Grass Clump - Surface Shaders Tab

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Grass Clump - Surface Shaders Tab

Description:
This tab has settings which allow you control the surface texture for the Grass clump.


Settings:

  • Surface shader: This parameter lets you assign a shader for the Grass clump surface.
  • Displacement tolerance: You might find surfaces with rough or spikey displacement occasionally show problems, such as being cut off at bucket edges or causing gaps in ray traced shadows. The Displacement tolerance parameter can help to improve this. Changing this parameter can greatly increase render times so you should only change it if you have a specific need. The default value is 1. If you're having problems try increasing it to 2. If that improves things but doesn't completely resolve them then try increasing it by small increments. You would not generally want to go above a value of 4 or 5 however.


Back to: Grass Clump

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 parameter is an individual setting in a node parameter view which controls some aspect of the node.

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.

When Terragen renders, it divides the image up into buckets or tiles. Each bucket is rendered separately, allowing multiple buckets to be rendered at once. It also allows memory to be used more efficiently.