Issue
I’m running cmake version 3.23.0-rc1, on ubuntu 20.04. I built vtk-8.2 from source; cmake, make, then ‘make install’. Now I am trying to find the VTK package for my own application, using cmake’s find_package(VTK). The application’s CMakeLists.txt contains this:
find_package(VTK)
message("VTK_FOUND: ${VTK_FOUND}")
message("VTK_INCLUDE_DIRS: ${VTK_INCLUDE_DIRS}")
message("VTK_LIBRARIES: ${VTK_LIBRARIES}")
Result is that VTK_FOUND=1, VTK_LIBRARIES contains many entries, but VTK_INCLUDE_DIRS is blank/empty. Why would this be? I do see file /usr/local/lib/cmake/vtk-8.2, which contains many *.cmake files. But I don’t see a corresponding /usr/local/include/cmake directory, despite the presence of /usr/local/include/vtk-8.2. Is that expected? Here is the output:
VTK_FOUND: 1
VTK_INCLUDE_DIRS:
VTK_LIBRARIES: VTK::WrappingTools;VTK::ViewsQt;VTK::ViewsInfovis;VTK::CommonColor;VTK::ViewsContext2D;VTK::loguru;VTK::TestingRendering;VTK::TestingCore;VTK::vtksys;VTK::RenderingQt;VTK::PythonContext2D;VTK::RenderingVolumeOpenGL2;VTK::RenderingOpenGL2;VTK::glew;VTK::opengl;VTK::PythonInterpreter;VTK::Python;VTK::RenderingLabel;VTK::octree;VTK::RenderingLOD;VTK::RenderingImage;VTK::RenderingContextOpenGL2;VTK::IOVeraOut;VTK::hdf5;VTK::IOTecplotTable;VTK::IOSegY;VTK::IOParallelXML;VTK::IOPLY;VTK::IOOggTheora;VTK::theora;VTK::ogg;VTK::IONetCDF;VTK::netcdf;VTK::IOMotionFX;VTK::pegtl;VTK::IOParallel;VTK::jsoncpp;VTK::IOMINC;VTK::IOLSDyna;VTK::IOInfovis;VTK::libxml2;VTK::zlib;VTK::IOImport;VTK::IOGeometry;VTK::IOVideo;VTK::IOMovie;VTK::IOExportPDF;VTK::libharu;VTK::IOExportGL2PS;VTK::RenderingGL2PSOpenGL2;VTK::gl2ps;VTK::png;VTK::IOExport;VTK::RenderingVtkJS;VTK::RenderingSceneGraph;VTK::IOExodus;VTK::exodusII;VTK::IOEnSight;VTK::IOCityGML;VTK::pugixml;VTK::IOAsynchronous;VTK::IOAMR;VTK::InteractionImage;VTK::ImagingStencil;VTK::ImagingStatistics;VTK::ImagingMorphological;VTK::ImagingMath;VTK::GUISupportQtSQL;VTK::IOSQL;VTK::sqlite;VTK::GUISupportQt;VTK::GeovisCore;VTK::libproj;VTK::InfovisLayout;VTK::ViewsCore;VTK::InteractionWidgets;VTK::RenderingVolume;VTK::RenderingAnnotation;VTK::ImagingHybrid;VTK::ImagingColor;VTK::InteractionStyle;VTK::FiltersTopology;VTK::FiltersSelection;VTK::FiltersSMP;VTK::FiltersPython;VTK::FiltersProgrammable;VTK::FiltersPoints;VTK::FiltersVerdict;VTK::verdict;VTK::FiltersParallelImaging;VTK::FiltersImaging;VTK::ImagingGeneral;VTK::FiltersHyperTree;VTK::FiltersGeneric;VTK::FiltersFlowPaths;VTK::FiltersAMR;VTK::FiltersParallel;VTK::FiltersTexture;VTK::FiltersModeling;VTK::FiltersHybrid;VTK::RenderingUI;VTK::DomainsChemistry;VTK::CommonPython;VTK::WrappingPythonCore;VTK::ChartsCore;VTK::InfovisCore;VTK::FiltersExtraction;VTK::ParallelDIY;VTK::diy2;VTK::IOXML;VTK::IOXMLParser;VTK::expat;VTK::ParallelCore;VTK::IOLegacy;VTK::IOCore;VTK::doubleconversion;VTK::lz4;VTK::lzma;VTK::utf8;VTK::FiltersStatistics;VTK::eigen;VTK::ImagingFourier;VTK::ImagingSources;VTK::IOImage;VTK::DICOMParser;VTK::jpeg;VTK::metaio;VTK::tiff;VTK::RenderingContext2D;VTK::RenderingFreeType;VTK::freetype;VTK::kwiml;VTK::RenderingCore;VTK::FiltersSources;VTK::ImagingCore;VTK::FiltersGeometry;VTK::FiltersGeneral;VTK::CommonComputationalGeometry;VTK::FiltersCore;VTK::CommonExecutionModel;VTK::CommonDataModel;VTK::CommonSystem;VTK::CommonMisc;VTK::CommonTransforms;VTK::CommonMath;VTK::CommonCore
Solution
find_package(VTK) no longer sets VTK_INCLUDE_DIRS variable. If you look into description part of vtk-config.cmake (script CMake/vtk-config.cmake.in contains template of that file), then you find no note about VTK_INCLUDE_DIRS.
Since VTK_LIBRARIES variable contains IMPORTED targets (in form of VTK::foo), linking with the content of that variable using target_link_libraries will automatically provide include directories.
Answered By - Tsyvarev Answer Checked By - Mildred Charles (WPSolving Admin)