1 files changed, 53 insertions, 0 deletions
diff --git a/ep_positionconstraint_centered.py b/ep_positionconstraint_centered.py
new file mode 100644
index 0000000..12fd99c
--- /dev/null
+++ b/ep_positionconstraint_centered.py
@@ -0,0 +1,53 @@
+# coding: UTF8
+# Copyright 2009 Thomas Jourdan
+#
+# 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 3 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 St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import random
+import ka_random
+import model_locus
+
+class CenteredPositionConstraint(model_locus.Locus):
+    """CenteredPositionConstraint
+    """
+
+    def __init__(self, trunk):
+        """Position constraint constructor
+        """
+        super(CenteredPositionConstraint, self).__init__(trunk)
+        
+    def filter(self, x_pos, y_pos):
+        """Set constraint x- and y-position.
+        post: len(__return__) == 2
+        """
+        xp = (x_pos + 0.5) / 2.0
+        yp = (y_pos + 0.5) / 2.0
+        return xp, yp
+
+    def randomize(self):
+        """Set x- and y-position to random values.
+        post: len(__return__) == 2
+        """
+        return random.gauss(0.5, 0.1), random.gauss(0.5, 0.1)
+
+    def mutate(self, x_pos, y_pos):
+        """Make small random changes in x- and y-position.
+        post: len(__return__) == 2
+        """
+        xp = x_pos + ka_random.jitter(0.2)
+        xp = (2.0*xp + random.gauss(0.5, 0.1)) / 3.0
+        yp = y_pos + ka_random.jitter(0.2)
+        yp = (2.0*yp + random.gauss(0.5, 0.1)) / 3.0
+        return xp, yp