Add a periodic filter fonctionnality
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
A client requested to add a periodic filter fonctionnality.
The idea is to be able to create lightweight periodic meshes from existing grids. For each grid, a Multipiece data object is created. It contains the original grid plus periodic version of the grid at different periodic position (for now an angle value). The periodic meshes are very lightweight objects because we use mapped data arrays: data (point coordinates, vectors, tensors) are not copied but transformed on the fly when needed from the original arrays.