From e63eaf90755fb880441f3472d04c8d2387795fbc Mon Sep 17 00:00:00 2001
From: Sebastian Hoogen <github@sebastianhoogen.de>
Date: Tue, 15 May 2012 18:01:15 +0200
Subject: [PATCH] add isNull() method to Rotation

---
 src/Base/RotationPy.xml    |  8 ++++++++
 src/Base/RotationPyImp.cpp | 11 +++++++++++
 2 files changed, 19 insertions(+)

diff --git a/src/Base/RotationPy.xml b/src/Base/RotationPy.xml
index 02dc34ee84..111cfb74c7 100644
--- a/src/Base/RotationPy.xml
+++ b/src/Base/RotationPy.xml
@@ -48,6 +48,14 @@
 				</UserDocu>
 			</Documentation>
 		</Methode>
+		<Methode Name="isNull">
+			<Documentation>
+				<UserDocu>
+					isNull() -> Bool
+					returns True if the rotation equals the unity matrix
+				</UserDocu>
+			</Documentation>
+		</Methode>
 		<Attribute Name="Q" ReadOnly="false">
 			<Documentation>
 				<UserDocu>The rotation elements (as quaternion)</UserDocu>
diff --git a/src/Base/RotationPyImp.cpp b/src/Base/RotationPyImp.cpp
index 7abede54c7..159952c7e0 100644
--- a/src/Base/RotationPyImp.cpp
+++ b/src/Base/RotationPyImp.cpp
@@ -144,6 +144,17 @@ PyObject* RotationPy::toEuler(PyObject * args)
     return Py::new_reference_to(tuple);
 }
 
+PyObject* RotationPy::isNull(PyObject *args)
+{
+    if (!PyArg_ParseTuple(args, ""))
+        return NULL;
+    Base::Rotation rot = * getRotationPtr();
+    Base::Rotation nullrot(0,0,0,1);
+    Base::Rotation nullrotinv(0,0,0,-1);
+    bool null = (rot == nullrot) | (rot == nullrotinv);
+    return Py_BuildValue("O", (null ? Py_True : Py_False));
+}
+
 Py::Tuple RotationPy::getQ(void) const
 {
     double q0, q1, q2, q3;