Generating the heightfield

If you project contains a design map, the heightfield is generated when you select the 'Operations→Heightfield→Generate map' option. This option can also be used to re-calculate the heightfield after, say, a modification to the design map. This will, however, invalidate the normals, attributes map, water map, light map and texture. This option will only be greyed-out if you have closed the design map in a design-level project.

For a project without a design map (eg. fractal, perlin), the heightfield is generated after you click the 'OK' button in the relevant algorithm wizard.

To see a typical heightfield, go here.