OpenGL

OpenGL is the probably the only visualization driver that can be used to animate particles’ motion through their global time.

// only "rich" trajectories contain time information
/vis/scene/add/trajectories rich
// time interval needs to be set with one of the trajectory models
/vis/modeling/trajectories/create/drawByParticleID
/vis/modeling/trajectories/drawByParticleID-0/default/setTimeSliceInterval 0.01 ns
// let the particle go
/run/beamOn
// set start time and a time window after the start time
/vis/viewer/set/timeWindow/startTime 0 ns 0.05 ns
// save the view to a file, g4_00.g4view
/vis/viewer/save
// save next view to a file, g4_01.g4view
/vis/viewer/set/timeWindow/startTime 1 ns 0.05 ns
/vis/viewer/save
// ...
// change all views together and create a lot of G4OpenGL_viewer-0_????.jpg
/vis/viewer/interpolate ! ! ! ! export

One can create animation using the jpg files exported from Geant4:

ffmpeg -i "G4OpenGL_viewer-0_%4d.jpg" -y animation.gif