FEM: general python contraint, add module

src/Mod/Fem/App/CMakeLists.txt

@@ -92,6 +92,7 @@ SET(FemScripts_SRCS
     FemToolsCcx.py
     ObjectsFem.py
     FemUtils.py
+    FemConstraint.py
     TestFem.py
 )
 #SOURCE_GROUP("Scripts" FILES ${FemScripts_SRCS})

src/Mod/Fem/CMakeLists.txt

@@ -40,6 +40,7 @@ INSTALL(
         FemToolsCcx.py
         ObjectsFem.py
         FemUtils.py
+        FemConstraint.py
         TestFem.py
     DESTINATION
         Mod/Fem

src/Mod/Fem/FemConstraint.py

@@ -0,0 +1,61 @@
+# ***************************************************************************
+# *                                                                         *
+# *   Copyright (c) 2017 - Markus Hovorka <m.hovorka@live.de>               *
+# *                                                                         *
+# *   This program is free software; you can redistribute it and/or modify  *
+# *   it under the terms of the GNU Lesser General Public License (LGPL)    *
+# *   as published by the Free Software Foundation; either version 2 of     *
+# *   the License, or (at your option) any later version.                   *
+# *   for detail see the LICENCE text file.                                 *
+# *                                                                         *
+# *   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 Library General Public License for more details.                  *
+# *                                                                         *
+# *   You should have received a copy of the GNU Library General Public     *
+# *   License along with this program; if not, write to the Free Software   *
+# *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  *
+# *   USA                                                                   *
+# *                                                                         *
+# ***************************************************************************
+
+
+__title__ = "_Base"
+__author__ = "Markus Hovorka"
+__url__ = "http://www.freecadweb.org"
+
+
+import FreeCAD
+if FreeCAD.GuiUp:
+    from pivy import coin
+
+
+class Proxy(object):
+
+    BaseType = "Fem::ConstraintPython"
+
+    def __init__(self, obj):
+        obj.Proxy = self
+
+
+class ViewProxy(object):
+    """Proxy for FemSolverElmers View Provider."""
+
+    def __init__(self, vobj):
+        vobj.Proxy = self
+
+    def attach(self, vobj):
+        default = coin.SoGroup()
+        vobj.addDisplayMode(default, "Default")
+
+    def getDisplayModes(self, obj):
+        "Return a list of display modes."
+        modes = ["Default"]
+        return modes
+
+    def getDefaultDisplayMode(self):
+        return "Default"
+
+    def setDisplayMode(self, mode):
+        return mode