Gain Scalar

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Gain Scalar



Overview[edit]

The Gain scalar node creates a curve, the shape of which depends on the Gain value. The output of the node is the value of the gain curve corresponding to the Input value. Here's a graph showing the gain curve at two different Gain values:

Gain.gif

The output value will be between 0 and 1. The node expects both the Input and Gain values to be between 0 and 1. It does clamp these values to make sure that they are within that range.

Settings:

  • Name: This setting allows you to apply a descriptive name to the node, which can be helpful when using multiple Bias scalar nodes in a project.
  • Enable: When checked, the node is active, and when unchecked the node is ignored.
  • Gain: The value defining the shape of the gain curve, as in the graph above.


Error conditions:

  • It is an error for there to be no Input value. In that case 0 is output from the node.
  • It is an error for there to be no Gain value. In this case the Input value will be output.


Fun with Gain Scalar[edit]

The following examples show how the Bias scalar node can be used to modify the output of a node.


The image below shows the Bias scalar nodes effect on a radial gradient, as the Bias value changes from 0 to 1. GainScalar_01_RadialGradientGain.jpg

    Comparison of the effect of the Gain scaler node on a radial falloff, as its value changes from 0 to 1.


The images below illustrate the Bias scalar nodes effect on the three different Edge profiles, Smooth step, Bevel, and Radial, of the Simple shape shader.

    Comparison of the effect of the Gain scalar node on 3 profiles from the Simple shape shader node, as its value changes from 0 to 1.
    Node Network view showing Gain scalar modifying the output of the Simple shape shader before it gets displaced on the surface of the terrain.



A scalar is a single number. 1, 200.45, -45, -0.2 are all examples of scalar values.

A single object or device in the node network which generates or modifies data and may accept input data or create output data or both, depending on its function. Nodes usually have their own settings which control the data they create or how they modify data passing through them. Nodes are connected together in a network to perform work in a network-based user interface. In Terragen 2 nodes are connected together to describe a scene.

A shader is a program or set of instructions used in 3D computer graphics to determine the final surface properties of an object or image. This can include arbitrarily complex descriptions of light absorption and diffusion, texture mapping, reflection and refraction, shadowing, surface displacement and post-processing effects. In Terragen 2 shaders are used to construct and modify almost every element of a scene.