Houdini 19.0 Nodes VOP nodes

MtlX Image VOP node

Samples data from a single image, or from a layer within a multi-layer image.

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Samples data from a single image, or from a layer within a multi-layer image. When used in the context of rendering a geometry, the image is mapped onto the geometry based on geometry UV coordinates, with the lower-left corner of an image mapping to the (0,0) UV coordinate (or to the fractional (0,0) UV coordinate for tiled images).

Tips

  • When reading normal maps, set the type to “vector3”, to ensure colorspace is not applied to the incoming data.

Paramters

file

The URI of an image file. The filename can include one or more substitutions to change the file name (including frame number) that is accessed, as described in the Filename Substitutions section above.

layer

The name of the layer to extract from a multi-layer input file. If no value for layer is provided and the input file has multiple layers, then the 'default' layer will be used, or 'rgba' if there is no 'default' layer. Note: the number of channels defined by the type of the image must match the number of channels in the named layer.

default

A default value to use if the file reference can not be resolved (e.g. if a <geometry token>, [interface token] or {hostattr} is included in the filename but no substitution value or default is defined, or if the resolved file URI cannot be read), or if the specified layer does not exist in the file. The default value must be the same type as the image element itself. If default is not defined, the default color value will be 0.0 in all channels.

texcoord

The name of a vector2-type node specifying the 2D texture coordinate at which the image data is read. Default is to use the current u,v coordinate.

uaddressmode

Determines how U coordinates outside the 0-1 range are processed before sampling the image; see below. Default is 'periodic'.

vaddressmode

Determines how V coordinates outside the 0-1 range are processed before sampling the image; see below. Default is 'periodic'.

filtertype

The type of texture filtering to use; standard values include 'closest' (nearest-neighbor single-sample), 'linear', and 'cubic'. If not specified, an application may use its own default texture filtering method.

framerange

A string 'minframe-maxframe', e.g. '10-99', to specify the range of frames that the image file is allowed to have, usually the range of image files on disk. Default is unbounded

frameoffset

A number that is added to the current frame number to get the image file frame number. E.g. if frameoffset is 25, then processing frame 100 will result in reading frame 125 from the imagefile sequence. Default is no frame offset.

frameendaction

What to do when the resolved image frame number is outside the framerange range.

Outputs

out

float

VOP nodes