COMP: patch paraview 5.0.1 for building with osmesa

- reference: https://gitlab.kitware.com/vtk/vtk/merge_requests/1642

etc/patches/paraview-5.0.1

@@ -85,3 +85,137 @@
 
  set (xslt_xml)
 
+--- ParaView-5.0.1/VTK/CMake/vtkOpenGL.cmake.orig	2016-03-28 17:07:10.000000000 +0200
++++ ParaView-5.0.1/VTK/CMake/vtkOpenGL.cmake	2017-01-19 10:23:19.170743269 +0100
+@@ -19,9 +19,11 @@
+ # OSMesa logic for offscreen mesa rendering.
+ option(VTK_OPENGL_HAS_OSMESA
+   "The OpenGL library being used supports off screen Mesa calls" OFF)
++
+ # EGL offscreen rendering
+ option(VTK_USE_OFFSCREEN_EGL
+   "Use EGL for OpenGL client API for offscreen rendering." OFF)
++
+ set(VTK_EGL_DEVICE_INDEX 0 CACHE STRING
+   "Index of the EGL device (graphics card) to use.")
+
+@@ -33,21 +35,26 @@
+ endif()
+
+ option(VTK_USE_OFFSCREEN "Use off screen calls by default" OFF)
++
+ unset(VTK_CAN_DO_OFFSCREEN)
++unset(VTK_CAN_DO_ONSCREEN)
++
+ if(VTK_OPENGL_HAS_OSMESA OR WIN32 OR VTK_USE_OFFSCREEN_EGL)
+   set(VTK_CAN_DO_OFFSCREEN 1)
+ endif()
++
+ if(VTK_USE_X OR VTK_USE_COCOA OR WIN32 OR ANDROID OR APPLE_IOS)
+-  set(VTK_USE_OSMESA FALSE)
++  set(VTK_USE_OSMESA ${VTK_OPENGL_HAS_OSMESA})
+   if (VTK_USE_OFFSCREEN_EGL)
+     message(FATAL_ERROR "VTK_USE_OFFSCREEN_EGL set together with one of ("
+       "VTK_USE_X, VTK_USE_COCOA, WIN32, ANDROID OR APPLE_IOS). "
+       "You cannot use both offscreen and one of the listed windowing systems.")
+   endif()
++  set(VTK_CAN_DO_ONSCREEN 1)
+ elseif(VTK_USE_OFFSCREEN_EGL)
+   set(VTK_USE_OSMESA FALSE)
+ else()
+-  set(VTK_USE_OSMESA TRUE)
++  set(VTK_USE_OSMESA ${VTK_OPENGL_HAS_OSMESA})
+ endif()
+
+ mark_as_advanced(VTK_USE_X VTK_OPENGL_HAS_OSMESA VTK_USE_OFFSCREEN_EGL
+@@ -56,10 +63,17 @@
+ if(VTK_USE_OSMESA)
+   find_package(OSMesa REQUIRED)
+   include_directories(SYSTEM ${OSMESA_INCLUDE_DIR})
+-elseif(VTK_USE_OFFSCREEN_EGL)
++endif()
++
++if(VTK_USE_OFFSCREEN_EGL)
+     find_package(EGL REQUIRED)
+     include_directories(SYSTEM ${EGL_INCLUDE_DIR})
+-else()
++endif()
++
++if(VTK_CAN_DO_ONSCREEN)
++  # OpenGL libraries are explicity needed if windowing system-based API is being
++  # used. Otherwise, if only doing OFFSCREEN, the GL API is provided by the
++  # offscreen library be it EGL or OSMESA.
+   find_package(OpenGL REQUIRED)
+   include_directories(SYSTEM ${OPENGL_INCLUDE_DIR})
+   if(APPLE)
+@@ -83,9 +97,11 @@
+ function(vtk_opengl_link target)
+   if(VTK_USE_OSMESA)
+     vtk_module_link_libraries(${target} LINK_PRIVATE ${OSMESA_LIBRARY})
+-  elseif(VTK_USE_OFFSCREEN_EGL)
++  endif()
++  if(VTK_USE_OFFSCREEN_EGL)
+     vtk_module_link_libraries(${target} LINK_PRIVATE ${EGL_LIBRARIES})
+-  else()
++  endif()
++  if(VTK_CAN_DO_ONSCREEN)
+     vtk_module_link_libraries(${target} LINK_PRIVATE ${OPENGL_LIBRARIES})
+   endif()
+ endfunction()
+--- ParaView-5.0.1/VTK/Rendering/OpenGL2/vtkXOpenGLRenderWindow.cxx.orig	2016-03-28 17:07:10.000000000 +0200
++++ ParaView-5.0.1/VTK/Rendering/OpenGL2/vtkXOpenGLRenderWindow.cxx	2017-01-19 15:24:21.783214877 +0100
+@@ -30,10 +30,25 @@
+ typedef ptrdiff_t GLsizeiptr;
+ #include "GL/glx.h"
+
++
++#ifndef GLAPI
++#define GLAPI extern
++#endif
++
++#ifndef GLAPIENTRY
++#define GLAPIENTRY
++#endif
++
++#ifndef APIENTRY
++#define APIENTRY GLAPIENTRY
++#endif
++
+ #include "vtkToolkits.h"
+
+ #ifdef VTK_USE_OSMESA
+ #include <GL/osmesa.h>
++
++typedef OSMesaContext GLAPIENTRY (*OSMesaCreateContextAttribs_func)( const int *attribList, OSMesaContext sharelist );
+ #endif
+
+ #include "vtkCommand.h"
+@@ -757,6 +772,28 @@
+       this->Size[1] = height;
+       this->OwnWindow = 1;
+       }
++
++#if (OSMESA_MAJOR_VERSION * 100 + OSMESA_MINOR_VERSION >= 1102) && defined(OSMESA_CONTEXT_MAJOR_VERSION)
++    static const int attribs[] = {
++       OSMESA_FORMAT, OSMESA_RGBA,
++       OSMESA_DEPTH_BITS, 32,
++       OSMESA_STENCIL_BITS, 0,
++       OSMESA_ACCUM_BITS, 0,
++       OSMESA_PROFILE, OSMESA_CORE_PROFILE,
++       OSMESA_CONTEXT_MAJOR_VERSION, 3,
++       OSMESA_CONTEXT_MINOR_VERSION, 2,
++       0 };
++
++    OSMesaCreateContextAttribs_func OSMesaCreateContextAttribs =
++       (OSMesaCreateContextAttribs_func)
++       OSMesaGetProcAddress("OSMesaCreateContextAttribs");
++
++    if (OSMesaCreateContextAttribs != NULL)
++    {
++      this->Internal->OffScreenContextId = OSMesaCreateContextAttribs(attribs, NULL);
++    }
++#endif
++    // if we still have no context fall back to the generic signature
+     if (!this->Internal->OffScreenContextId)
+       {
+       this->Internal->OffScreenContextId = OSMesaCreateContext(GL_RGBA, NULL);