainWindow::viewPerspective()
+{
+	actViewPerspective->setChecked(true);
+	actViewOrthogonal->setChecked(false);
+	screen->orthomode = false;
+	screen->updateGL();
+}
+
+void MainWindow::viewOrthogonal()
+{
+	actViewPerspective->setChecked(false);
+	actViewOrthogonal->setChecked(true);
+	screen->orthomode = true;
+	screen->updateGL();
+}
+
diff --git a/openscad.h b/openscad.h
index 0088723..b12e901 100644
--- a/openscad.h
+++ b/openscad.h
@@ -644,6 +644,7 @@ public:
 	void (*renderfunc)(void*);
 	void *renderfunc_vp;
 
+	bool orthomode;
 	double viewer_distance;
 	double object_rot_y;
 	double object_rot_z;
@@ -751,6 +752,8 @@ public:
 	QAction *actViewModeThrownTogether;
 	QAction *actViewModeShowEdges;
 	QAction *actViewModeAnimate;
+	QAction *actViewPerspective;
+	QAction *actViewOrthogonal;
 	void viewModeActionsUncheck();
 
 private slots:
@@ -764,8 +767,6 @@ private slots:
 	void viewModeThrownTogether();
 	void viewModeShowEdges();
 	void viewModeAnimate();
-
-private slots:
 	void viewAngleTop();
 	void viewAngleBottom();
 	void viewAngleLeft();
@@ -773,6 +774,8 @@ private slots:
 	void viewAngleFront();
 	void viewAngleBack();
 	void viewAngleDiagonal();
+	void viewPerspective();
+	void viewOrthogonal();
 };
 
 extern AbstractModule *parse(const char *text, int debug);