[Paraview-developers] Moving to hdf5-1.8.x

[Biddiscombe, John A.]

> I am confused about why take out HDF5 now that it is converted to CMake.
> That should make it easer to cram it into ParaView.

hdf being properly cmakeified makes it harder than it used to be, previously we just bodged it and it was ok, but now
1) vtkhdf5 instead of hdf5 - have to override hdf5_EXPORTS otherwise dll's don't work, also have to make sure that projects using pv as a library get the right names, it was a hack in the current version.
2) findZlib inside hdf5 won't pick up vtkzlib unless we force things - I don't want to wrap every single hdf5 option inside an IF overridden by parent project ....clause
3) make install needs to be overridden inside hdf5 to pick up the targets and install them alongside pv - and get the names right
4) every time I get it working, someone else breaks it and I'm tired of redoing it again and again.
5) Override options for parallel, fortran, tools, other libs, do we let the user have complete freedom to configure all these or not. All extra work now that hdf5 proper has dozens of possibilities.
6) I'd like to findhdf5 cleanly but we have internal build, external build, old non cmakeified 1.8, older 1.6, other flavours. got to get all consistent.

I'm fed up with it and want to do something else. A simple external hdf configured and built independently makes life easier.

I thought that the cmake externalproject_add() was going to save me, but it turns to not work the way I thought.

There really needs to be a proper external project method whereby a sub project can be build and integrated cleanly using a simple findXXX.

JB