Sketcher: BSpline solver Internal Geometry for poles

src/Mod/Sketcher/App/Constraint.h

@@ -67,7 +67,8 @@ enum InternalAlignmentType {
     HyperbolaMajor          = 5,
     HyperbolaMinor          = 6,
     HyperbolaFocus          = 7,
-    ParabolaFocus	    = 8
+    ParabolaFocus	        = 8,
+    BSplineControlPoint     = 9 // in this constraint "Third" is used to indicate the index of the control point (0-poles), it is not a GeoId
 };
 
 /// define if you want to use the end or start point

src/Mod/Sketcher/App/Sketch.cpp

@@ -1197,6 +1197,8 @@ int Sketch::addConstraint(const Constraint *constraint)
 	    case ParabolaFocus: 
                 rtn = addInternalAlignmentParabolaFocus(constraint->First,constraint->Second);
                 break;
+        case BSplineControlPoint:
+                rtn = addInternalAlignmentBSplineControlPoint(constraint->First,constraint->Second, constraint->Third);
             default:
                 break;
         }
@@ -2396,6 +2398,32 @@ int Sketch::addInternalAlignmentParabolaFocus(int geoId1, int geoId2)
     return -1;
 }
 
+int Sketch::addInternalAlignmentBSplineControlPoint(int geoId1, int geoId2, int poleindex)
+{
+    std::swap(geoId1, geoId2);
+
+    geoId1 = checkGeoId(geoId1);
+    geoId2 = checkGeoId(geoId2);
+
+    if (Geoms[geoId1].type != BSpline)
+        return -1;
+    if (Geoms[geoId2].type != Circle)
+        return -1;
+
+    int pointId1 = getPointId(geoId2, mid);
+
+    if (pointId1 >= 0 && pointId1 < int(Points.size())) {
+        GCS::Circle &c = Circles[Geoms[geoId2].index];
+
+        GCS::BSpline &b = BSplines[Geoms[geoId1].index];
+
+        int tag = ++ConstraintsCounter;
+        GCSsys.addConstraintInternalAlignmentBSplineControlPoint(b, c, poleindex, tag);
+        return ConstraintsCounter;
+    }
+    return -1;
+}
+
 double Sketch::calculateAngleViaPoint(int geoId1, int geoId2, double px, double py)
 {
     geoId1 = checkGeoId(geoId1);

src/Mod/Sketcher/App/Sketch.h

@@ -314,6 +314,7 @@ public:
     int addInternalAlignmentHyperbolaMinorDiameter(int geoId1, int geoId2);
     int addInternalAlignmentHyperbolaFocus(int geoId1, int geoId2);
     int addInternalAlignmentParabolaFocus(int geoId1, int geoId2);
+    int addInternalAlignmentBSplineControlPoint(int geoId1, int geoId2, int poleindex);
     //@}
 public:
     //This func is to be used during angle-via-point constraint creation. It calculates

src/Mod/Sketcher/App/planegcs/GCS.cpp

@@ -1007,6 +1007,12 @@ int System::addConstraintInternalAlignmentParabolaFocus(Parabola &e, Point &p1,
     return addConstraintEqual(e.focus1.y, p1.y, tagId);
 }
 
+int System::addConstraintInternalAlignmentBSplineControlPoint(BSpline &b, Circle &c, int poleindex, int tagId)
+{
+    addConstraintEqual(b.poles[poleindex].x, c.center.x, tagId);
+    return addConstraintEqual(b.poles[poleindex].y, c.center.y, tagId);
+}
+
 
 //calculates angle between two curves at point of their intersection p. If two
 //points are supplied, p is used for first curve and p2 for second, yielding a

src/Mod/Sketcher/App/planegcs/GCS.h

@@ -233,6 +233,7 @@ namespace GCS
         int addConstraintInternalAlignmentHyperbolaMinorDiameter(Hyperbola &e, Point &p1, Point &p2, int tagId=0);
         int addConstraintInternalAlignmentHyperbolaFocus(Hyperbola &e, Point &p1, int tagId=0);
         int addConstraintInternalAlignmentParabolaFocus(Parabola &e, Point &p1, int tagId=0);
+        int addConstraintInternalAlignmentBSplineControlPoint(BSpline &b, Circle &c, int poleindex, int tag=0);
 
         double calculateAngleViaPoint(Curve &crv1, Curve &crv2, Point &p);
         double calculateAngleViaPoint(Curve &crv1, Curve &crv2, Point &p1, Point &p2);