=== Drawing Planar Objects on Horizontal Work Planes ===
[[Image:PMOM23B.png|thumb|280px|EM.Picasso's Navigation Tree populated with planar objects.]]
As soon as you start drawing geometrical objects in the project workspace, the '''Physical Structure''' section of the navigation tree gets populated. The names of traces are added under their respective trace type category, and the names of objects appear under their respective trace group. At any time, one and only one trace is active in the project workspace. The name of the active trace in the navigation tree is always displayed in bold letters. An active trace is where all the new objects you draw belong to. By default, the last defined trace or embedded object set is active. You can immediately start drawing new objects on the active trace. You can also set any trace or object set group active at any time by right-clicking on its name on the navigation tree and selecting '''Activate''' from the contextual menu.
[[Image:Info_icon.png|40px30px]] Click here to learn more about '''[[Building Geometrical Constructions in CubeCAD#Transferring Objects Among Different Groups or Modules | Moving Objects among Different Groups]]'''. <table><tr><td> [[Image:PMOM23B.png|thumb|280px|EM.Picasso's Navigation Tree populated with planar objects.]] </td></tr></table>
[[EM.Picasso]] has a special feature that makes construction of planar structures very convenient and straightforward. <u>The horizontal Z-plane of the active trace or object set group is always set as the active work plane of the project workspace.</u> That means all new objects are drawn at the Z-coordinate of the currently active trace. As you change the active trace group or add a new one, the active work plane changes accordingly.