Game Editor Manual Chapter 10
Pattern LayoutsWhen a pattern layout is selected for a newly created random tile in the game, the given pattern will stretch over newly generated neighboring tiles. To add a new pattern layout, click on the 'Add Pattern...' button in a region's property panel. It will bring up the pattern selection dialog:
A pattern can be picked by clicking on the image of the pattern. If there are too many patterns in the dialog, use the 'Filter' text control to restrict which patterns the dialog may show. To edit the patterns, open the 'Pattern Editor' dialog by clicking on the button right to the 'Filter' text control.