From cbc19a51971b014a3bddaa318215015b8e1ac926 Mon Sep 17 00:00:00 2001
From: Sebastian Hoogen <github@sebastianhoogen.de>
Date: Sun, 13 Apr 2014 12:44:58 +0200
Subject: [PATCH] Allow selection of two objects for OpenSCAD.replaceobject

---
 src/Mod/OpenSCAD/OpenSCADCommands.py | 11 +++++++---
 src/Mod/OpenSCAD/replaceobj.py       | 32 +++++++++++++++++++++-------
 2 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/Mod/OpenSCAD/OpenSCADCommands.py b/src/Mod/OpenSCAD/OpenSCADCommands.py
index 02d17be8f151..45b90ed7e38b 100644
--- a/src/Mod/OpenSCAD/OpenSCADCommands.py
+++ b/src/Mod/OpenSCAD/OpenSCADCommands.py
@@ -183,12 +183,17 @@ def GetResources(self):
 
 class ReplaceObject:
     def IsActive(self):
-        return FreeCADGui.Selection.countObjectsOfType('Part::Feature') == 3
+        nobj = FreeCADGui.Selection.countObjectsOfType('Part::Feature')
+        if nobj == 3: return True
+        elif nobj == 2: return tuple((len(obj.InList)) for obj in \
+                FreeCADGui.Selection.getSelection()) in ((0,1),(1,0))
+        #else: return False
+
     def Activated(self):
         import replaceobj
-        #objs=[selobj.Object for selobj in FreeCADGui.Selection.getSelectionEx()]
         objs=FreeCADGui.Selection.getSelection()
-        if len(objs)==3:
+        if len(objs)==3 or \
+                tuple((len(obj.InList)) for obj in objs) in ((0,1),(1,0)):
             replaceobj.replaceobjfromselection(objs)
         else:
             FreeCAD.Console.PrintError(unicode(translate('OpenSCAD',\
diff --git a/src/Mod/OpenSCAD/replaceobj.py b/src/Mod/OpenSCAD/replaceobj.py
index 384267b22183..290109303d4e 100644
--- a/src/Mod/OpenSCAD/replaceobj.py
+++ b/src/Mod/OpenSCAD/replaceobj.py
@@ -44,15 +44,31 @@ def replaceobj(parent,oldchild,newchild):
     parent.touch()
 
 def replaceobjfromselection(objs):
-    assert(len(objs)==3)
-    if objs[2] in objs[0].InList: oldchild, newchild, parent = objs
-    elif objs[0] in objs[1].InList: parent, oldchild, newchild = objs
-    elif objs[0] in objs[2].InList: parent, newchild, oldchild = objs
-    elif objs[1] in objs[0].InList: oldchild, parent, newchild = objs
-    elif objs[1] in objs[2].InList: newchild, parent, oldchild = objs
-    elif objs[2] in objs[1].InList: newchild, oldchild, parent = objs
-    else: assert(False)
+    # The Parent can be ommited as long as one object is orphaned
+    if len(objs)==2:
+        InListLength= tuple((len(obj.InList)) for obj in objs)
+        if InListLength == (0,1):
+            newchild,oldchild  = objs
+            parent = oldchild.InList[0]
+        elif InListLength == (1,0):
+            oldchild,newchild  = objs
+            parent = oldchild.InList[0]
+        else:
+            raise ValueError("Selection ambiguous. Please select oldchild,\
+            newchild and parent")
+    elif len(objs)==3:
+        if objs[2] in objs[0].InList: oldchild, newchild, parent = objs
+        elif objs[0] in objs[1].InList: parent, oldchild, newchild = objs
+        elif objs[0] in objs[2].InList: parent, newchild, oldchild = objs
+        elif objs[1] in objs[0].InList: oldchild, parent, newchild = objs
+        elif objs[1] in objs[2].InList: newchild, parent, oldchild = objs
+        elif objs[2] in objs[1].InList: newchild, oldchild, parent = objs
+        else:
+            raise ValueError("Cannot determin current parent-child relationship")
+    else:
+        raise ValueError("Wrong number of selected objects")
     replaceobj(parent,oldchild,newchild)
+    parent.Document.recompute()
 
 if __name__ == '__main__':
     import FreeCAD,FreeCADGui