Seed The starting point for generating the terrain. The same seed will always generate the same terrain.
New Seed on Run: Randomly generate a new seed every time you generate terrain.
Size Factor: Width and Height will be powers of two based on this. Use your mouse wheel to adjust.
Altitude Adjustments: Raise or lower a generated map.
Tip: The same seed will generate the same terrain on the same proportions. As long as the ratio of length and width are the same (and the seed), increasing the dimensions will create a more detailed map although the basic structure will not change.