Gmex tracks visualisation

The visualisation of the tracks has been implemented in this branch.

This code is based on the hit display plugin. Internally it works in the same way and has a similar graphical interface. Also, it takes the hdf5 input file. The plugin for generating the hdf5 file can be found on the repository (Here is the attached hdf5 file, already generated with this plugin Tracks_data.h5)

If you will find this visualisation good, may I ask you, where I can upload the plugin for generating the hdf5 file?

Here is a picture of the drawing tracks.