Merge branch 'opengl_glvnd_preferences' into 'develop'

BUG: Be compliant with new cmake policy CMP0072 with cmake > 3.11

See merge request orfeotoolbox/otb!155

CMakeLists.txt

@@ -23,7 +23,8 @@ cmake_minimum_required(VERSION 3.1.0)
 foreach(p
     CMP0025 # CMake 3.0
     CMP0042 # CMake 3.0
-    CMP0058
+    CMP0058 # CMake 3.3
+    CMP0072 # CMake 3.11
     )
   if(POLICY ${p})
     cmake_policy(SET ${p} NEW)

Modules/ThirdParty/OpenGL/otb-module-init.cmake

@@ -18,7 +18,7 @@
 # limitations under the License.
 #
 
-#detection of OpenGL is apply is bit tricy as we deactivate
+#detection of OpenGL is apply is a bit tricky as we deactivate
 #framework on OSX globally. see mantis #1193
 if(APPLE)
   set( OPENGL_FOUND FALSE )
@@ -38,7 +38,7 @@ if(APPLE)
     PATHS "/System/Library/Frameworks/"
     DOC "OpenGL lib for OSX"
     )
-  
+
   find_library(
     OPENGL_glu_LIBRARY AGL
     PATHS "/System/Library/Frameworks/"
@@ -62,6 +62,7 @@ if(APPLE)
     )
 else(APPLE)
   find_package(OpenGL REQUIRED)
+
   mark_as_advanced(OPENGL_INCLUDE_DIR)
   mark_as_advanced(OPENGL_LIBRARIES)
 endif(APPLE)
@@ -73,11 +74,15 @@ if(NOT OPENGL_INCLUDE_DIR)
   endif()
 endif()
 
-if(NOT OPENGL_gl_LIBRARY)
-  message(FATAL_ERROR "Could not find OpenGL (missing: OPENGL_gl_LIBRARY")
+# For CMake > 3.11 the default GLVND instead of legacy GL library
+# Test both of them to 
+# FIXME: As stated in CMake documentation we should use the OpenGL::* import targets instead available
+# It should be done when OTB will increase CMake minimum version to 3.X
+# See: https://cmake.org/cmake/help/v3.11/module/FindOpenGL.html
+if(NOT OPENGL_gl_LIBRARY AND NOT OPENGL_opengl_LIBRARY)
+  message(FATAL_ERROR "Could not find OpenGL (missing: OPENGL_gl_LIBRARY or OPENGL_opengl_LIBRARY")
 endif()
 
 if(NOT OPENGL_glu_LIBRARY)
   message(FATAL_ERROR "Could not find OpenGL (missing: OPENGL_glu_LIBRARY")
 endif()
-