Fix 2dm coordinates saving

README.md

@@ -125,6 +125,7 @@ QGIS contains internal copy of MDAL library in following versions:
 | 3.30.0  | 1.0.2   | |
 | 3.36.0  | 1.1.0   | Mike21 format support read/write |
 | 3.38.0  | 1.2.0   | Groundwater / surface water meshes for 3Di format |
+| 3.42.0  | 1.3.0   | Fix 2dm format coordinates saving |
 
 versions `X.Y.9Z` are development versions or alpha/beta releases (e.g. `0.4.90`, `0.4.91`, ...)
 

mdal/frmts/mdal_2dm.cpp

@@ -402,7 +402,7 @@ void MDAL::Driver2dm::save( const std::string &fileName, const std::string &, MD
     for ( size_t j = 0; j < 2; ++j )
     {
       line.append( " " );
-      line.append( MDAL::coordinateToString( vertex[j] ) );
+      line.append( MDAL::doubleToString( vertex[j], 8, true ) );
     }
     line.append( " " );
     line.append( MDAL::doubleToString( vertex[2] ) );

mdal/mdal.cpp

@@ -21,7 +21,7 @@ static const char *EMPTY_STR = "";
 
 const char *MDAL_Version()
 {
-  return "1.2.0";
+  return "1.3.0";
 }
 
 MDAL_Status MDAL_LastStatus()

mdal/mdal_utils.cpp

@@ -837,10 +837,14 @@ std::string MDAL::coordinateToString( double coordinate, int precision )
   return returnString;
 }
 
-std::string MDAL::doubleToString( double value, int precision )
+std::string MDAL::doubleToString( double value, int precision, bool forceScientific )
 {
   std::ostringstream oss;
   oss.precision( precision );
+  if ( forceScientific )
+  {
+    oss.setf( std::ios::scientific );
+  }
   oss << value;
   return oss.str();
 }

mdal/mdal_utils.hpp

@@ -117,7 +117,8 @@ namespace MDAL
 
   //! Returns a string with scientific format
   //! precision is the number of signifiant digits
-  std::string doubleToString( double value, int precision = 6 );
+  //! forceScientific forces the scientific notation of the number even if not necessary
+  std::string doubleToString( double value, int precision = 6, bool forceScientific = false );
 
   /**
    * Splits by deliminer and skips empty parts.

tests/data/2dm/quad_and_triangle_scientific.2dm

@@ -0,0 +1,8 @@
+MESH2D
+ND 1 1.00000000e+03 2.00000000e+03 20
+ND 2 2.00000000e+03 2.00000000e+03 30
+ND 3 3.00000000e+03 2.00000000e+03 40
+ND 4 2.00000000e+03 3.00000000e+03 50
+ND 5 1.00000000e+03 3.00000000e+03 10
+E4Q 1 1 2 4 5
+E3T 2 2 3 4

tests/test_2dm.cpp

@@ -764,6 +764,31 @@ TEST( Mesh2DMTest, Save1DMeshToFile )
   );
 }
 
+TEST( Mesh2DMTest, QuadAndTriangleScientificNotationFile )
+{
+  std::string path = test_file( "/2dm/quad_and_triangle_scientific.2dm" );
+  EXPECT_EQ( MDAL_MeshNames( path.c_str() ), "2DM:\"" + path + "\"" );
+  MDAL_MeshH m_scientific = MDAL_LoadMesh( path.c_str() );
+  EXPECT_NE( m_scientific, nullptr );
+  MDAL_Status s = MDAL_LastStatus();
+  EXPECT_EQ( MDAL_Status::None, s );
+
+  int v_count = MDAL_M_vertexCount( m_scientific );
+  EXPECT_EQ( v_count, 5 );
+
+  int f_count = MDAL_M_faceCount( m_scientific );
+  EXPECT_EQ( 2, f_count );
+
+  path = test_file( "/2dm/quad_and_triangle.2dm" );
+  EXPECT_EQ( MDAL_MeshNames( path.c_str() ), "2DM:\"" + path + "\"" );
+  MDAL_MeshH m_not_scientific = MDAL_LoadMesh( path.c_str() );
+
+  compareMeshFrames( m_scientific, m_not_scientific );
+
+  MDAL_CloseMesh( m_scientific );
+  MDAL_CloseMesh( m_not_scientific );
+}
+
 int main( int argc, char **argv )
 {
   testing::InitGoogleTest( &argc, argv );