Get Normal in Geometry

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Get Normal in Geometry[edit]

Get Normal in Geometry

Provides the "Normal in Geometry" of the current Render State. The Render State is affected by any shaders which were called before this function is called, among other things.

Normal in Geometry is the surface normal, in world space, of the original undisplaced point on the surface being rendered. When sampling an atmosphere shader, Normal in Geometry is usually set to the local "Up" vector with respect to the planet to which the atmosphere shader is attached.

The Input connection is not used by this node.

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 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 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.