Redirect Shader

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Redirect Shader


Overview[edit]

The Redirect Shader "tricks" the shaders which are attached to it into thinking that the surface normal points along the positive X axis, positive Y axis or positive Z axis. Basically it modifies the shading state variable for the surface normal before calling the shaders, so that they think they are displacing a surface with a different normal. Any shader that displaces along the normal will then displace along these directions. Displacement in the negative X,Y,Z directions is accomplished if the displacement shader displaces negatively (e.g. if it indents a surface rather than raising it).

Settings:


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


  • Enable: When checked, the node is active and the settings below will affect the surface. When unchecked, the node is ignored.


  • X shader: The shader or function nodes assigned to this setting, will think that the surface normal points along the X axis.


  • Y shader: The shader or function nodes assigned to this setting, will think that the surface normal points along the Y axis.


  • Z shader: The shader or function nodes assigned to this setting, will think that the surface normal points along the Z axis.


Power fractal shader assigned to each of the X, Y, and Z axis.
Power fractal shader assigned to XYZ shader inputs.


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.

Literally, to change the position of something. In graphics terminology to displace a surface is to modify its geometric (3D) structure using reference data of some kind. For example, a grayscale image might be taken as input, with black areas indicating no displacement of the surface, and white indicating maximum displacement. In Terragen 2 displacement is used to create all terrain by taking heightfield or procedural data as input and using it to displace the normally flat sphere of the planet.

Literally, to change the position of something. In graphics terminology to displace a surface is to modify its geometric (3D) structure using reference data of some kind. For example, a grayscale image might be taken as input, with black areas indicating no displacement of the surface, and white indicating maximum displacement. In Terragen 2 displacement is used to create all terrain by taking heightfield or procedural data as input and using it to displace the normally flat sphere of the planet.

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.