Depth (Layer) [Optional]
Depth of perspective (3d) view, to enable 3d view of a child layers in the panel layer, this option should be specified.
For example, 0.25 means 25% of layer size. Given a layer with size 400px x 200px, the perspective is (400 + 200) / 2 * 0.25 = 75px.
This option affects appearance of layer applied with 'Rotate X' or 'Rotate Y' or 'Translate Z' effect.