Add Colour

Add Colour

Overview

The Add family of nodes allow you to add the colour/scalar/vector coming into the Main Input by the color/scalar/vector coming into Input 2.

With Add Colour the addition is component-wise:

Main Input.red + Input 2.red
Main Input.green + Input 2.green
Main Input.blue + Input 2.blue

All nodes in this family have just one setting, which lets you assign a shader or function nodes to Input 2.

Settings:

• Name: This setting allows you to apply a descriptive name to the node, which can be helpful when using multiple Add Colour nodes in a project.

• Enable: When checked, the node is active and the Main Input value is added with the Input 2 value. When unchecked, only the Main Input value is passed through the node.

• Input 2: The values from the shader or function nodes assigned to this setting are added to the values of the Main Input.

Fun with Add Colour

Remember that each of the colour component values, the red, green, and blue channel values, from the Main Input and the Input 2 settings are added together to achieve the final result.

In this example, Main Input's colour values are red and the Input 2's colour values are green. When added together via the Add Colour node they make yellow.

In this example, a Power Fractal shader assigned to Input 2 provides green values and black values. When added together via the Add Colour node, the green values become shades of yellow while the black values let the red values from the Main Input pass through.

It’s possible for the component values to exceed the visual range of colours from pure black (0,0,0) to pure white (1,1,1), although this is not recommended, and in some shaders such as the Power Fractal v3 shader, parameters exist to clamp the colour component values at black or white.

In the example below, colours of the terrain appear unnaturally dark, almost burnt, when their colour component values are below 0,0,0. When component values exceed pure white, this can lead to clipping or unnatural shades of colour, such as the magenta areas in the image below.

When the evaluated component values (RGB) exceed the 0 to 1 range, the resulting colours can appear clipped or burnt in.

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

A vector is a set of three scalars, normally representing X, Y and Z coordinates. It also commonly represents rotation, where the values are pitch, heading and bank.

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.

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.