Справка Houdini на русском Nodes VOP nodes

Gradient 3D VOP node

Returns the gradient of a single channel 3D texture image at a specified position within that image.

This operator returns the gradient of a single channel 3D texture image at a specified position within that image.

If the position is outside of the bounding box of the image, the value returned will be 0. If the channel specified contains more values than the return type (i.e. a vector channel when a float return type is desired), the gradient of the first component of the vector will be returned. If the channel specified contains fewer values than the return type, the missing components will be filled with the last valid channel.

Texture files will be searched for in the path specified by the HOUDINI_TEXTURE_PATH environment variable.

Parameters

Signature

Float, vector, or vector4 values.

3D Image

3D image file used for look-up.

Channel

Channel to be evaluated.

Position

3D location in the image where to evaluate.

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

Filter width in both u and v directions.

See also

VOP nodes