[TD] Move Circulation method to DrawUtil

src/Mod/TechDraw/App/Cosmetic.cpp

@@ -976,24 +976,6 @@ std::pair<Base::Vector3d, Base::Vector3d> CenterLine::calcEndPoints(DrawViewPart
     return result;
 }
 
-bool CenterLine::Circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C)
-{
-    // the determinant of this matrix calculates the area of a triangle, see
-    // https://en.wikipedia.org/wiki/Triangle#Using_coordinates
-    // a 3x3 matrix would also do the job, but FC supports only 4x4 matrixes
-    Base::Matrix4D CircMatrix(
-        A.x, A.y, 1, 0,
-        B.x, B.y, 1, 0,
-        C.x, C.y, 1, 0,
-        0, 0, 0, 1);
-
-    // the sign delivers the dicrection of travel along the triangle edges
-    if (CircMatrix.determinant() > 0)
-        return true;
-    else
-        return false;
-}
-
 std::pair<Base::Vector3d, Base::Vector3d> CenterLine::calcEndPoints2Lines(DrawViewPart* partFeat,
                                                       std::vector<std::string> edgeNames, 
                                                       int mode, double ext,
@@ -1042,7 +1024,7 @@ std::pair<Base::Vector3d, Base::Vector3d> CenterLine::calcEndPoints2Lines(DrawVi
     // https://wiki.freecadweb.org/File:TD-CenterLineFlip.png for an illustration of the problem.
     // Thus we test this by a circulation test, see this post for a brief explanation:
     // https://forum.freecadweb.org/viewtopic.php?p=505733#p505615
-    if (Circulation(l1p1, l1p2, l2p1) != Circulation(l1p2, l2p2, l2p1)) {
+    if (DrawUtil::circulation(l1p1, l1p2, l2p1) != DrawUtil::circulation(l1p2, l2p2, l2p1)) {
         Base::Vector3d temp; // reverse line 1
         temp = l1p1;
         l1p1 = l1p2;

src/Mod/TechDraw/App/Cosmetic.h

@@ -220,7 +220,6 @@ public:
                                           int mode, double ext,
                                           double m_hShift, double m_vShift,
                                           double rotate);
-    static bool Circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C);
     static std::pair<Base::Vector3d, Base::Vector3d> calcEndPoints2Lines(
                                           TechDraw::DrawViewPart* partFeat,
                                           std::vector<std::string> faceNames,

src/Mod/TechDraw/App/DrawUtil.cpp

@@ -789,6 +789,15 @@ Base::Vector3d DrawUtil::getFaceCenter(TopoDS_Face f)
     return v;
 }
 
+// test the circulation of the triangle A-B-C
+bool DrawUtil::circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C) 
+{
+    if (A.x * B.y + A.y * C.x + B.x * C.y - C.x * B.y - C.y * A.x - B.x * A.y > 0.0)
+        return true;
+    else
+        return false;
+}
+
 // Supplementary mathematical functions
 // ====================================
 

src/Mod/TechDraw/App/DrawUtil.h

@@ -121,6 +121,7 @@ class TechDrawExport DrawUtil {
         static PyObject* colorToPyTuple(App::Color color);
         static bool isCrazy(TopoDS_Edge e);
         static Base::Vector3d getFaceCenter(TopoDS_Face f);
+        static bool circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C);
 
         // Supplementary mathematical functions
         static int sgn(double x);

src/Mod/TechDraw/Gui/CommandExtensionPack.cpp

@@ -84,7 +84,6 @@ namespace TechDrawGui {
 
     //internal helper functions
     lineAttributes& _getActiveLineAttributes();
-    bool _circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C);
     Base::Vector3d _circleCenter(Base::Vector3d p1, Base::Vector3d p2, Base::Vector3d p3);
     void _createThreadCircle(std::string Name, TechDraw::DrawViewPart* objFeat, float factor);
     void _createThreadLines(std::vector<std::string> SubNames, TechDraw::DrawViewPart* objFeat, float factor);
@@ -1845,14 +1844,6 @@ namespace TechDrawGui {
         return Base::Vector3d(c.x, c.y, 0.0);
     }
 
-    bool _circulation(Base::Vector3d A, Base::Vector3d B, Base::Vector3d C) {
-        // test the circulation of the triangle A-B-C
-        if (A.x * B.y + A.y * C.x + B.x * C.y - C.x * B.y - C.y * A.x - B.x * A.y > 0.0)
-            return true;
-        else
-            return false;
-    }
-
     void _createThreadCircle(std::string Name, TechDraw::DrawViewPart* objFeat, float factor) {
         // create the 3/4 arc symbolizing a thread from top seen
         double scale = objFeat->getScale();
@@ -1890,7 +1881,7 @@ namespace TechDrawGui {
                 Base::Vector3d end0 = line0->points.at(1);
                 Base::Vector3d start1 = line1->points.at(0);
                 Base::Vector3d end1 = line1->points.at(1);
-                if (_circulation(start0, end0, start1) != _circulation(end0, end1, start1)) {
+                if (DrawUtil::circulation(start0, end0, start1) != DrawUtil::circulation(end0, end1, start1)) {
                     Base::Vector3d help1 = start1;
                     Base::Vector3d help2 = end1;
                     start1 = help2;