Adding Noise to Terrain
To create terrain with added noise, perform the following tasks:
- Select Activate terrain editing
(
) to enable terrain editing within the Design
View.
- Within the Terrain Editor window, click Noise.
- Optionally, specify a custom brush radius, a brush softness, a
number of features, the feature scale, a number of octaves for the
features, and the persistence of the features:
- Brush radius: In the Brush
Radius field, specify a number between 1 and 2147483647
(231 - 1). The default
value is 16.
A small number defines a small radius for the brush cursor with
which you define noisy terrain, and a larger number defines a
larger radius. A small radius allows you to design fine detail,
whereas a large radius allows you design large areas quickly.
- Brush softness: In the Brush
Softness field, specify a number between 0 and 1. The default
value is 0.
A small number defines a harder brush, which produces harsher lines
for the noisy terrain, whereas a larger number defines a softer
brush, which produces more rounded contours for the noisy terrain.
- Features: In the Features
field, specify a number between 1 and 2147483647 (231
- 1). The default value is 4.
A small number defines a smaller number of noise features, which
produces a less noisy terrain, whereas a larger number defines
a larger number of noise features, which produces much noisier
(“bumpier”) terrain.
- Feature Scale: In the FeatureScale
field, specify a number between 1.401298E-45 (1.4 x 10-45)
and 3.4028E+038 (3.4 x 1038).
The default value is 1.5.
The feature scale defines the height of each noise feature defined
with each click. A small number defines shorter noise features,
whereas a larger number defines taller noise features.
- Octaves: In the Octaves
field, specify a number between 1 and 10. The default value is
5.
The octave number defines the number of iterations of the features.
A small number defines fewer iterations of the features, which
produces less pronounced noise features, whereas a larger number
defines more iterations of the features, which produces more pronounced
noise features.
- Persistence: In the Persistence
field, specify a number between 0.1 and 1. The default value is
0.5.
The persistence defines the shape of the noise features. A small
number defines smoother features, whereas a larger number defines
sharper (“spikier”) features.
- To create noisy terrain: Within the Design View, position the cursor
where you want noisy terrain and left-click. You can also left-click
and drag to define areas of noisy terrain.
The following figure shows some noisy terrain using the default settings.
