Houdini 20.0 Nodes Geometry nodes

IsoSurface geometry node

Generates an isometric surface from an implicit function.

This node type is deprecated. It is scheduled to be deleted in an upcoming revision of Houdini.

Use Volume and Volume Wrangle instead

(Since version 19.5.)

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The IsoSurface operation uses implicit functions to generate isometric surfaces. It can be used to visualize grade 12 math homework in 3D. Alternatively, this operation can be used to visualize a 3D texture image.

The input to this node defines the bounding box within which the iso surface or volume primitive is created. Once the bounding box of the input is taken, the iso surface is clipped to its dimensions.



Implicit Function

Function for implicit surface building.

Minimum Bound

The minimum clipping plane boundary for display.

Maximum Bound

The maximum clipping plane boundary for display.

3D Texture

3D Texture File

The path to a 3D texture file

Reload 3D Texture

Reloads the texture file from disk

Use Texture Resolution for Divisions

A 3D texture file has an x, y and z resolution. Rather than manually specifying the sampling resolution for the iso surface, this uses the voxel boundaries in the .i3d file, which ensures that each voxel will be sampled one time.

Texture Channel

The channel of the 3D texture file which specifies the density field.

Density Threshold

Generate the surface where the texture file has this value.


The filter type to use when evaluating the 3d texture.

Filter Width

The filter width to use when evaluating the 3d texture, in voxels. The filter width is specified in units of the original texture file voxels, not output divisions.


The density of polygons along the xyz axes.

Build Volume

Instead of creating a polygonal isosurface, will create a volume primitive according to the expression.

Build Polygon Soup

Instead of creating separate polygon primitives, will create a polygon soup primitive.


X, Y, Z

Variables in the implicit function equation.


If the input geometry contains volume primitives, this is the total value of those volume primitives at the current point.

The value of each volume primitive is added to a running total to get the final $V value.

See also

Geometry nodes