build errors on Raspberry Pi 64bit beta OS - for use with AppCSXCAD

Hello everyone, please go easy on me - I’m pretty new to building anything on Linux (mainly low level embedded stuff) and I don’t know what information is required to make a question post that people can engage with. I’ll do my best but I’m happy to provide specific details if you tell me what is needed.

Context - openEMS is an electromagnetic finite difference time domain solver. It uses VTK in it’s build processes, which I presume is mainly required for rendering the simulation 3D models in AppCSXCAD. The solver itself runs in Octave or Matlab and is not dependent on generating a visualiser, although it does use CSXCAD to generate the mesh model, even if a render is not requested/displayed.

Last year I was able to comment out enough of the source files and replace other lines in the openEMS engine files that I could compile it on a Raspberry Pi 4 with Rasbian. This year, with the release of the Raspberry Pi OS 64bit beta, I have tried compiling again for the Raspberry Pi 4. Sadly I got nearly all the way through the build and the build failed due to some errors with VTK files that were expected but not found.

I realise that VTK is several versions ahead of those that are apparently available or that openEMS was developed for (vtk5 is what’s in the build instructions, so we’re going back a while) and please bear in mind that I am not aware of anyone else building openEMS on Arm - everything else was done on x86. Nevertheless, if anyone can help me understand these errors at the bottom of my log files, and perhaps help me avoid them, I’d be very grateful.

I used VTK7 and then when that didn’t work, I rolled back to VTK6.3 (which caused fewer errors). When I have enough user privileges to attach the log files in full, I will. But for now, here are the key messages. I have personally checked the folders they reference and the VTKTargets.conf file and the files are requested (maybe they are not needed and I could configure the build to ignore them?) and they are not where the error message says they looked for them.

-- The imported target "vtkRenderingPythonTkWidgets" references the file
   "/usr/lib/aarch64-linux-gnu/libvtkRenderingPythonTkWidgets.so"
but this file does not exist.  Possible reasons include:
* The file was deleted, renamed, or moved to another location.
* An install or uninstall procedure did not complete successfully.
* The installation package was faulty and contained
   "/usr/lib/cmake/vtk-6.3/VTKTargets.cmake"
but not all the files it references.

-- The imported target "vtk" references the file
   "/usr/bin/vtk"
but this file does not exist.  Possible reasons include:
* The file was deleted, renamed, or moved to another location.
* An install or uninstall procedure did not complete successfully.
* The installation package was faulty and contained
   "/usr/lib/cmake/vtk-6.3/VTKTargets.cmake"
but not all the files it references.

-- Found package VTK. Using version 6.3.0
-- vtk libraries vtkIOXMLvtkIOGeometryvtkCommonDataModelvtkCommonMathvtkCommonCorevtksysvtkCommonMiscvtkCommonSystemvtkCommonTransformsvtkIOCorevtkCommonExecutionModel/usr/lib/aarch64-linux-gnu/libz.sovtkIOXMLParser/usr/lib/aarch64-linux-gnu/libexpat.sovtkIOLegacyvtkIOPLY

Thanks in advance

VTK 6.3 is no longer supported. But it seems that the CMake package was installed, but the associated library files are not. Did you install VTK fully?