The ‘Terrain’ properties dialog is opened by a double click on the terrain, when the layer for environment is active.
The terrain is always positioned about its origin. If required it can be repositioned by entering an offset in the x and y direction. If the terrain is 100 x 100 m, an offset of 50 m in the x and y direction would thus reposition the bottom left-hand corner in the direction of the origin.
Since the terrain is a 3D solid, as we have already mentioned, you can also specify a thickness. Alternatively, you can allow the terrain to be automatically adjusted if, for instance, a basement floor is created below the ground floor. In this case the terrain automatically assumes the thickness of the basement floor, and creates a opening in the ground to match the contour of the building, as can be seen in the following illustration.