mover: support tracing any geometry element

assembly.py

@@ -1656,6 +1656,7 @@ class ViewProviderAssembly(ViewProviderAsmGroup):
     def initDraggingPlacement(self):
         if not getattr(self,'_movingPart',None):
             return
+        self._movingPart.begin()
         return (FreeCADGui.editDocument().EditingTransform,
                 self._movingPart.draggerPlacement,
                 self._movingPart.bbox)

gui.py

@@ -1,6 +1,6 @@
 from collections import OrderedDict
 import FreeCAD, FreeCADGui
-from .utils import objName,addIconToFCAD,guilogger as logger
+from .utils import getElementPos,objName,addIconToFCAD,guilogger as logger
 from .proxy import ProxyType
 from .FCADLogger import FCADLogger
 
@@ -267,6 +267,37 @@ class AsmCmdTrace(AsmCmdCheckable):
     _menuText = 'Trace part move'
     _iconName = 'Assembly_Trace.svg'
 
+    _object = None
+    _subname = None
+
+    @classmethod
+    def Activated(cls,checked):
+        super(AsmCmdTrace,cls).Activated(checked)
+        if not checked:
+            cls._object = None
+            return
+        sel = FreeCADGui.Selection.getSelectionEx('',False)
+        if len(sel)==1:
+            subs = sel[0].SubElementNames
+            if len(subs)==1:
+                cls._object = sel[0].Object
+                cls._subname = subs[0]
+                logger.info('trace {}.{}'.format(
+                    cls._object.Name,cls._subname))
+                return
+        logger.info('trace moving element')
+
+    @classmethod
+    def getPosition(cls):
+        if not cls._object:
+            return
+        try:
+            if cls._object.Document != FreeCAD.ActiveDocument:
+                cls._object = None
+            return getElementPos((cls._object,cls._subname))
+        except Exception:
+            cls._object = None
+
 class AsmCmdAutoRecompute(AsmCmdCheckable):
     _id = 5
     _menuText = 'Auto recompute'

mover.py

@@ -53,8 +53,8 @@ class AsmMovingPart(object):
         self.offset = pla.copy()
         self.offsetInv = pla.inverse()
         self.draggerPlacement = info.Placement.multiply(pla)
-        self.tracePoint = self.draggerPlacement.Base
         self.trace = None
+        self.tracePoint = None
 
     @classmethod
     def onRollback(cls):
@@ -66,7 +66,10 @@ class AsmMovingPart(object):
             movingPart = getattr(vobj.Proxy,'_movingPart',None)
             if movingPart:
                 vobj.Object.recompute(True)
-                movingPart.tracePoint = movingPart.draggerPlacement.Base
+                movingPart.tracePoint = movingPart.TracePosition
+
+    def begin(self):
+        self.tracePoint = self.TracePosition
 
     def update(self):
         info = getElementInfo(self.info.Parent,self.info.SubnameRef)
@@ -87,6 +90,14 @@ class AsmMovingPart(object):
                 self.draggerPlacement.inverse())
         return utils.roundPlacement(pla)
 
+    @property
+    def TracePosition(self):
+        pos = gui.AsmCmdTrace.getPosition()
+        if pos:
+            return pos
+        mat = FreeCADGui.editDocument().EditingTransform
+        return mat.multiply(self.draggerPlacement.Base)
+
     def move(self):
         info = self.info
         part = info.Part
@@ -95,7 +106,7 @@ class AsmMovingPart(object):
         updatePla = True
 
         rollback = []
-        if utils.isDraftWire(part):
+        if not info.Subname.startswith('Face') and utils.isDraftWire(part):
             updatePla = False
             if info.Subname.startswith('Vertex'):
                 idx = utils.draftWireVertex2PointIndex(part,info.Subname)
@@ -171,21 +182,21 @@ class AsmMovingPart(object):
                solver.solve, self.objs, dragPart=info.Part, rollback=rollback):
             obj.recompute(True)
 
-        if gui.AsmCmdManager.Trace and \
-           not self.tracePoint.isEqual(self.draggerPlacement.Base,1e-5):
-            try:
-                # check if the object is deleted
-                self.trace.Name
-            except Exception:
-                self.trace = None
-            mat = FreeCADGui.editDocument().EditingTransform
-            if not self.trace:
-                self.trace = FreeCAD.ActiveDocument.addObject(
-                    'Part::Polygon','AsmTrace')
-                self.trace.Nodes = {-1:mat.multiply(self.tracePoint)}
-            self.tracePoint = self.draggerPlacement.Base
-            self.trace.Nodes = {-1:mat.multiply(self.draggerPlacement.Base)}
-            self.trace.recompute()
+        if gui.AsmCmdManager.Trace:
+            pos = self.TracePosition
+            if not self.tracePoint.isEqual(pos,1e-5):
+                try:
+                    # check if the object is deleted
+                    self.trace.Name
+                except Exception:
+                    self.trace = None
+                if not self.trace:
+                    self.trace = FreeCAD.ActiveDocument.addObject(
+                        'Part::Polygon','AsmTrace')
+                    self.trace.Nodes = [self.tracePoint]
+                self.tracePoint = pos
+                self.trace.Nodes = {-1:pos}
+                self.trace.recompute()
 
         # self.draggerPlacement, which holds the intended dragger placement, is
         # updated by the above solver call through the following chain,