Houdini 20.5 Nodes VOP nodes

Environment Map VOP node

Sets the environment map (on an infinite sphere) and returns its color.

This operator sets the environment map (on an infinite sphere) and returns its color. If the image does not have an alpha channel associated with it (e.g. a JPEG image) and the operator returns RGBA, the alpha component will be set to 1.

See how to create an environment/reflection map.

Parameters

Signature

RGB or RGBA values.

Environment Map

Image file to use as environment map.

Wrap

Determines how the image is evaluated when the texture coordinates are outside the range 0 to 1. The options are:

Repeat

(string value repeat). The image map repeats outside the range 0 the range 0 to 1. Basically, the integer component of the texture coordinate is ignored.

Streak

(string value streak). Texture coordinates are clamped to the 0 to 1 range.

Decal

(string value decal). Coordinates outside the range 0 to 1 will evaluate to the border color rather than an image color.

Filter Type

type of anti-aliasing filter to be used for evaluation. The options are:

Box

(string value box)

Gaussian

(string value gauss)

Bartlett/Triangular

(string value bartlett)

Sinc Sharpening

(string value sinc)

Hanning

(string value hanning)

Blackman

(string value blackman)

Catmull-Rom

(string value catrom)

Mitchell

(string value mitchell)

Point Sampling

(string value point)

Filter Width

Blurs the environment map based on derivatives in shading contexts. For contexts that do not provide derivatives, such as the sop context, this parameter will have no effect and you should instead use Texture Blur or Pixel Blur. In shading contexts, filtering will be proportional to the micropolygon size, with a filter width of 1 filtering one micropolygon.

Filter Angle

Half angle in degrees over which the environment map should be blurred.

Border Color

Border color when Decal wrapping is used.

Extrapolate Derivatives

Specifies whether derivative extrapolation should be used when computing anti-aliasing information.

Interpolate MIP Levels

Specifies whether RAT files should interpolate between different MIP levels. If enabled, it will help remove discontinuities when different MIP levels of a RAT file are accessed. However, the results of texture evaluation will be slightly softer (i.e. blurrier) and will take twice as long to compute.

See also

VOP nodes