Current situation:
The code that updates the status bar (QmitkImageNavigatorView::UpdateStatusBar()) currently assumes that the time steps (not time points) are always covered in terms of accessible data volumes for the top most visible node.
This is often not the case in heterogeneous scenes where we have different images and time geometries.
Before we fix that code in UpdateStatusBar() (and maybe other locations as well) we should discuss/clarify several questions:
# How to handle situations, when the top most image is not within the time bounds? Show N/A? Show the last timestep? Go to the "next" images (see 2)
# How is it handled for the rendering? Statusbar and renering should handle it the same way?
# How to handle situations, when the top most image does not cover the world coordinate?
# Currently the next valid top most node is selected. This is the analogy in the time domain to taking the top most node that covers the time bounds. Which in turn would men that nodes should disappear in the rendering, when the current time step is out of there time bounds.
# I think the logic for the time domain and the spatial domains should be the same.
Another more "fundamentel" questions that pops into my mind, when thinking about that matter is, but for visibility reasons I will spawn a sub task for that.