Loads a texture map into an attribute.
The Input Surface points or primitives will be given the loaded values.
The texture will be read from the Load File,
which may contain '<UDIM>' (without the single quotes),
to be replaced with standare UDIM file specification,
based on the texture coordinates that are encountered.
The texture maps are sampled into a named Attribute which has a
Class of Point or Primitive
and a Type of Real, Integer, Vector, or String.
The Map To Min and Max can be used to scale the results,
and Random can be used to add noise.
tested in Houdini
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