layermask
The layermask is a subset of layers that are considered active. When links are displayed in noodle, only the links on layermask layers are shown. It doesn’t make sense to show all the layers of a noodle at once given that all doodles are actually layers.
/my/working/directory
...
layermask: a_layer another_layer **current** yet_another...
<noodle>
Many commands will make use of the layermask. Changing the layermask does not cause any changes to the multiplex graph. You can toggle whether or not a layer is included in the layermask with the layer command.
By default commands will take effect on the current layer if the command only expects a single layer. If the command is the sort to make use of multiple layers, all the layermask layers will be used.