Delete deprecated TGLIncludes.h public header

Delete a deprecated header that was kept for backwards compatibility,
and mention the removal of GLEW headers done in f7eda99 in the
release notes.

Author: guitargeek

README/ReleaseNotes/v640/index.md

@@ -36,6 +36,8 @@ The following people have contributed to this new version:
 
 * The `TObject` equality operator pythonization (`TObject.__eq__`) that was deprecated in ROOT 6.38 and scheduled for removal in ROOT 6.40 is removed
 * Comparing C++ `nullptr` objects with `None` in Python now raises a `TypeError`, as announced in the ROOT 6.38 release notes. Use truth-value checks like `if not x` or `x is None` instead.
+* The `TGLIncludes.h` and `TGLWSIncludes.h` that were deprecated in ROOT 6.38 and scheduled for removal are gone now. Please include your required headers like `<GL/gl.h>` or `<GL/glu.h>` directly.
+* The GLEW headers (`GL/eglew.h`, `GL/glew.h`, `GL/glxew.h`, and `GL/wglew.h`) that were installed when building ROOT with `builtin_glew=ON` are no longer installed. This is done because ROOT is moving away from GLEW for loading OpenGL extensions.
 
 ## Build System
 

graf3d/eve/CMakeLists.txt

@@ -229,7 +229,7 @@ if(MSVC)
       OpenGL::GL
       OpenGL::GLU
       ${FTGL_LIBRARIES}
-      RGlew
+      GLEW::GLEW
     DEPENDENCIES
       Core
       EG
@@ -264,7 +264,7 @@ else()
       OpenGL::GL
       OpenGL::GLU
       ${FTGL_LIBRARIES}
-      RGlew
+      GLEW::GLEW
     DEPENDENCIES
       Core
       EG

graf3d/eve/src/TGLIncludes.h

@@ -0,0 +1,5 @@
+#ifdef WIN32
+#include "Windows4Root.h"
+#endif
+
+#include <GL/glew.h>

graf3d/ftgl/CMakeLists.txt

@@ -40,7 +40,7 @@ ROOT_LINKER_LIBRARY(FTGL
     OpenGL::GLU
     ${FREETYPE_LIBRARIES}
     ZLIB::ZLIB
-    RGlew
+    GLEW::GLEW
   BUILTINS
     FREETYPE
 )

graf3d/gl/CMakeLists.txt

@@ -210,7 +210,7 @@ ROOT_STANDARD_LIBRARY_PACKAGE(RGL
     ${FTGL_LIBRARIES}
     ${GL2PS_LIBRARIES}
     ${X11_LIBRARIES}
-    RGlew
+    GLEW::GLEW
   DEPENDENCIES
     Hist
     Gui

graf3d/gl/src/TGLIncludes.h

@@ -0,0 +1,5 @@
+#ifdef WIN32
+#include "Windows4Root.h"
+#endif
+
+#include <GL/glew.h>

graf3d/gl/src/TPointSet3DGL.cxx

@@ -18,7 +18,7 @@
 
 #include <TGLRnrCtx.h>
 #include <TGLSelectRecord.h>
-#include <TGLIncludes.h>
+#include "TGLIncludes.h"
 
 /** \class TPointSet3DGL
 \ingroup opengl

graf3d/gl/src/gl2ps/gl2ps.h

@@ -38,7 +38,7 @@
 #include <cstdio>
 #include <cstdlib>
 
-#include <TGLIncludes.h>
+#include "../TGLIncludes.h"
 
 #define GL2PSDLL_API