Add octree dependency to visualization

[frozar]

I tried to compilation test_visualisation with the following command line (enable only what is necessary for the test_visualisation target):

rm -rf ./* && cmake -DPCL_ONLY_CORE_POINT_TYPES=ON -DPCL_NO_PRECOMPILE=ON -DBUILD_tools=OFF -DBUILD_examples=OFF -DBUILD_apps=OFF -DBUILD_2d=OFF -DBUILD_features=OFF -DBUILD_filters=OFF -DBUILD_outofcore=OFF -DBUILD_people=OFF -DBUILD_recognition=OFF -DBUILD_registration=OFF -DBUILD_sample_consensus=OFF -DBUILD_ml=OFF -DBUILD_stereo=OFF -DBUILD_surface=OFF -DBUILD_geometry=ON -DBUILD_io=ON -DBUILD_kdtree=ON -DBUILD_octree=ON -DBUILD_search=ON -DBUILD_visualization=ON -DBUILD_global_tests=ON -DBUILD_tests_common=OFF -DBUILD_tests_geometry=OFF -DBUILD_tests_io=OFF -DBUILD_tests_kdtree=OFF -DBUILD_tests_octree=OFF -DBUILD_tests_search=OFF -DBUILD_tests_surface=OFF -DBUILD_tests_segmentation=OFF -DBUILD_tests_features=OFF -DBUILD_tests_filters=OFF -DBUILD_tests_keypoints=OFF -DBUILD_tests_people=OFF -DBUILD_tests_outofcore=OFF -DBUILD_tests_recognition=OFF -DBUILD_tests_registration=OFF -DBUILD_tests_segmentation=OFF -DBUILD_tests_sample_consensus=OFF -DBUILD_tests_visualization=ON -DGTEST_INCLUDE_DIR=/home/frozar/soft/googletest/googletest/include -DGTEST_SRC_DIR=/home/frozar/soft/googletest/googletest -DCMAKE_BUILD_TYPE=Debug .. && make -j8

I got the following compilation error:

Scanning dependencies of target test_visualization
[ 98%] Building CXX object test/visualization/CMakeFiles/test_visualization.dir/test_visualization.cpp.o
In file included from /home/frozar/wk/pcl_repo/search/include/pcl/search/pcl_search.h:45:0,
                 from /home/frozar/wk/pcl_repo/features/include/pcl/features/impl/feature.hpp:44,
                 from /home/frozar/wk/pcl_repo/features/include/pcl/features/feature.h:498,
                 from /home/frozar/wk/pcl_repo/features/include/pcl/features/normal_3d.h:44,
                 from /home/frozar/wk/pcl_repo/test/visualization/test_visualization.cpp:44:
/home/frozar/wk/pcl_repo/search/include/pcl/search/octree.h:43:38: fatal error: pcl/octree/octree_search.h: Aucun fichier ou dossier de ce type
compilation terminated.

This test of visualisation seems to depend on octree headers. So in this PR, I propose to update the CMakeLists.txt associated.

[SergioRAgostinho]

FYI: the tests for each module have their own individual dependencies (other than the module they test of course).

In this case visualization already depended on search which in turn depends on octree, so adding it was not a problem. If that was not the case, you would have added it to the optional dependencies of tests_visualization.

[taketwo]

If visualization depends on search which depends on octree, then why this dependency was not propagated to tests_visualization?

[SergioRAgostinho]

Because the use of target_link_libraries(foo PUBLIC deps) is inexistent. Check the current pcl_targets macros and you won't find it.

Our CMake system needs serious revamping.