It is possible to define the geometry of slabs as rectangular or user defined.
Rectangular
When defined, the following slab dimensions should be determined:
- Thickness.
- Length Lx.
- Width Ly.
User defined
When defined, specify the successive nodes of a slab.
- Graphically, indicating positions of points in the panel in the right-hand side of the dialog.
- Coordinates of nodes entered in the table.
Values in the table may be modified; a change of coordinates in the table results in a change of slab geometry in the drawing presented in the dialog.
The top right part of the dialog holds the following tools.
Toggles the ruler. 
Translates / changes the reference point (switching on / off). 
Defines the grid. Cells of the grid (in the direction X and Y) and a position in the coordinate system may be defined. 
Toggles a graphical definition of the slab contour.
For a slab of a user-defined shape, it is necessary to determine a slab thickness.