I.4. Drawing Area

The Drawing Area (located in the central and right side of the main window) is provided with a grid, where the nodes of the PN graph are to be placed, and with two scrollbars (on the right and bottom sides) for moving the desired parts of the graph into view.

The Drawing Area is an axes MATLAB object and it is organized as a matrix with 50 rows and 50 columns. The bottom left-hand corner corresponds to the (0,0) cell, whereas the upper right-hand corner to the (49,49) cell. In one cell the user can draw a single node (place or transition), so that the total number of places and transitions in a model cannot exceed 2500.

Using the Zoom In / Zoom Out commands from the View menu, the number of the cells is decreased/increased with 10 cells on each axis. The Show Grid command adds/removes the grid lines to/from the Drawing Area.