vtk-m2/CMake/VTKmRenderingContexts.cmake
Kenneth Moreland 96ff3a5343 Find OpenGL libraries in external projects
Previously when an external project loaded VTK-m with find_package(VTKm)
and then tried to use anything with OpenGL, you would get compiler (and
probably linker) errors. The problem was that
VTKmRenderingContexts.cmake skipped over the loading of OpenGL libraries
because the vtkm_rendering_gl_context target was imported before this
code was ever called. Correct the problem by going through the motions
of checking OpenGL every time.
2018-04-19 19:41:46 -06:00

119 lines
3.7 KiB
CMake

##============================================================================
## Copyright (c) Kitware, Inc.
## All rights reserved.
## See LICENSE.txt for details.
## This software is distributed WITHOUT ANY WARRANTY; without even
## the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
## PURPOSE. See the above copyright notice for more information.
##
## Copyright 2014 National Technology & Engineering Solutions of Sandia, LLC (NTESS).
## Copyright 2014 UT-Battelle, LLC.
## Copyright 2014 Los Alamos National Security.
##
## Under the terms of Contract DE-NA0003525 with NTESS,
## the U.S. Government retains certain rights in this software.
##
## Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
## Laboratory (LANL), the U.S. Government retains certain rights in
## this software.
##============================================================================
#-----------------------------------------------------------------------------
# find OpenGL and supporting libraries provided to make using VTK-m easier
# for consumers.
#
# vtkm_find_gl(
# REQUIRED [GL|GLUT|GLEW]
# OPTIONAL [GL|GLUT|GLEW]
# QUIET [ON/OFF]
# )
#
# Imports everything as imported modules with the following names:
# - GLUT::GLUT
# - GLEW::GLEW
# - OpenGL::GL
# For OpenGL Will also provide the more explicit targets of:
# - OpenGL::OpenGL
# - OpenGL::GLU
# - OpenGL::GLX
# - OpenGL::EGL
function(vtkm_find_gl)
set(oneValueArgs QUIET)
set(multiValueArgs REQUIRED OPTIONAL)
cmake_parse_arguments(find_gl
"${options}" "${oneValueArgs}" "${multiValueArgs}"
${ARGN}
)
set(QUIETLY )
if(find_gl_QUIET)
set(QUIETLY "QUIET")
endif()
foreach(item ${find_gl_REQUIRED})
set(${item}_REQUIRED "REQUIRED")
set(DO_${item}_FIND TRUE)
endforeach()
foreach(item ${find_gl_OPTIONAL})
set(DO_${item}_FIND TRUE)
endforeach()
#Find GL
if(DO_GL_FIND AND NOT TARGET OpenGL::GL)
if(CMAKE_VERSION VERSION_LESS 3.10)
find_package(OpenGL ${GL_REQUIRED} ${QUIETLY} MODULE)
else()
#clunky but we need to make sure we use the upstream module if it exists
set(orig_CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH})
set(CMAKE_MODULE_PATH "")
find_package(OpenGL ${GL_REQUIRED} ${QUIETLY} MODULE)
set(CMAKE_MODULE_PATH ${orig_CMAKE_MODULE_PATH})
endif()
endif()
#Find GLEW
if(DO_GLEW_FIND AND NOT TARGET GLEW::GLEW)
find_package(GLEW ${GLEW_REQUIRED} ${QUIETLY})
endif()
if(DO_GLUT_FIND AND NOT TARGET GLUT::GLUT)
find_package(GLUT ${GLUT_REQUIRED} ${QUIETLY})
endif()
endfunction()
#-----------------------------------------------------------------------------
if(VTKm_ENABLE_GL_CONTEXT OR
VTKm_ENABLE_OSMESA_CONTEXT OR
VTKm_ENABLE_EGL_CONTEXT
)
vtkm_find_gl(REQUIRED GL GLEW
OPTIONAL
QUIET)
endif()
#-----------------------------------------------------------------------------
if(TARGET vtkm_rendering_gl_context)
return()
endif()
add_library(vtkm_rendering_gl_context INTERFACE)
#-----------------------------------------------------------------------------
if(VTKm_ENABLE_GL_CONTEXT)
if(TARGET OpenGL::GLX)
target_link_libraries(vtkm_rendering_gl_context
INTERFACE OpenGL::OpenGL OpenGL::GLX GLEW::GLEW)
elseif(TARGET OpenGL::GL)
target_link_libraries(vtkm_rendering_gl_context
INTERFACE OpenGL::GL OpenGL::GLU GLEW::GLEW)
endif()
elseif(VTKm_ENABLE_OSMESA_CONTEXT)
target_link_libraries(vtkm_rendering_gl_context
INTERFACE OpenGL::GL OpenGL::GLU GLEW::GLEW)
elseif(VTKm_ENABLE_EGL_CONTEXT)
target_link_libraries(vtkm_rendering_gl_context
INTERFACE OpenGL::OpenGL OpenGL::EGL GLEW::GLEW)
endif()