Hanyu Wei has done great job getting the basic drift and response simulation finished. In particular it now properly handles the exceeding fine-scale interpolation that is essential for having realistically smooth induction signals as a particle's ionization track moves from the region around one field response path to its neighbor. This improvement makes negligible impact on speed. Also included is proper drift processes and their statistics as well as the introduction of an addition RC response for amplifier after the preamp (for MicroBooNE).
Hanyu also added a new frame sink to write out "celltree" file format. This ROOT-based format has been used for a while now to transfer data between the Wire-Cell Prototype and other applications.