With the “rootlogon.C” file (in your current working directory) given below, one should be able to run all “VTK-9.0.x/Examples/Tutorial/Step*/Cxx/Cone*.cxx” in ROOT 6, e.g., as “interpreted” C++ macros:
root -q -e ".L Cone.cxx" -e "main();"
or:
[...]$ root
root [0] .L Cone.cxx
root [1] main();
root [2] .q
{ // rootlogon.C ...
{ // VTK-9.0.x ...
// it is assumed that the VTK-9.0.x has been built using something like this:
// mkdir /path/to/build/dir/VTK-9.0.x; cd /path/to/build/dir/VTK-9.0.x
// cmake -DCMAKE_INSTALL_PREFIX=${HOME}/work/VTK/VTK-9.0 /path/to/source/dir/VTK-9.0.x
// make install # build and then install everything in "CMAKE_INSTALL_PREFIX"
// patchelf --set-rpath "\$ORIGIN" ${HOME}/work/VTK/VTK-9.0/lib*/libvtk*.so # set "RUNPATH"
TString prefix = "${HOME}/work/VTK/VTK-9.0"; // same as "CMAKE_INSTALL_PREFIX"
TString lib = "lib"; // "lib" or "lib64" (usually depends on the architecture)
TString version = "-9.0"; // e.g., "" or "-9.0" (note: it's without the "patch version" here)
if (!prefix.EndsWith("/")) prefix += "/";
gSystem->SetDynamicPath(gSystem->ExpandPathName(prefix + lib + ":") + TString(gSystem->GetDynamicPath()));
gInterpreter->AddIncludePath(gSystem->ExpandPathName(prefix + "include/vtk" + version));
#if 0 /* 0 or 1 */
// these environment variables may be needed if one plans to execute shell commands from inside of a ROOT session
gSystem->Setenv("LD_LIBRARY_PATH", gSystem->ExpandPathName(prefix + lib + ":") + TString(gSystem->Getenv("LD_LIBRARY_PATH")));
gSystem->Setenv("PATH", gSystem->ExpandPathName(prefix + "bin:") + TString(gSystem->Getenv("PATH")));
TString python = "python2.7"; // e.g., "python2.7" or "python3.8"
// TPRegexp(".*PYTHON_VERSION_MAJOR=([0-9]*).+PYTHON_VERSION_MINOR=([0-9]*).*").Substitute(python = gROOT->GetConfigOptions(), "python$1.$2");
gSystem->Setenv("PYTHONPATH", gSystem->ExpandPathName(prefix + lib + "/" + python + "/site-packages:") + TString(gSystem->Getenv("PYTHONPATH")));
#endif /* 0 or 1 */
// these VTK components are needed to run all "VTK-9.0.x/Examples/Tutorial/Step*/Cxx/Cone*.cxx"
std::vector<TString> components
{ "CommonCore",
"FiltersSources",
"InteractionStyle",
"InteractionWidgets", // needed by "Step6/Cxx/Cone6.cxx" only
"RenderingOpenGL2" };
// load the corresponding shared libraries
for (unsigned long i = 0; i < components.size(); i++) {
TString l = gSystem->ExpandPathName("libvtk" + components[i] + version);
int v = gSystem->Load(l);
if (v < 0) std::cout << "Warning: cannot load " << l << " : " << v << std::endl;
}
// initialize VTK components (i.e., these which need it)
if (!(gInterpreter->IsLoaded("vtkAutoInit.h")))
gInterpreter->ProcessLine("#include \"vtkAutoInit.h\"");
for (unsigned long i = 0; i < components.size(); i++) {
TString m = "vtk" + components[i];
gInterpreter->Declare("VTK_AUTOINIT_DECLARE(" + m + ");");
if (gSystem->DynFindSymbol(nullptr, gInterpreter->GetMangledName(0, m + "_AutoInit_Construct", "")))
gInterpreter->Declare("VTK_MODULE_INIT(" + m + ");");
}
} // ... VTK-9.0.x
} // ... rootlogon.C
BTW. There exists also an “accompanying” discussion on the VTK forum: “Using VTK shared libraries in (CERN) ROOT”