X11:X11 target not found when uprgrading from vtk 8 to 9 on Rocky9 linux

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I’m trying to use the native vtk install on Rocky9 Linux. Not sure I understand why /lib64/cmake/vtk/VTK-vtk-module-find-packages.cmake apparently defines find_package(X11) twice - see listing below. In between there is some logic relating to RenderingOpenGL2 which is the module I’m trying to add that causes the X11 not found error to re-appear.

I thought I saw a posting that said it is preferable now to not use VTK_LIBRARIES when linking and instead, spell out the individual VTK components to link against for each application. Just wondering if that more explicit/specific instruction about what to link against might remedy this issue.

find_package(X11
  
  
  
  ${_vtk_module_find_package_quiet}
  ${_vtk_module_find_package_required}
  COMPONENTS          
  OPTIONAL_COMPONENTS )
if (NOT X11_FOUND AND _vtk_module_find_package_fail_if_not_found)
  if (NOT ${CMAKE_FIND_PACKAGE_NAME}_FIND_QUIETLY)
    message(STATUS
      "Could not find the ${CMAKE_FIND_PACKAGE_NAME} package due to a "
      "missing dependency: X11")
  endif ()
  set("${CMAKE_FIND_PACKAGE_NAME}_RenderingOpenGL2_FOUND" 0)
  list(APPEND "${CMAKE_FIND_PACKAGE_NAME}_RenderingOpenGL2_NOT_FOUND_MESSAGE"
    "Failed to find the X11 package.")
endif ()
endif ()

unset(_vtk_module_find_package_fail_if_not_found)
unset(_vtk_module_find_package_enabled)
unset(_vtk_module_find_package_required)

set(_vtk_module_find_package_enabled OFF)
set(_vtk_module_find_package_is_required OFF)
set(_vtk_module_find_package_fail_if_not_found OFF)
if (_vtk_module_find_package_components)
if ("RenderingUI" IN_LIST _vtk_module_find_package_components)
  set(_vtk_module_find_package_enabled ON)
  if ("RenderingUI" IN_LIST _vtk_module_find_package_components_required)
    set(_vtk_module_find_package_is_required "${${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED}")
    set(_vtk_module_find_package_fail_if_not_found ON)
  endif ()
endif ()
else ()
set(_vtk_module_find_package_enabled ON)
set(_vtk_module_find_package_is_required "${${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED}")
set(_vtk_module_find_package_fail_if_not_found ON)
endif ()

if (_vtk_module_find_package_enabled)
set(_vtk_module_find_package_required)
if (_vtk_module_find_package_is_required)
  set(_vtk_module_find_package_required REQUIRED)
endif ()

find_package(X11
  
  
  
  ${_vtk_module_find_package_quiet}
  ${_vtk_module_find_package_required}
  COMPONENTS          
  OPTIONAL_COMPONENTS )
if (NOT X11_FOUND AND _vtk_module_find_package_fail_if_not_found)
  if (NOT ${CMAKE_FIND_PACKAGE_NAME}_FIND_QUIETLY)
    message(STATUS
      "Could not find the ${CMAKE_FIND_PACKAGE_NAME} package due to a "
      "missing dependency: X11")
  endif ()
  set("${CMAKE_FIND_PACKAGE_NAME}_RenderingUI_FOUND" 0)
  list(APPEND "${CMAKE_FIND_PACKAGE_NAME}_RenderingUI_NOT_FOUND_MESSAGE"
    "Failed to find the X11 package.")
endif ()
endif ()