ENH: meshTools: Add functions to write lines and vectors to .obj files

src/meshTools/meshTools/meshTools.C

@@ -215,6 +215,39 @@ void Foam::meshTools::writeOBJ
 }
 
 
+void Foam::meshTools::writeOBJ
+(
+    Ostream& os,
+    const point& p1,
+    const point& p2,
+    label& count
+)
+{
+    os << "v" << ' ' << p1.x() << ' ' << p1.y() << ' ' << p1.z() << endl;
+    os << "v" << ' ' << p2.x() << ' ' << p2.y() << ' ' << p2.z() << endl;
+
+    os << "l" << " " << (count + 1) << " " << (count + 2) << endl;
+    
+    count += 2;
+}
+
+
+void Foam::meshTools::writeOBJ
+(
+    Ostream& os,
+    const point& p1,
+    const point& p2
+)
+{
+    os << "v" << ' ' << p1.x() << ' ' << p1.y() << ' ' << p1.z() << endl;
+
+    os << "vn"
+        << ' ' << p2.x() - p1.x()
+        << ' ' << p2.y() - p1.y()
+        << ' ' << p2.z() - p1.z() << endl;
+}
+
+
 void Foam::meshTools::writeOBJ
 (
     Ostream& os,

src/meshTools/meshTools/meshTools.H

@@ -107,6 +107,24 @@ namespace meshTools
             const point& pt
         );
 
+        //- Write obj representation of a line connecting two points
+        //  Need to keep track of points that have been added. count starts at 0
+        void writeOBJ
+        (
+            Ostream& os,
+            const point& p1,
+            const point& p2,
+            label& count
+        );
+
+        //- Write obj representation of a point p1 with a vector from p1 to p2
+        void writeOBJ
+        (
+            Ostream& os,
+            const point& p1,
+            const point& p2
+        );
+
         //- Write obj representation of faces subset
         void writeOBJ
         (