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Fix wrong unprompted update of entities on non-active sketches
[modules/shaper.git] / src / SketchSolver / SketchSolver_Manager.cpp
index 34b2ea0405d432afa86608c2ee8a5c0fbf683b0e..5867d6b94ed72ee786f611536ad14829f3363c8a 100644 (file)
@@ -5,8 +5,12 @@
 // Author:  Artem ZHIDKOV
 
 #include "SketchSolver_Manager.h"
+#include "SketchSolver_Error.h"
 
 #include <Events_Loop.h>
+
+#include <GeomDataAPI_Point2D.h>
+
 #include <ModelAPI_AttributeDouble.h>
 #include <ModelAPI_AttributeRefList.h>
 #include <ModelAPI_Data.h>
 #include <ModelAPI_Object.h>
 #include <ModelAPI_ResultConstruction.h>
 #include <ModelAPI_Attribute.h>
+#include <ModelAPI_AttributeInteger.h>
+#include <ModelAPI_AttributeString.h>
 
 #include <SketchPlugin_Constraint.h>
+#include <SketchPlugin_ConstraintAngle.h>
+#include <SketchPlugin_ConstraintCoincidence.h>
+#include <SketchPlugin_ConstraintCollinear.h>
+#include <SketchPlugin_ConstraintDistance.h>
+#include <SketchPlugin_ConstraintEqual.h>
+#include <SketchPlugin_ConstraintHorizontal.h>
+#include <SketchPlugin_ConstraintLength.h>
+#include <SketchPlugin_ConstraintMiddle.h>
+#include <SketchPlugin_ConstraintMirror.h>
+#include <SketchPlugin_ConstraintParallel.h>
+#include <SketchPlugin_ConstraintPerpendicular.h>
+#include <SketchPlugin_ConstraintRadius.h>
+#include <SketchPlugin_ConstraintRigid.h>
+#include <SketchPlugin_ConstraintTangent.h>
+#include <SketchPlugin_ConstraintVertical.h>
+#include <SketchPlugin_MultiRotation.h>
+#include <SketchPlugin_MultiTranslation.h>
 
 #include <SketchPlugin_Arc.h>
 #include <SketchPlugin_Circle.h>
 #include <SketchPlugin_Sketch.h>
 #include <SketchPlugin_Feature.h>
 
+#include <assert.h>
 #include <list>
 #include <set>
 #include <memory>
+#include <sstream>
+
+static const Events_ID anUpdateEvent = Events_Loop::eventByName(EVENT_OBJECT_UPDATED);
 
 // Initialization of constraint manager self pointer
 SketchSolver_Manager* SketchSolver_Manager::mySelf = 0;
@@ -55,6 +82,9 @@ SketchSolver_Manager::SketchSolver_Manager()
   Events_Loop::loop()->registerListener(this, Events_Loop::eventByName(EVENT_OBJECT_UPDATED));
   Events_Loop::loop()->registerListener(this, Events_Loop::eventByName(EVENT_OBJECT_DELETED));
   Events_Loop::loop()->registerListener(this, Events_Loop::eventByName(EVENT_OBJECT_MOVED));
+
+  Events_Loop::loop()->registerListener(this, Events_Loop::eventByName(EVENT_SOLVER_FAILED));
+  Events_Loop::loop()->registerListener(this, Events_Loop::eventByName(EVENT_SOLVER_REPAIRED));
 }
 
 SketchSolver_Manager::~SketchSolver_Manager()
@@ -79,9 +109,14 @@ BuilderPtr SketchSolver_Manager::builder()
 void SketchSolver_Manager::processEvent(
   const std::shared_ptr<Events_Message>& theMessage)
 {
+  checkConflictingConstraints(theMessage);
   if (myIsComputed)
     return;
   myIsComputed = true;
+
+  // Shows that the message has at least one feature applicable for solver
+  bool hasProperFeature = false;
+
   if (theMessage->eventID() == Events_Loop::loop()->eventByName(EVENT_OBJECT_CREATED)
       || theMessage->eventID() == Events_Loop::loop()->eventByName(EVENT_OBJECT_UPDATED)
       || theMessage->eventID() == Events_Loop::loop()->eventByName(EVENT_OBJECT_MOVED)) {
@@ -89,8 +124,7 @@ void SketchSolver_Manager::processEvent(
         std::dynamic_pointer_cast<ModelAPI_ObjectUpdatedMessage>(theMessage);
     std::set<ObjectPtr> aFeatures = anUpdateMsg->objects();
 
-    // Shows the message has at least one feature applicable for solver
-    bool hasProperFeature = false;
+    bool isUpdateFlushed = stopSendUpdate();
 
     bool isMovedEvt = theMessage->eventID()
           == Events_Loop::loop()->eventByName(EVENT_OBJECT_MOVED);
@@ -99,11 +133,16 @@ void SketchSolver_Manager::processEvent(
       for (aFeatIter = aFeatures.begin(); aFeatIter != aFeatures.end(); aFeatIter++) {
         std::shared_ptr<SketchPlugin_Feature> aSFeature = 
             std::dynamic_pointer_cast<SketchPlugin_Feature>(*aFeatIter);
-        if (aSFeature) {
-          moveEntity(aSFeature);
+        if (aSFeature && moveEntity(aSFeature)) {
+          // Want to avoid recalculation of DoF too frequently.
+          // So, set the flag when the feature is really moved.
           hasProperFeature = true;
         }
       }
+      if (!hasProperFeature) // in this iteration it will compute nothing, so, no problem with recursion
+        // it is important that solver flushes signal updated after processing move signal as there is
+        // optimization that relies on this update, might be found by key "optimization"
+        myIsComputed = false;
     } else {
       std::list<FeaturePtr> aSketchFeatures = SketchSolver_Group::selectApplicableFeatures(aFeatures);
       std::list<FeaturePtr>::iterator aFeatIter = aSketchFeatures.begin();
@@ -122,9 +161,18 @@ void SketchSolver_Manager::processEvent(
       }
     }
 
+    bool needToUpdate = false;
     // Solve the set of constraints
     if (hasProperFeature)
-      resolveConstraints(isMovedEvt); // send update for movement in any case
+      needToUpdate = resolveConstraints();
+
+    // Features may be updated => now send events, but for all changed at once
+    if (isUpdateFlushed)
+      allowSendUpdate();
+    // send update for movement in any case
+    if (needToUpdate || isMovedEvt)
+      Events_Loop::loop()->flush(anUpdateEvent);
+
   } else if (theMessage->eventID() == Events_Loop::loop()->eventByName(EVENT_OBJECT_DELETED)) {
     std::shared_ptr<ModelAPI_ObjectDeletedMessage> aDeleteMsg =
       std::dynamic_pointer_cast<ModelAPI_ObjectDeletedMessage>(theMessage);
@@ -138,28 +186,77 @@ void SketchSolver_Manager::processEvent(
         break;
 
     if (aFGrIter != aFeatureGroups.end()) {
-      std::vector<SketchSolver_Group*>::iterator aGroupIter = myGroups.begin();
+      hasProperFeature = true;
+      std::list<SketchSolver_Group*> aGroupsToResolve;
+      std::list<SketchSolver_Group*>::iterator aGroupIter = myGroups.begin();
       std::list<SketchSolver_Group*> aSeparatedGroups;
       while (aGroupIter != myGroups.end()) {
         if (!(*aGroupIter)->isWorkplaneValid()) {  // the group should be removed
           delete *aGroupIter;
-          int aShift = aGroupIter - myGroups.begin();
-          myGroups.erase(aGroupIter);
-          aGroupIter = myGroups.begin() + aShift;
+          std::list<SketchSolver_Group*>::iterator aRemoveIt = aGroupIter++;
+          myGroups.erase(aRemoveIt);
           continue;
         }
         if (!(*aGroupIter)->isConsistent()) {  // some constraints were removed, try to split the group
           (*aGroupIter)->splitGroup(aSeparatedGroups);
+          if (!(*aGroupIter)->getWorkplane()->string(
+              SketchPlugin_Sketch::SOLVER_ERROR())->value().empty() ||
+              (*aGroupIter)->isFailed())
+            aGroupsToResolve.push_back(*aGroupIter);
         }
         aGroupIter++;
       }
-      if (aSeparatedGroups.size() > 0)
+      if (aSeparatedGroups.size() > 0) {
         myGroups.insert(myGroups.end(), aSeparatedGroups.begin(), aSeparatedGroups.end());
+        aGroupsToResolve.insert(aGroupsToResolve.end(),
+            aSeparatedGroups.begin(), aSeparatedGroups.end());
+      }
+
+      if (!aGroupsToResolve.empty())
+        resolveConstraints(aGroupsToResolve);
     }
   }
+
+  if (hasProperFeature)
+    degreesOfFreedom();
   myIsComputed = false;
 }
 
+void SketchSolver_Manager::checkConflictingConstraints(const std::shared_ptr<Events_Message>& theMessage)
+{
+  if (theMessage->eventID() == Events_Loop::loop()->eventByName(EVENT_SOLVER_REPAIRED)) {
+    std::shared_ptr<ModelAPI_SolverFailedMessage> aMessage =
+        std::dynamic_pointer_cast<ModelAPI_SolverFailedMessage>(theMessage);
+    std::set<ObjectPtr> aSentObjs = aMessage->objects();
+    if (!aSentObjs.empty()) {
+      // Obtain sketch where the constraints are placed.
+      // It is enough to check only one constraint.
+      CompositeFeaturePtr aSketch;
+      FeaturePtr aConstraint = ModelAPI_Feature::feature(*aSentObjs.begin());
+      std::list<SketchSolver_Group*>::const_iterator aGrIt = myGroups.begin();
+      for (; aGrIt != myGroups.end(); ++aGrIt)
+        if ((*aGrIt)->isInteract(aConstraint)) {
+          aSketch = (*aGrIt)->getWorkplane();
+          break;
+        }
+
+      // Search failed groups built on the same sketch
+      if (aSketch) {
+        for (aGrIt = myGroups.begin(); aGrIt != myGroups.end(); ++aGrIt) {
+          SketchSolver_Group* aGroup = *aGrIt;
+          if (aGroup->isBaseWorkplane(aSketch) && aGroup->isFailed() &&
+              !aGroup->isInteract(aConstraint)) {
+            // reset error message on the sketch
+            aGroup->getWorkplane()->string(SketchPlugin_Sketch::SOLVER_ERROR())->setValue(
+                SketchSolver_Error::CONSTRAINTS());
+            break;
+          }
+        }
+      }
+    }
+  }
+}
+
 // ============================================================================
 //  Function: changeWorkplane
 //  Purpose:  update workplane by given parameters of the sketch
@@ -169,7 +266,7 @@ bool SketchSolver_Manager::changeWorkplane(CompositeFeaturePtr theSketch)
   bool aResult = true;  // changed when a workplane wrongly updated
   bool isUpdated = false;
   // Try to update specified workplane in all groups
-  std::vector<SketchSolver_Group*>::iterator aGroupIter;
+  std::list<SketchSolver_Group*>::iterator aGroupIter;
   for (aGroupIter = myGroups.begin(); aGroupIter != myGroups.end(); aGroupIter++)
     if ((*aGroupIter)->isBaseWorkplane(theSketch)) {
       isUpdated = true;
@@ -185,7 +282,7 @@ bool SketchSolver_Manager::changeWorkplane(CompositeFeaturePtr theSketch)
     }
     myGroups.push_back(aNewGroup);
   }
-  return aResult;
+  return aResult || isUpdated;
 }
 
 // ============================================================================
@@ -218,7 +315,7 @@ bool SketchSolver_Manager::changeFeature(std::shared_ptr<SketchPlugin_Feature> t
     return true;
   } else if (aGroups.size() == 1) {  // Only one group => add feature into it
     GroupID aGroupId = *(aGroups.begin());
-    std::vector<SketchSolver_Group*>::iterator aGroupIter;
+    std::list<SketchSolver_Group*>::iterator aGroupIter;
     for (aGroupIter = myGroups.begin(); aGroupIter != myGroups.end(); aGroupIter++)
       if ((*aGroupIter)->getId() == aGroupId) {
         // If the group is empty, the feature is not added (the constraint only)
@@ -230,7 +327,7 @@ bool SketchSolver_Manager::changeFeature(std::shared_ptr<SketchPlugin_Feature> t
     std::set<GroupID>::const_iterator aGroupsIter = aGroups.begin();
 
     // Search first group
-    std::vector<SketchSolver_Group*>::iterator aFirstGroupIter;
+    std::list<SketchSolver_Group*>::iterator aFirstGroupIter;
     for (aFirstGroupIter = myGroups.begin(); aFirstGroupIter != myGroups.end(); aFirstGroupIter++)
       if ((*aFirstGroupIter)->getId() == *aGroupsIter)
         break;
@@ -238,28 +335,30 @@ bool SketchSolver_Manager::changeFeature(std::shared_ptr<SketchPlugin_Feature> t
       return false;
 
     // Append other groups to the first one
-    std::vector<SketchSolver_Group*>::iterator anOtherGroupIter = aFirstGroupIter + 1;
+    std::list<SketchSolver_Group*>::iterator anOtherGroupIter = aFirstGroupIter;
+    ++anOtherGroupIter;
     for (aGroupsIter++; aGroupsIter != aGroups.end(); aGroupsIter++) {
       for (; anOtherGroupIter != myGroups.end(); anOtherGroupIter++)
         if ((*anOtherGroupIter)->getId() == *aGroupsIter)
           break;
       if (anOtherGroupIter == myGroups.end()) {  // Group disappears
-        anOtherGroupIter = aFirstGroupIter + 1;
+        anOtherGroupIter = aFirstGroupIter;
+        ++anOtherGroupIter;
         continue;
       }
 
       (*aFirstGroupIter)->mergeGroups(**anOtherGroupIter);
-      int aShiftFirst = aFirstGroupIter - myGroups.begin();
-      int aShiftOther = anOtherGroupIter - myGroups.begin();
-      delete *anOtherGroupIter;
-      myGroups.erase(anOtherGroupIter);
-      aFirstGroupIter = myGroups.begin() + aShiftFirst;
-      anOtherGroupIter = myGroups.begin() + aShiftOther;
+      std::list<SketchSolver_Group*>::iterator aRemoveIt = anOtherGroupIter++;
+      delete *aRemoveIt;
+      myGroups.erase(aRemoveIt);
     }
 
     if (aConstraint)
-      return (*aFirstGroupIter)->changeConstraint(aConstraint);
-    return (*aFirstGroupIter)->updateFeature(theFeature);
+      (*aFirstGroupIter)->changeConstraint(aConstraint);
+    else
+      (*aFirstGroupIter)->updateFeature(theFeature);
+    // groups are merged => need to resolve them
+    return true;
   }
 
   // Something goes wrong
@@ -270,12 +369,44 @@ bool SketchSolver_Manager::changeFeature(std::shared_ptr<SketchPlugin_Feature> t
 //  Function: moveEntity
 //  Purpose:  update element moved on the sketch, which is used by constraints
 // ============================================================================
-void SketchSolver_Manager::moveEntity(std::shared_ptr<SketchPlugin_Feature> theFeature)
+bool SketchSolver_Manager::moveEntity(std::shared_ptr<SketchPlugin_Feature> theFeature)
 {
-  std::vector<SketchSolver_Group*>::iterator aGroupIt = myGroups.begin();
+  bool isMoved = false;
+  std::list<SketchSolver_Group*>::iterator aGroupIt = myGroups.begin();
   for (; aGroupIt != myGroups.end(); aGroupIt++)
     if (!(*aGroupIt)->isEmpty() && (*aGroupIt)->isInteract(theFeature))
-      (*aGroupIt)->moveFeature(theFeature);
+      isMoved = (*aGroupIt)->moveFeature(theFeature) || isMoved;
+
+  if (!isMoved && theFeature->getKind() == SketchPlugin_Arc::ID()) {
+    // Workaround to move arc.
+    // If the arc has not been constrained, we will push it into empty group and apply movement.
+    bool hasEmptyGroup = false;
+    for (aGroupIt = myGroups.begin(); aGroupIt != myGroups.end(); aGroupIt++)
+      if ((*aGroupIt)->isEmpty()) {
+        isMoved = (*aGroupIt)->moveFeature(theFeature) || isMoved;
+        hasEmptyGroup = true;
+      }
+    // There is no empty group, create it explicitly
+    if (!hasEmptyGroup) {
+      // find sketch containing the arc
+      CompositeFeaturePtr aWP;
+      const std::set<AttributePtr>& aRefs = theFeature->data()->refsToMe();
+      std::set<AttributePtr>::const_iterator aRefIt = aRefs.begin();
+      for (; aRefIt != aRefs.end(); ++aRefIt) {
+        FeaturePtr anOwner = ModelAPI_Feature::feature((*aRefIt)->owner());
+        if (anOwner && anOwner->getKind() == SketchPlugin_Sketch::ID()) {
+          aWP = std::dynamic_pointer_cast<ModelAPI_CompositeFeature>(anOwner);
+          break;
+        }
+      }
+      if (aWP) {
+        SketchSolver_Group* aGroup = new SketchSolver_Group(aWP);
+        isMoved = aGroup->moveFeature(theFeature) || isMoved;
+        myGroups.push_back(aGroup);
+      }
+    }
+  }
+  return isMoved;
 }
 
 // ============================================================================
@@ -289,7 +420,7 @@ void SketchSolver_Manager::findGroups(
   std::shared_ptr<ModelAPI_CompositeFeature> aWP = findWorkplane(theFeature);
 
   SketchSolver_Group* anEmptyGroup = 0;  // appropriate empty group for specified constraint
-  std::vector<SketchSolver_Group*>::const_iterator aGroupIter;
+  std::list<SketchSolver_Group*>::const_iterator aGroupIter;
   for (aGroupIter = myGroups.begin(); aGroupIter != myGroups.end(); aGroupIter++)
     if (aWP == (*aGroupIter)->getWorkplane() && (*aGroupIter)->isInteract(theFeature)) {
       if (!(*aGroupIter)->isEmpty())
@@ -313,7 +444,7 @@ std::shared_ptr<ModelAPI_CompositeFeature> SketchSolver_Manager
   // Already verified workplanes
   std::set<std::shared_ptr<ModelAPI_CompositeFeature> > aVerified;
 
-  std::vector<SketchSolver_Group*>::const_iterator aGroupIter;
+  std::list<SketchSolver_Group*>::const_iterator aGroupIter;
   for (aGroupIter = myGroups.begin(); aGroupIter != myGroups.end(); aGroupIter++) {
     std::shared_ptr<ModelAPI_CompositeFeature> aWP = (*aGroupIter)->getWorkplane();
     if (aVerified.find(aWP) != aVerified.end())
@@ -339,30 +470,369 @@ std::shared_ptr<ModelAPI_CompositeFeature> SketchSolver_Manager
 //  Function: resolveConstraints
 //  Purpose:  change entities according to available constraints
 // ============================================================================
-void SketchSolver_Manager::resolveConstraints(const bool theForceUpdate)
+bool SketchSolver_Manager::resolveConstraints(const std::list<SketchSolver_Group*>& theGroups)
 {
-  //myIsComputed = true;
   bool needToUpdate = false;
-  static Events_ID anUpdateEvent = Events_Loop::eventByName(EVENT_OBJECT_UPDATED);
+  const std::list<SketchSolver_Group*>& aGroupsToResolve = theGroups.empty() ? myGroups : theGroups;
+  std::list<SketchSolver_Group*>::const_iterator aGroupIter = aGroupsToResolve.begin();
+  for (; aGroupIter != aGroupsToResolve.end(); aGroupIter++)
+    if ((*aGroupIter)->resolveConstraints())
+      needToUpdate = true;
+  return needToUpdate;
+}
+
+
+// Obtain points and their copies for Mirror, Multi-Rotation and Multi-Translation constraints
+static void collectPointsAndCopies(FeaturePtr theConstraint, std::list<std::set<AttributePtr> >& thePoints)
+{
+  typedef std::list<std::string> strlist;
+  static strlist aPointAttributes(1, SketchPlugin_Point::COORD_ID());
+  static strlist aLineAttributes;
+  if (aLineAttributes.empty()) {
+    aLineAttributes.push_back(SketchPlugin_Line::START_ID());
+    aLineAttributes.push_back(SketchPlugin_Line::END_ID());
+  };
+  static strlist aCircleAttributes(1, SketchPlugin_Circle::CENTER_ID());
+  static strlist anArcAttributes;
+  if (anArcAttributes.empty()) {
+    anArcAttributes.push_back(SketchPlugin_Arc::CENTER_ID());
+    anArcAttributes.push_back(SketchPlugin_Arc::START_ID());
+    anArcAttributes.push_back(SketchPlugin_Arc::END_ID());
+  };
+
+  static std::map<std::string, strlist> aFeatureAttributes;
+  if (aFeatureAttributes.empty()) {
+    aFeatureAttributes[SketchPlugin_Point::ID()] = aPointAttributes;
+    aFeatureAttributes[SketchPlugin_Line::ID()] = aLineAttributes;
+    aFeatureAttributes[SketchPlugin_Circle::ID()] = aCircleAttributes;
+    aFeatureAttributes[SketchPlugin_Arc::ID()] = anArcAttributes;
+  }
+
+
+  std::set<AttributePtr> aPoints;
+  if (theConstraint->getKind() == SketchPlugin_ConstraintMirror::ID()) {
+    AttributeRefListPtr aBaseRefList = theConstraint->reflist(SketchPlugin_Constraint::ENTITY_B());
+    AttributeRefListPtr aMirrRefList = theConstraint->reflist(SketchPlugin_Constraint::ENTITY_C());
+
+    std::list<ObjectPtr> aBaseList = aBaseRefList->list();
+    std::list<ObjectPtr> aMirrList = aMirrRefList->list();
+    std::list<ObjectPtr>::const_iterator aBIt, aMIt;
+    for (aBIt = aBaseList.begin(), aMIt = aMirrList.begin();
+         aBIt != aBaseList.end() && aMIt != aMirrList.end(); ++aBIt, ++aMIt) {
+      FeaturePtr aBaseFeature = ModelAPI_Feature::feature(*aBIt);
+      FeaturePtr aMirrFeature = ModelAPI_Feature::feature(*aMIt);
+
+      strlist anAttrList = aFeatureAttributes[aBaseFeature->getKind()];
+      strlist::iterator anIt = anAttrList.begin();
+      for (; anIt != anAttrList.end(); ++anIt) {
+        aPoints.clear();
+        aPoints.insert(aBaseFeature->attribute(*anIt));
+        aPoints.insert(aMirrFeature->attribute(*anIt));
+        thePoints.push_back(aPoints);
+      }
+    }
+  }
+  else { // the "Multi" constraints
+    std::string aNbObjName;
+    if (theConstraint->getKind() == SketchPlugin_MultiRotation::ID())
+      aNbObjName = SketchPlugin_MultiRotation::NUMBER_OF_OBJECTS_ID();
+    else
+      aNbObjName = SketchPlugin_MultiTranslation::NUMBER_OF_OBJECTS_ID();
+    int aNbCopies = theConstraint->integer(aNbObjName)->value();
+
+    AttributeRefListPtr aRefList = theConstraint->reflist(SketchPlugin_Constraint::ENTITY_B());
+    std::list<ObjectPtr> aFullList = aRefList->list();
+    std::list<ObjectPtr>::const_iterator anObjIt = aFullList.begin();
+    std::list<ObjectPtr>::const_iterator aCopyIt;
+    while (anObjIt != aFullList.end()) {
+      FeaturePtr aBaseFeature = ModelAPI_Feature::feature(*anObjIt);
+      strlist anAttrList = aFeatureAttributes[aBaseFeature->getKind()];
+      strlist::iterator anIt = anAttrList.begin();
+      for (; anIt != anAttrList.end(); ++anIt) {
+        aPoints.clear();
+        aCopyIt = anObjIt;
+        for (int i = 0; i < aNbCopies && aCopyIt != aFullList.end(); ++i, ++aCopyIt) {
+          FeaturePtr aFeature = ModelAPI_Feature::feature(*aCopyIt);
+          aPoints.insert(aFeature->attribute(*anIt));
+        }
+        thePoints.push_back(aPoints);
+      }
+      anObjIt = aCopyIt;
+    }
+  }
+}
+
+// ============================================================================
+//  Function: degreesOfFreedom
+//  Purpose:  calculate DoFs for each sketch
+// ============================================================================
+void SketchSolver_Manager::degreesOfFreedom()
+{
+  static std::map<std::string, int> aDoFDelta; // indicates how many DoF adds or decreases a feature
+  static bool isNeedInit = true;
+  if (isNeedInit) {
+    aDoFDelta[SketchPlugin_Point::ID()] = 2;
+    aDoFDelta[SketchPlugin_Line::ID()] = 4;
+    aDoFDelta[SketchPlugin_Circle::ID()] = 3;
+    aDoFDelta[SketchPlugin_Arc::ID()] = 5;
+
+    aDoFDelta[SketchPlugin_ConstraintAngle::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintCollinear::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintDistance::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintEqual::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintHorizontal::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintLength::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintParallel::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintPerpendicular::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintRadius::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintTangent::ID()] = -1;
+    aDoFDelta[SketchPlugin_ConstraintVertical::ID()] = -1;
+
+    isNeedInit = false;
+  }
+
+  std::map<CompositeFeaturePtr, int> aSketchDoF;
+
+  std::list<SketchSolver_Group*>::const_iterator aGroupIt = myGroups.begin();
+  for (; aGroupIt != myGroups.end(); ++aGroupIt) {
+    CompositeFeaturePtr aSketch = (*aGroupIt)->getWorkplane();
+    bool isSketchValid = aSketch->data() && aSketch->data()->isValid();
+
+    if (isSketchValid) {
+      std::shared_ptr<GeomDataAPI_Dir> aNormal =
+          std::dynamic_pointer_cast<GeomDataAPI_Dir>(aSketch->data()->attribute(SketchPlugin_Sketch::NORM_ID()));
+      isSketchValid = aNormal && aNormal->isInitialized();
+    }
+
+    if (!isSketchValid) {
+      myDoF.erase(aSketch);
+      continue;
+    }
+
+    // check conflicting constraints in the group
+    if ((*aGroupIt)->isFailed())
+      aSketchDoF[aSketch] = -1;
+    // check the sketch is already processed
+    if (aSketchDoF.find(aSketch) != aSketchDoF.end() || aSketchDoF[aSketch] < 0)
+      continue;
+
+    std::set<AttributePtr> aCoincidentPoints;
+    std::set<AttributePtr> aFixedPoints;
+    std::map<AttributePtr, std::set<FeaturePtr> > aPointOnLine;
+    std::list<std::set<AttributePtr> > aPointsInMultiConstraints;
+    int aDoF = 0;
+    int aNbSubs = aSketch->numberOfSubs();
+    for (int i = 0; i < aNbSubs; ++i) {
+      FeaturePtr aFeature = aSketch->subFeature(i);
+      // check DoF delta for invariant types
+      std::map<std::string, int>::const_iterator aFound = aDoFDelta.find(aFeature->getKind());
+      if (aFound != aDoFDelta.end()) {
+        aDoF += aFound->second;
+        continue;
+      }
+
+      // DoF delta in specific cases
+      if (aFeature->getKind() == SketchPlugin_ConstraintCoincidence::ID()) {
+        AttributePtr aCoincPoint[2] = {AttributePtr(), AttributePtr()};
+        FeaturePtr aCoincLine;
+        for (int j = 0; j < 2; ++j) {
+          AttributeRefAttrPtr aRefAttr = std::dynamic_pointer_cast<ModelAPI_AttributeRefAttr>(
+              aFeature->attribute(SketchPlugin_Constraint::ATTRIBUTE(j)));
+          if (!aRefAttr)
+            continue;
+          if (!aRefAttr->isObject())
+            aCoincPoint[j] = aRefAttr->attr();
+          else {
+            FeaturePtr anAttr = ModelAPI_Feature::feature(aRefAttr->object());
+            if (!anAttr)
+              continue;
+            if (anAttr->getKind() == SketchPlugin_Point::ID())
+              aCoincPoint[j] = anAttr->attribute(SketchPlugin_Point::COORD_ID());
+            else if (anAttr->getKind() == SketchPlugin_Line::ID())
+              aCoincLine = anAttr;
+          }
+        }
+        if (aCoincPoint[0] && aCoincPoint[1]) {
+          bool isDoFDecreased = false;
+          // point-point coincidence
+          if (aCoincidentPoints.find(aCoincPoint[0]) == aCoincidentPoints.end() ||
+              aCoincidentPoints.find(aCoincPoint[1]) == aCoincidentPoints.end()) {
+            aDoF -= 2;
+            isDoFDecreased = true;
+          }
+          // check the coincident point is used in "multi" constraints
+          std::list<std::set<AttributePtr> >::const_iterator
+              aPtIt = aPointsInMultiConstraints.begin();
+          bool isFound[2] = {false, false};
+          for (; aPtIt != aPointsInMultiConstraints.end(); ++aPtIt) {
+            if ((!isFound[0] && (isFound[0] = (aPtIt->find(aCoincPoint[0]) != aPtIt->end())))
+             || (!isFound[1] && (isFound[1] = (aPtIt->find(aCoincPoint[1]) != aPtIt->end()))))
+              aCoincidentPoints.insert(aPtIt->begin(), aPtIt->end());
+            if (isFound[0] && isFound[1])
+              break;
+          }
+          // check both points are fixed => not need to decrease DoF
+          bool isFixed[2] = { aFixedPoints.find(aCoincPoint[0]) != aFixedPoints.end(),
+                              aFixedPoints.find(aCoincPoint[1]) != aFixedPoints.end() };
+          if (isFixed[0] && isFixed[1] && isDoFDecreased)
+            aDoF += 2; // revert decrease of DoF
+          else if (isFixed[0] && !isFixed[1])
+            aFixedPoints.insert(aCoincPoint[1]);
+          else if (!isFixed[0] && isFixed[1])
+            aFixedPoints.insert(aCoincPoint[0]);
+        } else {
+          aDoF -= 1;
+          if (aCoincPoint[0] && aCoincLine) {
+            // if the point is already coincident to a line (by middle point constraint), do not decrease DoF
+            std::map<AttributePtr, std::set<FeaturePtr> >::iterator
+                aPtFound = aPointOnLine.find(aCoincPoint[0]);
+            if (aPtFound != aPointOnLine.end() &&
+                aPtFound->second.find(aCoincLine) != aPtFound->second.end())
+              aDoF += 1; // restore value decreased above
+            else
+              aPointOnLine[aCoincPoint[0]].insert(aCoincLine);
+          }
+        }
+        for (int j = 0; j < 2; ++j)
+          if (aCoincPoint[j])
+            aCoincidentPoints.insert(aCoincPoint[j]);
+      }
+      else if (aFeature->getKind() == SketchPlugin_ConstraintMiddle::ID()) {
+        AttributePtr aPoint;
+        FeaturePtr aLine;
+        for (int j = 0; j < 2; ++j) {
+          AttributeRefAttrPtr aRefAttr = std::dynamic_pointer_cast<ModelAPI_AttributeRefAttr>(
+              aFeature->attribute(SketchPlugin_Constraint::ATTRIBUTE(j)));
+          if (!aRefAttr)
+            continue;
+          if (aRefAttr->isObject())
+            aLine = ModelAPI_Feature::feature(aRefAttr->object());
+          else
+            aPoint = aRefAttr->attr();
+        }
+        if (aPoint && aLine) {
+          // if the point is already on the line, decrease 1 DoF, instead decrease 2 DoF
+          std::map<AttributePtr, std::set<FeaturePtr> >::iterator
+              aPtFound = aPointOnLine.find(aPoint);
+          if (aPtFound != aPointOnLine.end() &&
+              aPtFound->second.find(aLine) != aPtFound->second.end())
+            aDoF -= 1;
+          else {
+            aDoF -= 2;
+            aPointOnLine[aPoint].insert(aLine);
+          }
+        }
+      }
+      else if (aFeature->getKind() == SketchPlugin_ConstraintRigid::ID()) {
+        AttributeRefAttrPtr aRefAttr = std::dynamic_pointer_cast<ModelAPI_AttributeRefAttr>(
+            aFeature->attribute(SketchPlugin_Constraint::ENTITY_A()));
+        assert(aRefAttr);
+        std::set<AttributePtr> aPoints;
+        if (!aRefAttr->isObject()) {
+          aDoF -= 2; // attribute is a point
+          aPoints.insert(aRefAttr->attr());
+        } else {
+          FeaturePtr anAttr = ModelAPI_Feature::feature(aRefAttr->object());
+          if (anAttr)
+            aDoF -= aDoFDelta[anAttr->getKind()];
+          std::list<AttributePtr> aPtAttrs = anAttr->data()->attributes(GeomDataAPI_Point2D::typeId());
+          aPoints.insert(aPtAttrs.begin(), aPtAttrs.end());
+        }
+
+        // Check whether feature's points are already coincident with fixed points.
+        // In this case we need to revert decrease of DoF for these points.
+        // If the coordinates of fixed points are different, it will be processed by solver.
+        for (int k = 0; k < i; ++k) {
+          FeaturePtr aFeature = aSketch->subFeature(k);
+          if (aFeature->getKind() != SketchPlugin_ConstraintCoincidence::ID())
+            continue;
+          AttributePtr aCoincPoint[2] = {AttributePtr(), AttributePtr()};
+          for (int j = 0; j < 2; ++j) {
+            AttributeRefAttrPtr aRefAttr = std::dynamic_pointer_cast<ModelAPI_AttributeRefAttr>(
+                aFeature->attribute(SketchPlugin_Constraint::ATTRIBUTE(j)));
+            if (!aRefAttr)
+              continue;
+            if (!aRefAttr->isObject())
+              aCoincPoint[j] = aRefAttr->attr();
+            else {
+              FeaturePtr anAttr = ModelAPI_Feature::feature(aRefAttr->object());
+              if (anAttr && anAttr->getKind() == SketchPlugin_Point::ID())
+                aCoincPoint[j] = anAttr->attribute(SketchPlugin_Point::COORD_ID());
+            }
+          }
+          if (aCoincPoint[0] && aCoincPoint[1]) {
+            if ((aFixedPoints.find(aCoincPoint[0]) != aFixedPoints.end() &&
+                 aPoints.find(aCoincPoint[1]) != aPoints.end()) ||
+                (aFixedPoints.find(aCoincPoint[1]) != aFixedPoints.end() &&
+                 aPoints.find(aCoincPoint[0]) != aPoints.end()))
+              aDoF += 2; // point already fixed
+          }
+        }
+        // store fixed points
+        aFixedPoints.insert(aPoints.begin(), aPoints.end());
+      }
+      else if (aFeature->getKind() == SketchPlugin_ConstraintMirror::ID() ||
+               aFeature->getKind() == SketchPlugin_MultiRotation::ID() ||
+               aFeature->getKind() == SketchPlugin_MultiTranslation::ID()) {
+        int aNbCopies = 1;
+        std::string anAttrName;
+        if (aFeature->getKind() == SketchPlugin_ConstraintMirror::ID())
+          anAttrName = SketchPlugin_Constraint::ENTITY_B();
+        else {
+          if (aFeature->getKind() == SketchPlugin_MultiRotation::ID())
+            aNbCopies = aFeature->integer(SketchPlugin_MultiRotation::NUMBER_OF_OBJECTS_ID())->value() - 1;
+          else if (aFeature->getKind() == SketchPlugin_MultiTranslation::ID())
+            aNbCopies = aFeature->integer(SketchPlugin_MultiTranslation::NUMBER_OF_OBJECTS_ID())->value() - 1;
+          anAttrName = SketchPlugin_Constraint::ENTITY_A();
+        }
+
+        AttributeRefListPtr aRefListOfShapes = std::dynamic_pointer_cast<ModelAPI_AttributeRefList>(
+            aFeature->attribute(anAttrName));
+        std::list<ObjectPtr> anObjList = aRefListOfShapes->list();
+        std::list<ObjectPtr>::const_iterator anObjIt = anObjList.begin();
+        for (; anObjIt != anObjList.end(); ++anObjIt) {
+          FeaturePtr aSub = ModelAPI_Feature::feature(*anObjIt);
+          aDoF -= aDoFDelta[aSub->getKind()] * aNbCopies;
+        }
+        // collect points and their copies for correct calculation of DoF for coincident points
+        collectPointsAndCopies(aFeature, aPointsInMultiConstraints);
+      }
+    }
+
+    aSketchDoF[aSketch] = aDoF;
+  }
+
+  // Check the degrees of freedom are changed
+  std::map<CompositeFeaturePtr, int>::const_iterator aDoFIt = aSketchDoF.begin();
+  std::map<CompositeFeaturePtr, int>::iterator aFound;
+  for (; aDoFIt != aSketchDoF.end(); ++aDoFIt) {
+    if (aDoFIt->second < 0)
+      continue; // conflicting constraints on the current sketch
+    aFound = myDoF.find(aDoFIt->first);
+    if (aFound != myDoF.end() && aFound->second == aDoFIt->second)
+      continue; // nothing is changed
+    myDoF[aDoFIt->first] = aDoFIt->second;
+    // change attribute value
+    std::ostringstream aStream;
+    if (aDoFIt->second == 0)
+      aStream << "Sketch fully fixed (DOF = " << aDoFIt->second << ")";
+    else
+      aStream << "DOF (degree of freedom) = " << aDoFIt->second;
+    aDoFIt->first->data()->string(SketchPlugin_Sketch::SOLVER_DOF())->setValue(aStream.str());
+  }
+}
+
+bool SketchSolver_Manager::stopSendUpdate() const
+{
   // to avoid redisplay of each segment on update by solver one by one in the viewer
   bool isUpdateFlushed = Events_Loop::loop()->isFlushed(anUpdateEvent);
   if (isUpdateFlushed) {
     Events_Loop::loop()->setFlushed(anUpdateEvent, false);
   }
+  return isUpdateFlushed;
+}
 
-  std::vector<SketchSolver_Group*>::iterator aGroupIter;
-  for (aGroupIter = myGroups.begin(); aGroupIter != myGroups.end(); aGroupIter++)
-    if ((*aGroupIter)->resolveConstraints())
-      needToUpdate = true;
-
-  // Features may be updated => now send events, but for all changed at once
-  if (isUpdateFlushed) {
-    Events_Loop::loop()->setFlushed(anUpdateEvent, true);
-  }
-  // Must be before flush because on "Updated" flush the results may be produced
-  // and the creation event is appeared with many new objects. If myIsComputed these
-  // events are missed in processEvents and some elements are not added.
-  //myIsComputed = false;
-  if (needToUpdate || theForceUpdate)
-    Events_Loop::loop()->flush(anUpdateEvent);
+void SketchSolver_Manager::allowSendUpdate() const
+{
+  Events_Loop::loop()->setFlushed(anUpdateEvent, true);
 }