Core: Add getPlacementOf replacing previous getGlobalPlacement logic. (#26059)

* Core: Add getPlacementOf replacing previous getGlobalPlacement logic.

* Update src/App/DocumentObject.cpp

Co-authored-by: Kacper Donat <kadet1090@gmail.com>

* Update DocumentObject.cpp

* Fix error when called from python with targetObj == None

---------

Co-authored-by: Kacper Donat <kadet1090@gmail.com>

src/Mod/Assembly/UtilsAssembly.py

@@ -383,7 +383,7 @@ def getGlobalPlacement(ref, targetObj=None):
     rootObj = ref[0]
     subName = ref[1][0]
 
-    return App.GeoFeature.getGlobalPlacementOf(targetObj, rootObj, subName)
+    return rootObj.getPlacementOf(subName, targetObj)
 
 
 def isThereOneRootAssembly():

src/Mod/Draft/draftobjects/draftlink.py

@@ -253,6 +253,54 @@ class DraftLink(DraftObject):
                 else:
                     obj.setPropertyStatus("PlacementList", "Immutable")
 
+    def getPlacementOf(self, fp, subname, targetObj=None):
+        """
+        Return the placement of the sub-object relative to the link object.
+        """
+
+        # _getShowElementValue is mapped to ExpandArray.
+        if getattr(fp, "ExpandArray", False):
+            # Return None to fall back to the C++ implementation
+            return None
+
+        # We start with the object's own placement.
+        plc = fp.Placement
+
+        if not subname:
+            return plc
+
+        names = subname.split(".")
+
+        linked_obj = getattr(fp, "Base", None)
+        if not names or fp == targetObj or not linked_obj:
+            return plc
+
+        doc = linked_obj.Document
+
+        try:
+            i = int(names[0])
+        except ValueError:
+            return None
+
+        # Check bounds in PlacementList
+        plcs = fp.PlacementList
+        if i < 0 or i >= len(plcs):
+            return plc
+
+        # Accumulate the element placement
+        plc = plc * plcs[i]
+
+        if len(names) < 2:
+            return plc
+
+        subObj = doc.getObject(names[1])
+        if not subObj:
+            return plc
+
+        newSub = ".".join(names[2:])
+
+        return plc * subObj.getPlacementOf(newSub, targetObj)
+
 
 # Alias for compatibility with old versions of v0.19
 _DraftLink = DraftLink