Get function nodes retrieve specific pieces of information about the scene.
Get Altitude
Get Altitude in Texture
Get Camera Position
Get Diffuse Colour
Get Emitted Colour
Get Final Alpha
Get Final Colour
Get Final Opacity
Get Frame Number
Get Normal
Get Normal in Geometry
Get Normal in Texture
Get Position
Get Position in Geometry
Get Position in Texture
Get Ray Origin
Get Specular Colour