rename Placement.isNull to Placement.isIdentity

implement Rotation.isNull and Rotation.isIdentity

src/Base/PlacementPy.xml

@@ -76,10 +76,10 @@ Placement(Base, Axis, Angle) -- define position and rotation
 				</UserDocu>
 			</Documentation>
 		</Methode>
-        <Methode Name="isNull" Const="true">
+        <Methode Name="isIdentity" Const="true">
 			<Documentation>
 				<UserDocu>
-					isNull() -> Bool
+                    isIdentity() -> Bool
 					returns True if the placement has no displacement and no rotation
 				</UserDocu>
 			</Documentation>

src/Base/PlacementPyImp.cpp

@@ -200,16 +200,14 @@ PyObject* PlacementPy::inverse(PyObject * args)
     return new PlacementPy(new Placement(p));
 }
 
-PyObject* PlacementPy::isNull(PyObject *args)
+PyObject* PlacementPy::isIdentity(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
         return NULL;
+    Base::Vector3d nullvec(0,0,0);
     Base::Vector3d pos = getPlacementPtr()->getPosition();
     Base::Rotation rot = getPlacementPtr()->getRotation();
-    Base::Vector3d nullvec(0,0,0);
-    Base::Rotation nullrot(0,0,0,1);
-    Base::Rotation nullrotinv(0,0,0,-1);
-    bool null = (pos == nullvec) & ((rot == nullrot) | (rot == nullrotinv));
+    bool null = (pos == nullvec) && (rot.isIdentity());
     return Py_BuildValue("O", (null ? Py_True : Py_False));
 }
 

src/Base/Rotation.cpp

@@ -658,6 +658,15 @@ void Rotation::getYawPitchRoll(double& y, double& p, double& r) const
     r = (r/D_PI)*180;
 }
 
+bool Rotation::isIdentity() const
+{
+    return ((this->quat[0] == 0  &&
+             this->quat[1] == 0  &&
+             this->quat[2] == 0) &&
+            (this->quat[3] == 1 ||
+             this->quat[3] == -1);
+}
+
 bool Rotation::isNull() const
 {
     return (this->quat[0] == 0 &&

src/Base/Rotation.h

@@ -63,6 +63,7 @@ public:
     void setYawPitchRoll(double y, double p, double r);
     /// Euler angles in yaw,pitch,roll notation
     void getYawPitchRoll(double& y, double& p, double& r) const;
+    bool isIdentity() const;
     bool isNull() const;
     //@}
 

src/Base/RotationPy.xml

@@ -84,10 +84,18 @@
 			<Documentation>
 				<UserDocu>
 					isNull() -> Bool
-					returns True if the rotation equals the unity matrix
+                    returns True if all Q values are zero
 				</UserDocu>
 			</Documentation>
 		</Methode>
+        <Methode Name="isIdentity" Const="true">
+            <Documentation>
+                <UserDocu>
+                    isIdentity() -> 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>

src/Base/RotationPyImp.cpp

@@ -282,13 +282,19 @@ PyObject* RotationPy::isSame(PyObject *args)
     return Py_BuildValue("O", (same ? Py_True : Py_False));
 }
 
+PyObject* RotationPy::isIdentity(PyObject *args)
+{
+    if (!PyArg_ParseTuple(args, ""))
+        return NULL;
+    bool null = getRotationPtr()->isIdentity();
+    return Py_BuildValue("O", (null ? Py_True : Py_False));
+}
+
 PyObject* RotationPy::isNull(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
         return NULL;
-    Base::Rotation rot = * getRotationPtr();
-    Base::Rotation nullrot(0,0,0,1);
-    bool null = rot.isSame(nullrot);
+    bool null = getRotationPtr()->isNull();
     return Py_BuildValue("O", (null ? Py_True : Py_False));
 }