Mode: Edit mode
Panel: Mesh tools panel (Editing context, F9)
Noise is quite an old feature. The recent Blender versions have a much more flexible tool to realize these sort of effects: the Displace modifier. You are strongly encouraged to use it rather than the Noise tool – some of the key advantages of the modifier are that he can be canceled at any moment, you can precisely control how much and in which direction the displacement is applied, and much more…
The Noise function allows you to displace vertices in a mesh based on the grey-values of a texture applied to it. So, you must have a texture assigned to the material, even if that texture is not Mapped To anything. In your texture, you should enable No RGB to convert colour textures to a gradient. You should also have subdivided your object enough to have many vertices to act on.
Use Noise to generate great landscapes or make mesh surfaces more real-world (pitted, un-smooth). The Noise function displaces vertices along the object’s ±Z-Axis only. To deform your mesh’s other dimensions, simply rotate your object and apply rotation, or rotate the vertices in Edit mode, and apply Noise. Then, rotate it back again to get your original orientation.
Noise permanently modifies your mesh according to the material texture. Each click adds onto the current mesh. For a temporary effect, map the texture to Displacement for a render-time effect. In Object/Edit mode, your object will appear normal, but will render deformed.
Add a plane and subdivide it at least five times. To do that you can either use the Subdivide or Subdivide Multi entry in the Specials menu accessed via W; see (Subdivide tools in Specials menu). Using Subdivide Multi is faster and easier. Select Subdivide Multi and enter 5 for the Number of Cuts popup dialog.
Now add a material and assign a Clouds texture to it. Adjust the NoiseSize to 0.5. Choose white as the color for the material and black as the texture color, to give us good contrast for the noise operation.
Ensure that you are in Edit mode and that all vertices are selected, then switch to the Editing context (F9). Press the Noise button in the Mesh Tools panel (Noise button in Editing context) several times until the landscape looks nice. (Noise application process) is an example of applying the noise tool, showing the original – textured – plane as well as what happens as you press Noise. From top left to bottom right: plane with texture, sub-divided plane, Noise button hit 2, 4, 6 and 8 times.
Remove the texture from the landscape now because it will disturb the look. Then add some lights, some water, smooth the terrain, and so on (Noise generated landscape).
The noise displacement always occurs along the mesh’s z coordinate, which is along the direction of the z axis of the Object local reference.