Fix MSVC build

diff --git a/simgear/scene/tgdb/SGReaderWriterBTG.cxx b/simgear/scene/tgdb/SGReaderWriterBTG.cxx
index 05f6d74ff713741696400c2b371c6f20781231d2..a3a0fe5c45480b6d38bda3edebcd9953d2bd1d28 100644 (file)
--- a/simgear/scene/tgdb/SGReaderWriterBTG.cxx
+++ b/simgear/scene/tgdb/SGReaderWriterBTG.cxx
@@ -15,11 +15,16 @@
 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //
 
+#ifdef HAVE_CONFIG_H
+#  include <simgear_config.h>
+#endif
+
 #include <osgDB/FileNameUtils>
 #include <osgDB/Registry>
 
 #include <simgear/scene/model/ModelRegistry.hxx>
 #include <simgear/scene/util/SGReaderWriterOptions.hxx>
+#include <simgear/math/SGMath.hxx>
 
 #include "SGReaderWriterBTG.hxx"
 #include "obj.hxx"