From 81bf735c62faafde506ba94930f7e573573762c8 Mon Sep 17 00:00:00 2001
From: azv <azv@opencascade.com>
Date: Fri, 15 Aug 2014 17:37:42 +0400
Subject: [PATCH] Issue #100: Unpredictable result of distance creation Added
 verification of a sign of a point-line distance constraint

---
 .../SketchSolver_ConstraintGroup.cpp          | 48 +++++++++++++++++++
 .../SketchSolver_ConstraintGroup.h            |  6 +++
 2 files changed, 54 insertions(+)

diff --git a/src/SketchSolver/SketchSolver_ConstraintGroup.cpp b/src/SketchSolver/SketchSolver_ConstraintGroup.cpp
index 2640da058..0e5878091 100644
--- a/src/SketchSolver/SketchSolver_ConstraintGroup.cpp
+++ b/src/SketchSolver/SketchSolver_ConstraintGroup.cpp
@@ -8,6 +8,7 @@
 
 #include <Events_Error.h>
 #include <Events_Loop.h>
+#include <GeomAPI_XY.h>
 #include <GeomDataAPI_Dir.h>
 #include <GeomDataAPI_Point.h>
 #include <GeomDataAPI_Point2D.h>
@@ -148,6 +149,14 @@ bool SketchSolver_ConstraintGroup::isInteract(
       FeaturePtr aFeature = aDoc->feature(aRC);
       if (myEntityFeatMap.find(aFeature) != myEntityFeatMap.end())
         return true;
+      // search attributes of a feature to be parameters of constraint
+      std::list< boost::shared_ptr<ModelAPI_Attribute> >
+        aFeatAttrList = aFeature->data()->attributes(std::string());
+      std::list< boost::shared_ptr<ModelAPI_Attribute> >::const_iterator
+        aFAIter = aFeatAttrList.begin();
+      for ( ; aFAIter != aFeatAttrList.end(); aFAIter++)
+        if (myEntityAttrMap.find(*aFAIter) != myEntityAttrMap.end())
+          return true;
     }
   }
 
@@ -155,6 +164,41 @@ bool SketchSolver_ConstraintGroup::isInteract(
   return false;
 }
 
+// ============================================================================
+//  Function: checkConstraintConsistence
+//  Class:    SketchSolver_ConstraintGroup
+//  Purpose:  verifies and changes parameters of the constraint
+// ============================================================================
+void SketchSolver_ConstraintGroup::checkConstraintConsistence(Slvs_Constraint& theConstraint)
+{
+  if (theConstraint.type == SLVS_C_PT_LINE_DISTANCE)
+  {
+    // Get constraint parameters and check the sign of constraint value
+    
+    // point coordinates
+    int aPtPos = Search(theConstraint.ptA, myEntities);
+    int aPtParamPos = Search(myEntities[aPtPos].param[0], myParams);
+    boost::shared_ptr<GeomAPI_XY> aPoint(
+      new GeomAPI_XY(myParams[aPtParamPos].val, myParams[aPtParamPos+1].val));
+
+    // line coordinates
+    int aLnPos = Search(theConstraint.entityA, myEntities);
+    aPtPos = Search(myEntities[aLnPos].point[0], myEntities);
+    aPtParamPos = Search(myEntities[aPtPos].param[0], myParams);
+    boost::shared_ptr<GeomAPI_XY> aStart(
+      new GeomAPI_XY(-myParams[aPtParamPos].val, -myParams[aPtParamPos+1].val));
+    aPtPos = Search(myEntities[aLnPos].point[1], myEntities);
+    aPtParamPos = Search(myEntities[aPtPos].param[0], myParams);
+    boost::shared_ptr<GeomAPI_XY> aEnd(
+      new GeomAPI_XY(myParams[aPtParamPos].val, myParams[aPtParamPos+1].val));
+
+    aEnd = aEnd->added(aStart);
+    aPoint = aPoint->added(aStart);
+    if (aPoint->cross(aEnd) * theConstraint.valA < 0.0)
+      theConstraint.valA *= -1.0;
+  }
+}
+
 // ============================================================================
 //  Function: changeConstraint
 //  Class:    SketchSolver_ConstraintGroup
@@ -260,7 +304,11 @@ bool SketchSolver_ConstraintGroup::changeConstraint(
                           aDistance, aConstrEnt[0], aConstrEnt[1], aConstrEnt[2], aConstrEnt[3]);
     myConstraints.push_back(aConstraint);
     myConstraintMap[theConstraint] = aConstraint.h;
+    int aConstrPos = Search(aConstraint.h, myConstraints);
+    aConstrIter = myConstraints.begin() + aConstrPos;
   }
+
+  checkConstraintConsistence(*aConstrIter);
   return true;
 }
 
diff --git a/src/SketchSolver/SketchSolver_ConstraintGroup.h b/src/SketchSolver/SketchSolver_ConstraintGroup.h
index a648fc9b3..1ec223627 100644
--- a/src/SketchSolver/SketchSolver_ConstraintGroup.h
+++ b/src/SketchSolver/SketchSolver_ConstraintGroup.h
@@ -174,6 +174,12 @@ private:
    */
   bool addCoincidentPoints(const Slvs_hEntity& thePoint1, const Slvs_hEntity& thePoint2);
 
+  /** \brief Verifies and changes parameters of constriant, 
+   *         e.g. sign of the distance between line and point
+   *  \param[in,out] theConstraint SolveSpace constraint to be verified
+   */
+  void checkConstraintConsistence(Slvs_Constraint& theConstraint);
+
 private:
   // SolveSpace entities
   Slvs_hGroup                  myID;            ///< the index of the group
-- 
2.39.2