PartDesign: Fix bug of mirror transformation of multiple features

fixes #3317

This code ensures that an individual transformation or a multi-transformation have a proper
base feature and next feature.

src/Mod/PartDesign/App/Body.cpp

@@ -206,8 +206,17 @@ bool Body::isMemberOfMultiTransform(const App::DocumentObject* f)
     if (f == NULL)
         return false;
 
+    // ORIGINAL COMMENT:
     // This can be recognized because the Originals property is empty (it is contained
     // in the MultiTransform instead)
+    // COMMENT ON THE COMMENT:
+    // This is wrong because at the creation (addObject) and before assigning the originals, that 
+    // is when this code is executed, the originals property is indeed empty.
+    //
+    // However, for the purpose of setting the base feature, the transform feature has been modified
+    // to auto set it when the originals are not null. See:
+    // App::DocumentObjectExecReturn *Transformed::execute(void)
+    //
     return (f->getTypeId().isDerivedFrom(PartDesign::Transformed::getClassTypeId()) &&
             static_cast<const PartDesign::Transformed*>(f)->Originals.getValues().empty());
 }
@@ -320,12 +329,18 @@ void Body::insertObject(App::DocumentObject* feature, App::DocumentObject* targe
     Group.setValues (model);
 
     // Set the BaseFeature property
+    setBaseProperty(feature);
+
+}
+
+void Body::setBaseProperty(App::DocumentObject* feature)
+{
     if (Body::isSolidFeature(feature)) {
         // Set BaseFeature property to previous feature (this might be the Tip feature)
         App::DocumentObject* prevSolidFeature = getPrevSolidFeature(feature);
         // NULL is ok here, it just means we made the current one fiature the base solid
         static_cast<PartDesign::Feature*>(feature)->BaseFeature.setValue(prevSolidFeature);
-
+        
         // Reroute the next solid feature's BaseFeature property to this feature
         App::DocumentObject* nextSolidFeature = getNextSolidFeature(feature);
         if (nextSolidFeature) {
@@ -333,10 +348,8 @@ void Body::insertObject(App::DocumentObject* feature, App::DocumentObject* targe
             static_cast<PartDesign::Feature*>(nextSolidFeature)->BaseFeature.setValue(feature);
         }
     }
-
 }
 
-
 std::vector<App::DocumentObject*> Body::removeObject(App::DocumentObject* feature)
 {
     App::DocumentObject* nextSolidFeature = getNextSolidFeature(feature);

src/Mod/PartDesign/App/Body.h

@@ -84,6 +84,8 @@ public:
      */
     void insertObject(App::DocumentObject* feature, App::DocumentObject* target, bool after=false);
 
+    void setBaseProperty(App::DocumentObject* feature);
+    
     /// Remove the feature from the body
     virtual std::vector<DocumentObject*> removeObject(DocumentObject* obj) override;
 

src/Mod/PartDesign/App/FeatureTransformed.cpp

@@ -44,6 +44,7 @@
 #include "FeatureLinearPattern.h"
 #include "FeaturePolarPattern.h"
 #include "FeatureSketchBased.h"
+#include "Body.h"
 
 #include <Base/Console.h>
 #include <Base/Exception.h>
@@ -200,8 +201,18 @@ App::DocumentObjectExecReturn *Transformed::execute(void)
     rejected.clear();
 
     std::vector<App::DocumentObject*> originals = Originals.getValues();
-    if (originals.empty()) // typically InsideMultiTransform
+    if (originals.empty()) {// typically InsideMultiTransform
         return App::DocumentObject::StdReturn;
+    }
+    else {
+        if(!this->BaseFeature.getValue()) {
+            auto body = getFeatureBody();
+
+            if(body) {
+                body->setBaseProperty(this);
+            }
+        }
+    }
 
     this->positionBySupport();