The following should be added:

Global reinit:

1. The orientation of the worldgeometry, which basically defines the rendering space, is set to the standard coordinate system
2. The size of the worldgeometry is calculated, so that it includes all loaded data (depends on size and position of you loaded data)
3. The spacing is set to the smallest existing spacing regarding you loaded data

Reinit:

1. The orientation of the worldgeometry, is aligned according to the orientation of the currently selected datanode
2. The size of the worldgeometry is set to the size of the currently selected datanode
3. The spacing is set to the spacing of the currently selected datanode