# Specifying Explicit Hierarchy Levels For One Layer Or A Layer Group

By default, only the hierarchy levels that are selected in the hierarchy level selection boxes are shown, i.e. if levels 0 to 1 are selected, just the top level shapes and instances are shown. This selection can be modified for certain layers or layer groups. To specify a different hierarchy selection for a certain layer, use an optional source specification element, the hierarchy level selector:

#[<lower-level>][ .. <upper-level>]

Upper and lower level can be omitted. In this case, the respective level is not overridden. The upper level can be '*' which means: every level that is available. If just one level and no ".." is given, it is taken as upper level and the lower level is set to zero.

Some examples might illustrate this:

#* | Display all hierarchy levels
#0..1 | Display top level only
#..5 | Override upper level with 5
#2.. | Override lower level with 2
#..* | Override upper level setting by "all levels"

Modifications of this notation are provide in order to support more use cases. Instead of specifying a single number for the level, the following alternative notations are supported:

(1) | Relative specification: Hierarchy level 1 related to the current cell's level. The effective specification differs in "Descend" mode where the current cell is on a lower hierarchy level than the context cell which is the top cell drawn.
<1 | Constrained specification: Hierarchy level 1 or less if the upper or lower default level set in the user interface is less.
>1 | Constrained specification: Hierarchy level 1 or greater if the upper or lower default level set in the user interface is greater.
(>1) | Combined specification: Hierarchy level 1 related to the current cell's level or less.
>* | Equals the currently set maximum hierarchy level.

For example:

#(0)..(1) | The top level of the current cell (works also in "Descend" mode).
#>0..<1 | Everything exactly on top level unless the top level is not selected in the controls.
#>1..<* | Everything below the context cell's top level unless not selected by the user interface controls.
#(>1)..<* | Same than before but related to the current cell, not the context cell.