A volume visualization driver in Geant4 for radiotherapy simulation

A volume visualization driver in Geant4 was developed in order to display a complex patient image and a calculated dose distribution in a radiotherapy simulation with an external volume visualizer. Monte Carlo simulation has been widely used for radiological simulation. In radiotherapy simulation, it applies to calculation of the dose distribution, optimization of the beam delivery system, and so on. Geant4 toolkit is utilized to build a simulator for that purpose. In that simulator, visualizer needs the volume rendering capability to display a complex volume data. However, there is no volume rendering capability in the visualization system in Geant4. The volume visualization driver extracts a patient data, calculated dose distributions, particle trajectories and geometrical information of beam delivery modules in the simulation, and then saves their information as a data file. With that data file, the external volume visualizer is able easily to display results of the simulation.