1 files changed, 100 insertions, 0 deletions
diff --git a/source/blender/freestyle/intern/geometry/normal_cycle.cpp b/source/blender/freestyle/intern/geometry/normal_cycle.cpp
new file mode 100644
index 00000000000..2f0aa268c9f
--- /dev/null
+++ b/source/blender/freestyle/intern/geometry/normal_cycle.cpp
@@ -0,0 +1,100 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * This Code is Copyright (C) 2010 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is:
+ *   OGF/Graphite: Geometry and Graphics Programming Library + Utilities
+ *   Copyright (C) 2000 Bruno Levy
+ *   Contact: Bruno Levy
+ *      levy@loria.fr
+ *      ISA Project
+ *      LORIA, INRIA Lorraine, 
+ *      Campus Scientifique, BP 239
+ *      54506 VANDOEUVRE LES NANCY CEDEX 
+ *      FRANCE
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/freestyle/intern/geometry/normal_cycle.cpp
+ *  \ingroup freestyle
+ *  \author Bruno Levy
+ */
+
+#include "matrix_util.h"
+#include "normal_cycle.h"
+
+namespace OGF {
+
+//_________________________________________________________
+
+
+NormalCycle::NormalCycle()
+{
+}
+
+void NormalCycle::begin()
+{
+	M_[0] = M_[1] = M_[2] = M_[3] = M_[4] = M_[5] = 0;
+}
+
+void NormalCycle::end()
+{
+	double eigen_vectors[9];
+	MatrixUtil::semi_definite_symmetric_eigen(M_, 3, eigen_vectors, eigen_value_);
+
+	axis_[0] = Vec3r(eigen_vectors[0], eigen_vectors[1], eigen_vectors[2]);
+
+	axis_[1] = Vec3r(eigen_vectors[3], eigen_vectors[4], eigen_vectors[5]);
+
+	axis_[2] = Vec3r(eigen_vectors[6], eigen_vectors[7], eigen_vectors[8]);
+
+	// Normalize the eigen vectors
+	for (int i = 0; i < 3; i++) {
+		axis_[i].normalize();
+	}
+
+	// Sort the eigen vectors
+	i_[0] = 0;
+	i_[1] = 1;
+	i_[2] = 2;
+
+	double l0 = ::fabs(eigen_value_[0]);
+	double l1 = ::fabs(eigen_value_[1]);
+	double l2 = ::fabs(eigen_value_[2]);
+
+	if (l1 > l0) {
+		ogf_swap(l0   , l1   );
+		ogf_swap(i_[0], i_[1]);
+	}
+	if (l2 > l1) {
+		ogf_swap(l1   , l2   );
+		ogf_swap(i_[1], i_[2]);
+	}
+	if (l1 > l0) {
+		ogf_swap(l0   , l1   );
+		ogf_swap(i_[0], i_[1]);
+	}
+}
+
+//_________________________________________________________
+
+}  // OGF namespace