Houdini 20.0 Nodes Geometry nodes

Extrude geometry node

Extrudes geometry along a normal.

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For extruding polygon faces, use Poly Extrude instead.

You can use this node for:

Extrude by default uses the normal of the surface to determine the direction of extrusion. In the case of planar or open polygons, the normal is difficult to determine, and may not always provide the result that you expect. Turn on the Primitive Normals display in the Viewport display options to see the normals.

You can also extrude along an arbitrary vector, or along the face normal. You can specify the number of divisions in the extrusion.


If you want to extrude a line, use the Poly Extrude SOP.

Mouse and Keys


Drag to move the selected extrusion to a new location.

Alt + LMB

Moves the extrusion in direction of the height vector.


Finish the extrusion.

Extrude Menu

Front Face Toggle F

Toggles the creation of the extrusion’s front face.

Back Face Toggle B

Toggles the creation of the extrusion’s back face or cap.

Side Mesh Toggle I

Toggles the creation of the extrusion’s side meshes.

Finish Extruding Enter

Completes the extrusion of the geometry.


  • This op can be used for generating two offsetting curves where the distance between the two curves remains constant. To do this, make sure that you set Side Mesh to No Output, the first thickness to zero and adjust the second to increase or decrease the distance of the offset.

  • If your geometry contains normals that are pointed in many directions (say after reading geometry from a File SOP, or if you have a lot of open or non-planar polygons), you can fix it so that they are suitable for extrusion.

    Do this by appending a Group SOP to the SOP that contains your geometry, enable Normal, and reduce the Spread Angle to something less than 180° degrees (e.g. 90). Then append a Primitive SOP, which should work on the group made in the Group SOP. In the Face/Hull page, set the Vertex menu to Reverse.

    Now the normals in your geometry will all be oriented in the roughly the same direction, and ready for extrusion. To narrow the tolerance, decrease the Spread Angle further.


If you press Alt and drag the primitive by its normal, each primitive in the selection will be extruded along its normal.


You can also extrude points and edges by enabling them in the selection mask before choosing this operator. Extruded points create open polygons. Extruded edges create meshes or closed polygons.


Source Group

The primitives to extrude.

X-Section Group

The primitives to use as the cross section.


Point Fusion

Consolidates points of polygons that would otherwise overlap.

All points

Guarantees no overlapping points.


Provides more uniform control with overlapping only in extreme cases.

Individual Faces

Implemented only for backward compatibility.

Front Face

Type of geometry to create for front face.

Back Face

Type of geometry to create for back face.

Side Mesh

Type of geometry to create for sides with polygonal cross-sections.

Initialize Extrusion

Attempts to fit the cross section to the source.

Thickness Offset

Controls the tangential offset of the cross section profile.

Thickness Scale

Controls the x scale of the cross section profile.

Depth Offset

Moves the entire extrusion forward or backward along the extrusion.

Depth Scale

Controls the y scale of the cross section profile.


Translates the cross section such that the vertex specified is at the cross section origin.

Cusp Sides

Whether sides are to be smooth-shaded or faceted.

Side Cusp Angle

Threshold angle for edge faceting.

Consolidate Faces

Consolidates the points of the face to the points of the sides.

Remove Shared Sides

Prevents the creation of duplicate sides.

Hole Polygons

If polygons overlap in a plane the inner polygons will be stamped out of the outer polygons in a fashion similar to the hole sop. This allows you to extrude letters like O properly.

The problem with Hole Polygons is that it may incorrectly merge polygons that just happen to overlap. If one had shards of glass flying through space, it may happen that two shards overlap on one frame and will be incorrectly holed. Not only does this cut out the shape of one piece of glass from the other (an undesired effect), but it also will change the primitive count. To avoid this problem, turn off Hole Polygons.


Create Output Groups

Generates 3 groups. One for front, back and sides.

Front Group

Name of the front group.

Back Group

Name of the back group.

Side Group

Name of the side group.


Source Input

Input the op containing the curves that you want to extrude. The input can be polygons, Bezier curves, NURBS curves, or any combination of the three types.

Cross-Section Input

The op on this input will be used to define a cross-section. If not specified, a straight line is used to extrude the object. This cross-section should be an open Bezier, NURBS, or polygon drawn in the XY Plane.


ExtrudeFont Example for Extrude geometry node

This is an example of the Extrude SOP. It illustrates how volume and geometry are created from flat primitives.

It also demonstrates how to separate parts of the geometry into groups, and how to apply different shaders to each group.

See also

Geometry nodes