Fix headless build

diff --git a/simgear/props/PropertyInterpolationMgr.cxx b/simgear/props/PropertyInterpolationMgr.cxx
index 4f217a7888254c64b1e2f6bc8343df1af9f68b66..3600bb02f1839d16be84a72c5c7d589c503f4887 100644 (file)
--- a/simgear/props/PropertyInterpolationMgr.cxx
+++ b/simgear/props/PropertyInterpolationMgr.cxx
@@ -19,12 +19,13 @@
 #include "PropertyInterpolationMgr.hxx"
 #include "PropertyInterpolator.hxx"
 
+#include <simgear_config.h>
+
 #ifndef SIMGEAR_HEADLESS
 # include <simgear/scene/util/ColorInterpolator.hxx>
 #endif
 
 #include <simgear/props/props.hxx>
-#include <simgear_config.h>
 
 #include <algorithm>