added LoadCSVField function

wrap/io_trimesh/import_field.h

@@ -335,6 +335,38 @@ public:
         return true;
     }
 
+    static bool LoadCSVField(MeshType &mesh,
+                             const std::string &field_1,
+                             const std::string &field_2,
+                             bool Normalize=true)
+    {
+        FILE *f1=NULL;
+        FILE *f2=NULL;
+        f1=fopen(field_1.c_str(),"rt");
+        if(f1==NULL)return false;
+        f2=fopen(field_2.c_str(),"rt");
+        if(f2==NULL)return false;
+        for (size_t i=0;i<mesh.face.size();i++)
+        {
+            float Xdir,Ydir,Zdir;
+            fscanf(f1,"%f,%f,%f\n",&Xdir,&Ydir,&Zdir);
+            mesh.face[i].PD1()=CoordType(Xdir,Ydir,Zdir);
+            //std::cout<<Xdir<<" "<<Ydir<<std::endl;
+            fscanf(f2,"%f,%f,%f\n",&Xdir,&Ydir,&Zdir);
+            mesh.face[i].PD2()=CoordType(Xdir,Ydir,Zdir);
+            //set the quality as force Value
+            if (Normalize)
+            {
+                mesh.face[i].PD1().Normalize();
+                mesh.face[i].PD2().Normalize();
+            }
+        }
+
+        //then color by quality
+        fclose(f1);
+        fclose(f2);
+    }
+
 }; // end class