Advanced Perlin Noise is a second generation, highly customizable fractal terrain generator based upon the basic fractal noise techniques pioneered by Ken Perlin.
Perlin Noise works by layering the output of several sets of noise together. These layers are called octaves. The multiple octaves are combined together in a variety of ways to create the final result. Advanced Perlin Noise gives you total control over the types of noise used in each layer, as well as how they are combined. This allows you to create some very unique terrain shapes.

A Layout Generator interacts with the Layout View to provide a home for a set of shapes you can use to define terrain shapes, create masks, add roads, and more. When you double click on a Layout Generator, World Machine will automatically launch the Layout View for the appropriate layout. An entire section of the User's Guide is devoted to using Layout Generators and the Layout View; see Chapter 5 of the User's Guide.

The Tiled File Input device allows you to load a set of files that together represent a large expanse of terrain. From there, you can work with as large or small a portion of the tiled area as you want. In addition, since the Tiled File Input is simply another device in your world machine workflow, you can have as many input streams as you wish, allowing you to use many possibly overlapping tiled datasets, or to import texturing as well. The User's Guide has a section devoted to working with the Tiled File Input device; see Chapter 10 for more information. The focus here is explaining on what each checkbox or button does.

The Color Generator is the primary way to create colors in your Bitmap networks. It creates a single solid color that exists everywhere in the world; however by using the mask input or combining the output with color generators or other sources of texture, they form the basis of texturing networks.

The Mesh Output creates a triangulated mesh from the input heightfield. This is intended for general purpose rendering software or other applications that cannot use a Heightfield; The heightfield should be the preferred output method as it is a much more compact and efficient way of storing terrain data.

The Bitmap Output allows you to export a Bitmap datatype to a file. You may export to either 8 or 16bit per channel color formats.

The Convexity Selector discovers areas of the input terrain that are either highly exposed (convex) or recessed (concave). Convex areas are white (one), while concave areas are black (zero). Neutral areas that are neither will be neutral grey. This device can be very useful for texturing to either to help shadow recessed cracks in the terrain, or to bring out ridges and other areas that are highly exposed.

The Lightmap Generator produces a mask of light and shadow (called a Lightmap) that can be used in many applications to illuminate the terrain easily. The Lightmap Generator supports Raytraced lighting, and the output can be either exported to a file (by connecting a File Output node), or it can be used within World Machine to combine with a texturemap to produce a fully lit texture.

The normalmap generator encodes the terrain normal into an RGB texture; each direction component of the normal is mapped to a color. (R=X, G=Y, B=Z) is the default encoding. Among other uses, this information can be then used over a low-resolution mesh, giving much of the feel of a high resolution terrain with a fraction of the geometry data.

Map a color gradient to an input heightfield such that the values in the heightfield determine the color.

The Channel Splitter converts a Bitmap data packet into 3 individual component heightfields. You can use then use the individual channels in any manner you wish. You can split the bitmap into either Red/Green/Blue channels, or Hue/Saturation/Luminosity channels.

The Channel Combiner recombines three individual heightfields into a Bitmap packet. The opposite of the Channel Splitter, this device can treat the three heightfields as either Red/Green/Blue or Hue/Saturation/Luminosity values.

The Coastal Erosion device provides a quick approximation to the effect of large bodies of water on land; specifically, you can define a waterlevel and all adjacent heights will be adjusted so as to produce a beach and bluff region adjacent to the water. Note that the Coastal Erosion device does not perform any simulation to achieve its result, which has the benefit of making it very fast. However, the output is not as complicated as other simulation-based World Machine devices.

The Snow device simulates the accumulation of snow on the terrain. By varying the parameters, you can achieve results ranging from a slight dusting of snow to glacial accumulations. Note that unlike texture-based snow, the Snow device performs simulations and actually modifies the terrain heights, producing a very realistic snow effect.

Perlin Noise is a noise function developed by Ken Perlin.
By itself perlin noise produces output that looks something like lumps scattered about the world in random intensities. By layering multiple perlin noises at different frequencies and amplitudes, fractal noise functions that look to varying degrees like mountains can be created.
Perlin Noise serves as an extremely useful building block. It can be used as the basis for a terrain, to randomize the application of effect filters, and much more.

Voronoi noise implements a cellular texture basis function as described by Steven Worley. Voronoi noise has sharp discontinuities (ridges), and can form the basis for some very interesting terrain effects.

The Constant generator simply creates a level, flat terrain of a constant height.

The Gradient generator produces a constantly sloping plane that is optionally tiled or clipped in world space.

The Radial Gradient generator creates shapes that are all centered around one point in space.

The File Input imports a bitmap or terrain file from disk and inserts it into the world at a location and scale specified. The File Input device can read TER, BT, HFZ, PNG, TIFF, BMP, TGA, R32, R16, and RAW formats.

The File Output device saves the fully built heightfield to disk.
Only the heightfield information is saved -- any color-height mapping applied in World Machine is for illustration only, and is lost.

The Splitter device allows you to wire a single output to several different inputs. In other words, it “splits” the output wire into multiple paths. You can configure the number of output ports on the splitter.

The Combiner combines two seperate terrains into one. There are a variety of different methods that can be used to combine the terrains -- each will give a different effect.

The Chooser blends two heightmaps (Input Ports A and B) together based upon guidance from a 3rd input (Input C). Low or high values of input C will strongly favor one or the other of the inputs, while middle values will blend the two.

The Clamp device performs scaling and clipping on the terrain heights in the input heightfield. Scaling means to change the heights of a terrain uniformly. For example, scaling a terrain by 0.5 would reduce all height values by 50%. Clipping means to eliminate any values outside of a certain height range. Clipping a terrain to 0.5 would set any height values above 0.5 down to 0.5.

A set of simple operations that can be performed upon a heightfield.
The usefulness of this set of operations is mostly superseceded by newer and more powerful devices.

The Terrace device creates evenly spaced terraces (level areas) in the input terrain. This can be used to simulate exposed rock strata layers, a river eroding multiple bank levels, and much more.