In TS Volume view chunk spatial data

For moderately large spaces (427 x 547 x 339) the viewer is unusable.
It loads the whole space at a time point. The server struggles to jsonify the 300MB array using gigabytes of memory.

A solution would be to always ask for slices and assemble them in the client.
Or / And subsample the volume.
It would also help if we could avoid marshalling doubles to json.