diff --git a/libs/geom/include/psemek/geom/camera.hpp b/libs/geom/include/psemek/geom/camera.hpp
index 08cf74f0..8008967f 100644
--- a/libs/geom/include/psemek/geom/camera.hpp
+++ b/libs/geom/include/psemek/geom/camera.hpp
@@ -24,6 +24,8 @@ namespace psemek::geom
 		virtual vector<float, 3> axis_y() const;
 		virtual vector<float, 3> axis_z() const;
 
+		virtual vector<float, 3> direction() const;
+
 		// x, y are in clip-space [-1, 1]
 		// NB: this vector is not necessarily normalized
 		virtual vector<float, 3> direction(float x, float y) const;
diff --git a/libs/geom/source/camera.cpp b/libs/geom/source/camera.cpp
index cb433bc8..45e31eb2 100644
--- a/libs/geom/source/camera.cpp
+++ b/libs/geom/source/camera.cpp
@@ -46,6 +46,11 @@ namespace psemek::geom
 		return { b[0], b[1], b[2] };
 	}
 
+	vector<float, 3> camera::direction() const
+	{
+		return -axis_z();
+	}
+
 	vector<float, 3> camera::direction(float x, float y) const
 	{
 		vector<float, 4> b{ x, y, -1.f, 1.f};