Floor+Wall
This command creates a new UCS at the intersection of the two extracted planes: one on the floor and the other on the wall.
No selection is required to launch the command.
Launch the command.
Click the first point on the floor using Define points. A local plane is extracted on the floor.
To delete this point, click Backspace or Delete.
In the same way, click the second point on a wall. A second plane is extracted on the wall.
The Z-axis of the created UCS corresponds to the WCS Z-axis.
The X-axis will now be aligned at the intersection between the floor and wall planes.