[graf3d] Fix errors and warnings due to TGLWSIncludes.h

The TGLWSIncludes.h header is being removed from the public interface
in v6.40. Due to using a >= instead of =, it was causing a compiler
error already in v6.38, where it was supposed to raise only a warning.

Now, the public header unconditionally raises a warning in Linux and Mac,
and a local version of this header is added to graf3d/src, which allows
for ROOT to compile without warnings.

Author: hageboeck

graf3d/gl/CMakeLists.txt

@@ -232,9 +232,6 @@ else()
   target_include_directories(RGL PRIVATE ${GL2PS_INCLUDE_DIRS})
 endif()
 
-# Remove when not needed anymore in the ROOT 6.40 development cycle
-target_compile_definitions(RGL PRIVATE _ROOT_GL_BUILDS_ITSELF)
-
 if(MSVC AND builtin_glew)
   target_compile_definitions (RGL PRIVATE "GLEW_STATIC")
 endif()

graf3d/gl/inc/TGLWSIncludes.h

@@ -18,17 +18,9 @@
 
 // This header is deprecated according to
 // https://its.cern.ch/jira/browse/ROOT-9807
-// In the 6.38 release, our users will get a warning, and then in 6.40 we
-// remove this header. Conditional on the ROOT version, this header will give
-// an error on inclusion to remind us to move it. Remove also the
-// _ROOT_GL_BUILDS_ITSELF definition from the CMakeLists.txt then.
-#if ROOT_VERSION_CODE >= ROOT_VERSION(6, 38, 00)
-#error "Header should be moved outside of the public ROOT interface now"
-#else
-#ifndef _ROOT_GL_BUILDS_ITSELF
+#ifndef _WIN32
 #warning "The TGLWSIncludes.h header is deprecated and will be removed in ROOT 6.40"
 #endif
-#endif
 
 
 #include "RConfigure.h"

graf3d/gl/src/TGLContextPrivate.h

@@ -7,7 +7,7 @@
 #include <map>
 
 #include "TGLIncludes.h"
-#include "TGLWSIncludes.h"
+#include "TGLWSIncludes_local.h"
 #include "TGLContext.h"
 #include "RConfigure.h"
 #include "GuiTypes.h"

graf3d/gl/src/TGLFormat.cxx

@@ -14,7 +14,7 @@
 #include <set>
 
 #include "TGLFormat.h"
-#include "TGLWSIncludes.h"
+#include "TGLWSIncludes_local.h"
 #include "TGLWidget.h"
 
 #include "TEnv.h"

graf3d/gl/src/TGLWSIncludes_local.h

@@ -0,0 +1,32 @@
+// @(#)root/gl:$Id$
+// Authors:  Timur and Matevz, May 2008
+
+/*************************************************************************
+ * Copyright (C) 1995-2004, Rene Brun and Fons Rademakers.               *
+ * All rights reserved.                                                  *
+ *                                                                       *
+ * For the licensing terms see $ROOTSYS/LICENSE.                         *
+ * For the list of contributors see $ROOTSYS/README/CREDITS.             *
+ *************************************************************************/
+
+// Window-system specific GL includes.
+// Inclusion should only be necessary in in low-level system files.
+
+#ifndef ROOT_TGLWSIncludes_local
+#define ROOT_TGLWSIncludes_local
+
+#include "RConfigure.h"
+#include "TGLIncludes.h"
+
+#if defined(WIN32)
+#  include <GL/wglew.h>
+#else
+#  if defined(__APPLE__) && !defined(R__HAS_COCOA)
+#    define GLEW_APPLE_GLX
+#  endif
+#  if !defined(R__HAS_COCOA)
+#    include <GL/glxew.h>
+#  endif
+#endif
+
+#endif

graf3d/gl/src/TGLWidget.cxx

@@ -20,7 +20,7 @@
 
 #include "TGLWidget.h"
 #include "TGLIncludes.h"
-#include "TGLWSIncludes.h"
+#include "TGLWSIncludes_local.h"
 #include "TGLUtil.h"
 #include "TGLEventHandler.h"
 #include "RConfigure.h"