diff --git a/Apps/Examples/viewer.cpp b/Apps/Examples/viewer.cpp
index a566c24c360cd015d59064db50fa9954b176a7ff..551c7b4bd6090dbc6ac1dec5d6895189920b9cff 100644
--- a/Apps/Examples/viewer.cpp
+++ b/Apps/Examples/viewer.cpp
@@ -78,7 +78,9 @@ void Viewer::initGUI()
 
 void Viewer::cb_initGL()
 {
-	Utils::GLSLShader::setCurrentOGLVersion(2) ;
+	Utils::GLSLShader::setCurrentOGLVersion(3) ;
+	CGoGNout << "GL VERSION = "<< glGetString(GL_VERSION)<< CGoGNendl;
+	Utils::GLSLShader::areShadersSupported();
 
 	m_render = new Algo::Render::GL2::MapRender() ;
 	m_topoRender = new Algo::Render::GL2::TopoRenderMap<PFP>() ;
diff --git a/Apps/Examples/volumeExplorer.cpp b/Apps/Examples/volumeExplorer.cpp
index 023213b394aee82ff55742a078065d141fe5adff..208639175f49980c9b153a0c2bbe759ab8dd9f46 100644
--- a/Apps/Examples/volumeExplorer.cpp
+++ b/Apps/Examples/volumeExplorer.cpp
@@ -206,6 +206,8 @@ void MyQT::cb_initGL()
 {
 	// choose to use GL version 2
 	Utils::GLSLShader::setCurrentOGLVersion(2);
+	CGoGNout << "GL VERSION = "<< glGetString(GL_VERSION)<< CGoGNendl;
+	Utils::GLSLShader::areShadersSupported();
 
 	// create the renders
 	m_topo_render = new Algo::Render::GL2::Topo3RenderMap<PFP>();
diff --git a/include/Algo/Topo/Map2/uniformOrientation.hpp b/include/Algo/Topo/Map2/uniformOrientation.hpp
index ce016a0df623cfe24d3abd44551f548869a4f8f9..b52e1dc260042e763f2431a20216748f0c9bf606 100644
--- a/include/Algo/Topo/Map2/uniformOrientation.hpp
+++ b/include/Algo/Topo/Map2/uniformOrientation.hpp
@@ -106,7 +106,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 
 	DartMarker<MAP> cmf(map);
 
-	cmf.markOrbit<FACE>(faceSeed);
+	cmf.template markOrbit<FACE>(faceSeed);
 	propag.push_back(faceSeed);
 
 	while (!propag.empty() || !propag_inv.empty())
@@ -120,7 +120,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 			do
 			{
 				Dart e = map.phi2(d);
-				if (map.isBoundaryMarked2(e))
+				if (map.template isBoundaryMarked<2>(e))
 				{
 					e = findOtherInCouplesOfDarts(couples,d);
 					if (e!=NIL)
@@ -129,7 +129,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 						{
 							propag_inv.push_back(e);
 							face2invert.push_back(e);
-							cmf.markOrbit<FACE>(e);
+							cmf.template markOrbit<FACE>(e);
 						}
 						cmf.mark(map.phi2(e));// use cmf also to mark boudary cycle to invert
 					}
@@ -140,7 +140,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 					if (!cmf.isMarked(e))
 					{
 						propag.push_back(e);
-						cmf.markOrbit<FACE>(e);
+						cmf.template markOrbit<FACE>(e);
 					}
 				}
 				d= map.phi1(d);
@@ -157,7 +157,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 			do
 			{
 				Dart e = map.phi2(d);
-				if (map.isBoundaryMarked2(e))
+				if (map.template isBoundaryMarked<2>(e))
 				{
 					e = findOtherInCouplesOfDarts(couples,d);
 					if (e!=NIL)
@@ -165,7 +165,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 						if (!cmf.isMarked(e))
 						{
 							propag.push_back(e);
-							cmf.markOrbit<FACE>(e);
+							cmf.template markOrbit<FACE>(e);
 						}
 						cmf.mark(map.phi2(d));// use cmf also to mark boudary cycle to invert
 					}
@@ -176,7 +176,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 					{
 						propag_inv.push_back(e);
 						face2invert.push_back(e);
-						cmf.markOrbit<FACE>(e);
+						cmf.template markOrbit<FACE>(e);
 					}
 				}
 				d= map.phi1(d); // traverse all edges of face
@@ -195,7 +195,7 @@ void uniformOrientationCC(MAP& map, Dart faceSeed)
 		if (cmf.isMarked(e))	// check cmf for wrong orientation
 		{
 			reverse2MapFaceKeepPhi2<MAP>(map,e);
-			cmf.unmarkOrbit<FACE>(e);
+			cmf.template unmarkOrbit<FACE>(e);
 		}
 	}
 
diff --git a/src/Utils/GLSLShader.cpp b/src/Utils/GLSLShader.cpp
index 605eb66270eb76d5d9db32c2525f5de3916f4c07..5948a9d65da353eedfa774c11325251badc403d7 100644
--- a/src/Utils/GLSLShader.cpp
+++ b/src/Utils/GLSLShader.cpp
@@ -148,10 +148,35 @@ bool GLSLShader::areGeometryShadersSupported()
 
 bool GLSLShader::areShadersSupported()
 {
-	if ( ! glewGetExtension("GL_ARB_vertex_shader")) return false;
-	if ( ! glewGetExtension("GL_ARB_fragment_shader")) return false;
-	if ( ! glewGetExtension("GL_ARB_shader_objects")) return false;
-	if ( ! glewGetExtension("GL_ARB_shading_language_100")) return false;
+	if ( ! glewIsSupported("GL_ARB_vertex_shader"))
+	{
+		CGoGNerr << " vertex shaders not supported!" <<CGoGNendl;
+		return false;
+	}
+
+	if ( ! glewIsSupported("GL_ARB_fragment_shader"))
+	{
+		CGoGNerr << " fragment shaders not supported!" << CGoGNendl;
+		return false;
+	}
+
+	if ( ! glewIsSupported("GL_ARB_geometry_shader4"))
+	{
+		CGoGNerr << " geometry shaders not supported!" << CGoGNendl;
+		return false;
+	}
+
+	if ( ! glewIsSupported("GL_ARB_shader_objects"))
+	{
+		CGoGNerr << " shaders not supported!" << CGoGNendl;
+		return false;
+	}
+
+	if ( ! glewIsSupported("GL_ARB_shading_language_100"))
+	{
+		CGoGNerr << " GLSL no supported!" << CGoGNendl;
+		return false;
+	}
 
 	return true;
 }
@@ -399,7 +424,7 @@ bool GLSLShader::loadGeometryShaderSourceString( const char *geom_shader_source
 		*m_geom_shader_object=0;
 	}
 	/*** create shader object ***/
-	*m_geom_shader_object = glCreateShader(GL_GEOMETRY_SHADER_EXT);
+	*m_geom_shader_object = glCreateShader(GL_GEOMETRY_SHADER);
 
 	if( !*m_geom_shader_object )
 	{
diff --git a/src/Utils/Qt/qtgl.cpp b/src/Utils/Qt/qtgl.cpp
index 8b8214ecf106972d61bcb7da6c2c62cb09311db2..9d3b1021e2106eeee60c1497878cde9d80c85873 100644
--- a/src/Utils/Qt/qtgl.cpp
+++ b/src/Utils/Qt/qtgl.cpp
@@ -193,7 +193,6 @@ glm::vec3& GLWidget::getObjPos()
 
 void GLWidget::initializeGL()
 {
-	std::cout << "GL VERSION = "<< glGetString(GL_VERSION)<< std::endl;
 	glEnable(GL_DEPTH_TEST);
 
 	if (m_cbs)