Use mln::math::pi instead of a local definition in Milena.

	* mln/algebra/quat.hh (mln::algebra::quat::set_unit): Here.

milena/ChangeLog

+2013-08-27  Roland Levillain  <roland@lrde.epita.fr>
+
+	Use mln::math::pi instead of a local definition in Milena.
+
+	* mln/algebra/quat.hh (mln::algebra::quat::set_unit): Here.
+
 2013-08-27  Roland Levillain  <roland@lrde.epita.fr>
 	Set mln::math::pi to 20 decimals.

milena/mln/algebra/quat.hh

-// Copyright (C) 2007, 2008, 2009, 2012 EPITA Research and Development
+// Copyright (C) 2007, 2008, 2009, 2012, 2013 EPITA Research and Development
 // Laboratory (LRDE)
 //
 // This file is part of Olena.
@@ -462,12 +462,9 @@ namespace mln
     inline
     void quat::set_unit(float theta, const algebra::vec<3,T>& uv)
     {
-      static const float pi = 3.14159265358979323846f;
-
-      mln_precondition(theta > - pi - mln_epsilon(float)
-		       && theta < pi + mln_epsilon(float));
+      mln_precondition(theta > - float(math::pi) - mln_epsilon(float)
+		       && theta < float(math::pi) + mln_epsilon(float));
       mln_precondition(about_equal(norm::l2(uv), 1.f));
-      (void) pi;
 
       this->v_[0] = std::cos(theta);
       float sint = std::sin(theta);