added specular, ambient light,...

need to fix the texutre gamma correction,
look at the todos

QtMeshViewer/Header/OglViewerWidget.h

@@ -39,7 +39,9 @@ private:
 
 	struct {
 		QVector3D position = { 1,1,1 };
-		QVector3D intensities = { 1,0.25,0.25 };
+		QVector3D intensities = { 1,1,1 };
+		float attenuationFactor = 0.2f;
+		float ambientCoefficient = 0.005f;
 	} m_light;
 
 	QOpenGLShaderProgram m_program;