GGU-2D-SSFLOW: Preferences
After selecting this menu item you can enter various criteria for calculations in the following dialog box:

"Define starting points"
You can define the starting points of water particles."Starting point (circle)"
You can define several starting points, which can be grouped in a circle around the point you have determined. This can simplify the input of water particles, e.g., for wells within the system (key word: "50 day line")."Define end points"
If depressions (extraction wells) are present within a system, the result may, in certain circumstances, be an oscillation of the particle track around the well, as all velocities are directed towards the well. In this case, end points can be defined in order to avoid unnecessarily long computation times. A square area must be defined by the user around the end points. If a water particle enters this square, computation of the corresponding particle track is ended."Save points"
You can save starting points to a file, in order to have them available for a different system."Load points"
Starting points saved using the previous button can be reloaded into the program using this button.
After selecting one of the buttons for defining points, the following box opens:

The "In FEM mesh" check box displays the FEM mesh when specifying points; otherwise, only the system outline is displayed. Defined points will be locked on to the system nodes closest to the mouse pointer when clicked, if the "Lock-on to system nodes" check box is activated. Otherwise the points can be freely positioned within the system.
If some points are already defined, further points may be added by pressing the "Supplement existing points" button. Existing points are deleted if you exit the box via the "Define new points" button.