Prefer pkgconfig for QGLViewer, easier than findcmake file and it avoids call of 3rd library
diff --git a/octovis/CMakeLists.txt b/octovis/CMakeLists.txt
index 84fa367..bc54f36 100644
--- a/octovis/CMakeLists.txt
+++ b/octovis/CMakeLists.txt
@@ -77,7 +77,8 @@ endif(NOT OCTOVIS_QT5)
 IF (OpenGL-NOTFOUND OR Qt4-NOTFOUND)
 	MESSAGE ( "OpenGL and QT4 are required for octovis but could not be found.")
 ELSE()
-	FIND_PACKAGE(QGLViewer)
+	FIND_PACKAGE(PkgConfig REQUIRED)
+	pkg_check_modules(QGLViewer libQGLViewer)
 	IF(QGLViewer_FOUND)
 	  SET( BUILD_VIEWER 1)
 	ELSE()
diff --git a/octovis/CMakeLists_src.txt b/octovis/CMakeLists_src.txt
index 35bc1f2..85fd61a 100644
--- a/octovis/CMakeLists_src.txt
+++ b/octovis/CMakeLists_src.txt
@@ -57,11 +57,8 @@ else(OCTOVIS_QT5)
   QT4_ADD_RESOURCES(viewer_RES src/icons.qrc)
 endif(OCTOVIS_QT5)
 
-#found QGLViewer lib dir
-link_directories(${QGLViewer_LIBRARY_DIR})
-
 INCLUDE_DIRECTORIES(
-  ${QGLViewer_INCLUDE_DIR}
+  ${QGLViewer_INCLUDE_DIRS}
 )
 
 SET(viewer_MOC_HDRS