Feature request: GROMACS force field parsing

[SSchott]

As discussed in FL:
Being able to parse force field files from GROMACS (and from CHARMM too for that matter), that include atom names with 4 letter codes and LJ cross-terms, and write topologies in AMBER format. The latter should be achievable similarly as with LJEDIT format from David Cerutti.

[drmeister]

Ok, sounds good. I'm just adding Smirnoff - and that is leading me to generalize some of the force field code that will make it easier to handle other force field files.
I'll be back once I have the changes in place.

[drmeister]

To be specific for GROMACS what force field files are you looking for?
Which of these files do you want cleap to read and write?
http://manual.gromacs.org/documentation/2018/user-guide/file-formats.html#mdp

[SSchott]

I guess itp and top would be required. You can use the martini force field as a test case: http://cgmartini.nl/index.php/force-field-parameters/particle-definitions
They have a v3.0b that you could try.

[drmeister]

The martini force field is a course-grained model - is that what you are using?
I thought you were using the GROMOS force field.

[SSchott]

I am interested in martini right now, but the parsing should work irrespective of being GROMOS or martini, right?