Houdini 18.0 Nodes Geometry nodes

Sweep 2.0 geometry node

Creates a surface by sweeping a cross section curve along a spine curve.

On this page

Overview

This node takes a cross-section curve from the second input, distributes copies of it along a spine curve from the first input, and creates a surface between the distributed cross-section curves. It is an extremely versatile workhorse for generating procedural geometry.

This node will accept polylines, NURBS curves, or Beziér curves. By default the type of input curves determine the type of surface (for example, polylines produce polygons, NURBS curves produce NURBS surfaces), however you can override the surface type using the Primitive type parameter on the Construction tab.

Instead of using modeled cross-sections connected to the second input, you can use automatic circle, square, or line cross-sections using the Surface Shape parameter.

This node can handle multiple spines, and/or multiple cross-sections.

  • If there are multiple curves in the first (spine) input, the cross-section(s) is/are swepat along each spine curve separately.

  • If there are multiple curves in the second (cross-section) input, the cross-sections are ditributed along the curve length according to the Cross section order parameter on the Construction tab.

This node can handle closed spines and/or closed cross-sections. (Closed means that the curve is a loop — the first and last point of the curve are the same.)

  • If both the spine and cross-section are open, the node creates an open surface.

  • If either the spine or cross-section are closed, the node creates a tube.

    When one curve is open and the other closed, creating a tube, you can automatically add end-cap geometry using the End cap type parameter on the Surface tab.

  • If both the spine and cross-section are closed, the node creates a torus.

Positioning the curves

  • Spine curves can be anywhere in space.

  • This node assumes all cross section curves are modeled at the origin in the XY plane, with +Y up direction.

    Do not model the cross-section curve on (or at the beginning of) the spine curve.

  • When the curve is flat (planar), the node assumes it should orient the up direction of the cross-sections perpendicular to the curve plane.

    After construction, you can adjust the orientation of the cross-section curve(s) relative to the spine using the Roll and Yaw parameters.

Tip

This is a technical node. It is very useful for procedurally building surfaces from cross-sections. It is not as suitable for "artistic" curve-up modeling, since this node bases cross-section orientation and positioning on parameters and/or attributes, rather than where/how you modeled the curves.

Tips

Inputs

First (Backbone curves)

Should contain one or more spine curves. If the input has multiple curves, the cross-section(s) is/are surfaced along each spine separately.

Second (Cross section(s))

Should contain one or more cross-section curves. If the input has multiple curves,

Connecting modeled cross-section curves to the second input is optional. Instead, you can use automatic circle, square, or line cross-sections using the Surface Shape parameter.

Parameters

Backbone Curve Group

If this is blank, the node uses all curves from the first input, or you can specify a group or set of curves using group syntax. You can also click the Reselect button next to this field to select the curves in the viewport.

Cross Section Group

If this is blank, the node uses all curves from the second input, or you can specify a group or set of curves using group syntax. You can also click the Reselect button next to this field to select the curves in the viewport.

Surface

Surface Shape

What to use as the cross-section shape. The default is to use curves connected to this node’s second input.

Second Input Cross Sections

Use the curve or curves from the second input (taking into account the Cross section group field) as the cross-section(s).

Round Tube

Use a circle as the cross-section, producing a round tube. Scale the tube with the Radius parameter and set the number of sides the circle has with the Columns parameter.

Square Tube

Use a square as the cross-section, producing a boxy tube. Scale the tube with the Width parameter and set the number of subdivisions along each side with the Columns parameter.

Ribbon

Use a line as the cross-section, producing a ribbon shape. Scale the ribbon with the Width parameter and set the number of subdivisions across the line with the Columns parameter.

Surface Type

The surface topology of the generated surface.

The Columns option is useful for creating many curves from each input curve.

Points

Don’t create any primitives, only points.

Rows

Create a curve for each cross section in the grid.

Columns

Create a curve for each vertex around the grid, spanning the full curve.

Rows and Columns

Create curves corresponding with both the Rows option and the Columns option.

Triangles

Create triangles splitting the grid quads in a single direction.

Quadrilaterals

Create the grid quads as is.

Alternating Triangles

Create triangles splitting the grid quads in alternating directions.

Reverse Triangles

Create triangles splitting the grid quads in a single direction opposite that of the Triangles option.

Scale Cross Sections

When Surface shape is "Second Input", this scales the size of all cross-sections.

Columns

When Surface shape is "Round tube", "Square tube", or "Ribbon", this controls the density of the cross-section shape. For round, this is the number of sides the circle has. For square, this is the number of subdivisions along each side. For ribbon, this is the number of subdivisions across.

Radius

When Surface shape is "Round tube", the radius of the tube.

Width

When Surface shape is "Square tube" or "Ribbon", the width of the tube/ribbon.

Reverse Cross Sections

Turn this on to reverse the normals of the generated surface.

When this is on, the node treats cross section primitives as if they were reversed, which reverses normals on the generated surface.

Stretch Around Turns

Stretch cross-sections in the direction of curvature around turns in the spine. (Default on.) This avoids the cross-section appearing squished in turns. This is usually what you want, unless you have set Surface type to "rows" or "columns".

Max Stretch

When Stretch Around Turns is on, the maximum amount that cross sections will be stretched. The default is 10 (maximum 10× stretch). This prevents the cross-section from scaling wildly if, for example, the spine curve doubles back on itself.

End Caps

End Cap Type

When the spine curve is open and the cross-section curves are closed, the generated surface is a tube. The node can automatically create end-caps on the open ends of the tube.

None

Do not generate end-caps.

Single Polygon

Cap the ends with a single N-gon.

Grid

Cap the ends with a surface, controlled by the parameters below.

Side Single Polygon

When the spine is closed but the cross-sections are open, the sides of the generated surface are open rather then the ends. This closes the sides with an N-gon.

Cap Divisions

When End Cap Type is Grid, the number of rows in the end-cap surfaces.

Triangular Poles

When End Cap Type is Grid and this is on, the poles of end caps are made with triangles. When this is off (the default), the poles are made with quads with duplicate vertices.

End Cap Scale

When End Cap Type is Grid, this is the amount each end-cap "bulges out" from each end of the tube. Set this to 0 for no bulge, or to a negative number for an inward bulge.

End Cap Roundness

When End Cap Type is Grid, and End cap scale is not 0, this controls the curvature of the bulge. 1 is convex circular, 0 is linear, and -1 is concave circular.

End Caps Group

When this is on, the output geometry includes a group by this name, containing all end-cap geometry. This lets you treat the end-caps separately if necessary in down-stream nodes.

Scale

Apply Scale Along Curve

Scales the generated surface across the length of the spine curve according to the Scale ramp parameter.

Scale Ramp

When Apply scale along curve is on, this ramp lets you interactively scale the surface inward and outward along the length of the spine curve.

Rotation

Rotate Order

The order in which to apply the Pitch (around X/out), Yaw (around Y/up), and Roll or Twist (around Z/tangent) options below, when more than one can apply.

Pitch and Yaw may be useful to effectively apply a pre-transform to the cross sections before using them if they are not in the XY plane in the cross section input, which is why they default to being applied before the Roll or Twist.

These rotations are effectively applied to the cross sections before the transforms from the backbone curves, having the net effect of them being rotations in the space of the backbone curve frames.

Apply Roll or Twist

Apply the Roll and Twist parameters below to the cross-section curves.

Roll

A rotation, in degrees, around the spine curve direction, applied equally to every cross-section. You can use this to correct the orientation of the cross-section in relation to the curve.

Full Twists

A convenience to add full twists (for each interval set in the Twist per parameter). This node multiplies this by 360 and adds it to the number in Partial twist.

Partial Twist

The number of degrees of twist to add (for each interval set in the Twist per parameter).

Twist Per

The interval along each of which the total twist specified by the Full twists and Partial twist parameters is applied to the surface.

See the descriptions and image below.

Per Edge

The twist applies along each edge (the distance from each point in the curve to the next point).

Per Unit Distance

The twist applies each "world unit" of distance along the curve.

Scale by Attribute

The twist value is multiplied at each vertex by the value in the attribute named in the Twist ramp attribute paramter (this can be a vertex, point, primitive, or detail attribute). This product is applied as a roll at each vertex, not as an accumulating twist.

Per Full Curve by Edges

Applies the twist value once across the entire curve, divided equally among each edge.

Per Full Curve by Distance

Applies the twist value once across the entire curve, with the amount proportional to the distance along the curve.

Twist Ramp Attribute

When Twist Per is "Scale By Attribute", this is the name of the vertex, point, primitive, or detail attribute to multiply by the total twist amount (full twists combined with partial twist). This product is applied as a roll at each vertex, not as an accumulating twist.

Apply Yaw

Apply the Yaw parameters below to the cross-section curves. Yaw is a rotation around the cross-section’s "up" vector, usually thought of as "turning left or right".

Yaw

A rotation, in degrees, around the cross-section’s "up" vector, applied equally to every cross-section. (This is usually thought of as "turning left or right".) You can use this to correct the orientation of the cross-section relative to the curve.

Incremental Yaw

A rotation, in degrees, around the cross-section’s "up" vector (usually thought as "turning left or right"), to apply along each interval set in the Yaw per parameter.

Yaw Per

The interval along each of which the total rotation specified by the Incremental Yaw parameter is applied to the surface.

Per Edge

The yaw applies along each edge (the distance from each point in the curve to the next point).

Per Unit Distance

The yaw applies each "world unit" of distance along the curve.

Scale by Attribute

The yaw value is multiplied at each vertex by the value in the attribute named in the Yaw ramp attribute paramter (this can be a vertex, point, primitive, or detail attribute). This product is applied as a yaw at each vertex, not as an accumulating yaw.

Per Full Curve by Edges

Applies the yaw value once across the entire curve, divided equally among each edge.

Per Full Curve by Distance

Applies the yaw value once across the entire curve, with the amount proportional to the distance along the curve.

Yaw Ramp Attribute

When Yaw Per is "Scale By Attribute", this is the name of the vertex, point, primitive, or detail attribute to multiply by Incremental Yaw. This product is applied as a yaw at each vertex, not as an accumulating yaw.

Apply Pitch

Apply the Pitch parameters below to the cross-section curves. Pitch is a rotation around the cross-section’s "out" vector, usually thought of as "tilting up or down".

Pitch

A rotation, in degrees, around the cross-section’s "out" vector, applied equally to every cross-section. (This is usually thought of as "tilting up or down".) You can use this to correct the orientation of the cross-section relative to the curve.

Incremental Pitch

A rotation, in degrees, around the cross-section’s "out" vector (usually thought as "tilting up or down"), to apply along each interval set in the Yaw per parameter.

Pitch Per

The interval along each of which the total rotation specified by the Incremental Pitch parameter is applied to the surface.

Per Edge

The pitch applies along each edge (the distance from each point in the curve to the next point).

Per Unit Distance

The pitch applies each "world unit" of distance along the curve.

Scale by Attribute

The pitch value is multiplied at each vertex by the value in the attribute named in the Yaw ramp attribute paramter (this can be a vertex, point, primitive, or detail attribute). This product is applied as a pitch at each vertex, not as an accumulating pitch.

Per Full Curve by Edges

Applies the pitch value once across the entire curve, divided equally among each edge.

Per Full Curve by Distance

Applies the pitch value once across the entire curve, with the amount proportional to the distance along the curve.

Pitch Ramp Attribute

When Pitch Per is Scale By Attribute, this is the name of the vertex, point, primitive, or detail attribute to multiply by Incremental Pitch. This product is applied as a pitch at each vertex, not as an accumulating pitch.

Construction

Cross Sections

Cross Section Order

How the node decides what cross section(s) to use a each point along the spine curve.

All Cross Sections at Each Curve Vertex

Within a single curve’s output grid, at every single vertex, all cross sections will be used.

This is useful for if the cross sections collectively form a unit that should appear at each vertex within each grid, for example, to create a bulge at each vertex.

Each Cross Section At All Curve Vertices

Every curve will be separately surfaced once for each cross section.

This is useful if the cross sections should effectively act like a single, disconnected cross section, for example, to create multiple tubes for each curve.

Cycle Through Cross Section Primitives per Vertex

Within each single curve’s output grid, the cross section selected for each vertex will cycle through the cross sections, starting from the first cross section.

This is useful if the cross sections form all cross sections to be used along the curves in order, for example, if the cross section input contains all cross sections for a corridor in order.

Cycle Through Cross Section Primitives per Primitive

For each curve’s output grid, a single cross section will be selected, selecting the next cross section for each next curve.

This is useful if each curve has a different cross section to be used for it.

Choose Cross Section Primitives by Attribute

For each vertex, select a cross section to use based on the attribute specified in the Cross Section Attribute parameter.

Cross Section Attribute

When Cross Section Order is "Choose Cross Section Primitives by Attribute", this is the name of the attribute to use for selecting cross sections.

This can be a point, vertex, primitive, or detail attribute on the spine curve, or a primitive attribute on the cross-sections.

  • If this is an integer attribute on the spine, it will select cross sections by primitive number.

  • If this is an integer or string attribute present on both inputs, it will select a cross section with a matching value.

Primitive Type

The type of primitive to output (when Surface Type is not "Points"). "Automatic" generates the same type of surface as the input curves (for example, polylines create a polygon surface, NURBS curves produce a NURBS surface).

Ensure Unique Seam Vertices

If Surface Type is "Rows", "Columns", or "Rows and Columns", and the spine curve or cross-section is closed, this adds an extra vertex (if needed) to each curve to ensure that there are separate vertices for parametric curve u or v coordinate values 0 and 1.

If any output primitives are polygon soups, NURBS surfaces, Bezier surfaces, or bilinear mesh primitives, this option similarly also adds any extra vertices that would be needed to ensure that all uv seams are paramerized correctly.

Swap Rows and Columns

Adjusts the order of the points and primitives in the generated surface(s) to be column-major, having all points/primitives of one column before those of the next column, instead of the default (row-major, having all point/primitives of one row before those of the next row). Changing this also reverses normals, so you may also want to turn on Reverse Cross Sections to keep the current normals.

Close Implicit Backbone Curve if No Curve Input

If the node finds no spine curve in the first input, the node sweeps the cross sections in the second input as if there is a single curve with one vertex per cross section and all positions at the origin. When this is on, the node makes that implicit curve closed, treating the cross sections as forming a loop, instead of a line.

Up Vectors

Target Up Vector

The initial orientation of the cross-section around the direction of the curve. You can use the roll, yaw, and pitch parameters on the Surface tab to further adjust the orientation of the cross-sections on top of this.

Curve Normal

Match the cross-section up-vector to the curve normal. This is useful when the curve is planar, it orients the cross-sections perpendicular to the plane.

X/Y/Z Axis

Match the cross-section up-vector to the X, Y, or Z axis.

Attribute

Get the up-vector from a per-curve value in a primitive attribute, or a shared value in a detail attribute. Set the attribute name in the Start up attribute parameter.

Custom

Match the cross-section up-vector to a custom vector. Set the custom vector in the Start up-vector parameter.

Target Up Vector at Start (else Average)

When this is on, at each point the node tries to get closest to the initial up-vector, while staying perpendicular to the spine curve tangent. When this is off, it tries to get closest to the average of all vertex up-vectors, instead of the initial up-vector.

Use Target End Up Vector

When Target up-vector at Start is on, and this is on, the node adjusts any twist along the spine to ensure the final up-vector is as close as possible to the target up-vector, without affecting the initial up-vector.

If Target up-vector is "Attribute" or "Custom", there are separate End Up Attribute and End Up Vector parameters, in order to specify different end up-vectors from the start up-vectors.

Start Up Attribute

When Target Up Vector is Attribute, this is the name of the primitive or detail attribute to use for each curve’s target up-vector.

End Up Attribute

When Target Up Vector is Attribute and Use Target End Up Vector is on, this is the name of the primitive or detail attribute that provides the target up-vectors at the end of the curve.

Start Up Vector

When Target up-vector is "Custom", this is the target up-vector at the end of the curve.

End up-vector

When Target up-vector is "Custom" and Use Target End Up Vector is on, this is the target up-vector at the end of the curve.

Tangents

Tangent Type

How to compute the spine curve’s tangent direction at each point. If Transform using curve point attributes is on and the spine curve has the required attributes, this is ignored.

(The Stretch Around Turns option always computes the stretch and stretch direction based on the "Average of Edge Directions" tangent, regardless of this setting.)

Average of Edge Directions

Average of the normalized directions of the previous and next edge.

Central Difference

Average of the non-normalized previous and next edge vectors.

This is similar to the "Central Difference" option for Velocity Approximation on the Trail node.

Previous Edge

Previous edge direction.

Next Edge

Next edge direction.

Z Axis (Ignore Curve)

The tangent will be chosen as the Z axis, regardless of the curve.

This can be useful if the cross sections have already been rotated to the desired orientation.

Make Closed Curve Orientations Continuous

Any extra rotation required to make the start and end orientations match (either because the curve is non-planar, or you applied a total amount of twist that wasn’t an even multiple of 360) is spread out along the entire curve, instead of possibly coming suddenly along the last edge.

Extrapolate End Tangents

Extrapolate the tangent for the last edge from the previous two edges. When this is off, the tangent for the final edge is just the edge direction.

This is most useful when a backbone curve is intended to represent a circular arc, so the end cross sections will be rotated as expected.

Transform Using Curve Point Attributes

Orient the cross-sections using the point attributes P, N, up, orient, rot, trans, pivot, pscale, scale, and/or transform on the spine curve.

  • If N is present and none of up, orient, rot, or transform are present, the node uses N as the curve tangent and computes the rest of the rotation as usual.

  • If up is present and none of N, orient, rot, or transform are present, the node computes the tangent as usual, and uses up as the up-vector at each vertex (before any roll or twist is applied).

UVs and Attributes

UV Coordinates

Compute UVs

Generate a uv vertex attribute on the generated surface. If the input curves already have uv attributes, the node uses the values from those attributes (U corresponds to the cross sections, and V corresponds to the spine curve).

(If Surface Type is "Points", this will generate a point attribute.)

Override Any Existing UVs

When Compute UVs is on, compute new UVs for the surface, even if the input curves already had uv attributes.

Length-Weighted UVs

Scale the U and V coordinates based on proportional edge lengths so they're even across the whole surface, rather than bunching up where edges bunch up.

(If Normalize Computed Us and/or Normalize Computed Vs are on, the coordinates are still normalized to be within the 0 to 1 range.)

Normalize Computed Us

Normalize computed U coordinates to be in the range 0 to 1 (before applying UV scale). When this is off, U corresponds to the average distance around the cross sections on the mesh (ignoring any stretch applied by Stretch Around Turns).

When this is on and Normalize Computed Vs is off, the node scales V such that U and V appear scaled similarly in space (depending on the Use Max Cross Section Length per Curve for Proportional Scale setting).

This is especially useful for things like applying repeating rope textures, where the texture should be applied isotropically.

Normalize Computed Vs

Normalize computed V coordinates to be in the range 0 to 1 (before applying UV scale). When this is off, V corresponds to the average distance along the surface in V, or the distance along the spine curve, depending on the Use Mesh Edge Lengths instead of Curve Edge Lengths parameter.

When this is on and Normalize Computed Us is off, the node scales U such that U and V appear scaled similarly in space.

Flip Computed Us

Reverse the direction of the computed U values (same as replacing each U value with max(U values) - U). Use this if a texture appears backward when applied to the surface.

This should be on for textures to appear correct on surfaces viewed from the front, (normals pointing toward the camera), and should be off for textures to appear correct on surfaces viewed from the back, (normals pointing away from the camera).

UV Scale

UV Scale

A scale on the generated UV coordinates. This is applied after any normalization.

This is applied before the adjustments made by Make Computed Us Wrap Seamlessly and/or Make Computed Vs Wrap Seamlessly, so the texture will still wrap correctly.

Use Mesh Edge Lengths Instead of Curve Edge Lengths

When this is on and Length-Weighted UVs is on, the averages of the output mesh edge lengths in the curve direction are used as the lengths in the V direction, instead of the original curve edge lengths.

  • This is useful when, for example, a curve has coincident points with different cross sections, such as a door jamb in a hallway, so that the surface between the two cross sections gets a non-zero area of texture space.

  • It is also useful for generating UVs for grid end caps. However, it can be less stable, when changing rotations, than using the original curve lengths.

Use Max Cross Section Length per Curve for Proportional Scale

When Normalize Computed Us is on and Normalize Computed Vs is on, this controls whether the node uses the maximum cross section length for computing the V scale, instead of the average of the previous and next cross section lengths for each V edge.

If the cross section length varies significantly, this can make the texture appear stretched in some places, but can also avoid instability and inconsistency in the V scale along the curve.

UV Seams

Snap U to Nearest Boundary

When Normalize Computed Us is off and this is on, the node rounds the range of U to the nearest positive integer, so textures wrap correctly in the U direction. This node applies this rounding after the UV Scale.

Snap V to Nearest Boundary

When Normalize Computed Vs is off and this is on, the node roounds the range of V to the nearest positive integer, so textures wrap correctly in the V direction. This node applies this rounding after the UV Scale.

Attributes

From Backbone Curves

Space-separated list of attributes to copy from the backbone curve onto the generated surface. You can use patterns here.

By default, P, N, up, pscale, scale, orient, rot, pivot, trans, and transform are not copied, to avoid copying attributes used for computing transforms.

From Cross Sections

Space-separated list of attributes to copy from the cross-section curves onto the generated surface. You can use patterns here.

The transforms attributes that have a transform type (position, vector, normal, quaternion, or transform matrix) appropriately.

Output attributes

Point Row Attribute

Create an integer point attribute with this name on the generated surface, containing the row number.

Point Col Attribute

Create an integer point attribute with this name on the generated surface, containing the column number.

Prim Row Attribute

Create an integer point attribute with this name on the generated surface, containing the quad row number.

Prim Col Attribute

Create an integer point attribute with this name on the generated surface, containing the quad column number.

Cross Section Num Attribute

Create an integer point attribute with this name on the generated surface, containing the primitive number of the cross section curve used to create the point.

Curve Num Attribute

Create an integer point attribute with this name on the generated surface, containing the primitive number of the spine curve used to create the point.

Examples

SweepBasic Example for Sweep geometry node

This example demonstrates how the Sweep SOP copies geometry onto the points of a curve.

The Sweep SOP is unique in that it automatically places the copied geometry perpendicular to the backbone it is copied to. Variations such as the Cross Section’s scale can be adjusted using expressions.

SweepCurve Example for Sweep geometry node

This network contains an example of the Sweep SOP. A NURBS curve and NURBS circles are used as the backbone and the cross section geometries of the sweep operation respectively.

By controling the scaling of the cross section geometry in the Sweep SOP various effects can be acheived. Finally, a Skin SOP completes the form by using the swept geometry as a kind of skeleton.

SweepDome Example for Sweep geometry node

In this example the Sweep SOP a grid is used as the backbone of a sweep operation with arcs (created by a Circle SOP) as the hull (cross sections) of the sweep object.

The final sweep object is then skinned with a Skin SOP to create the dome geometry.

WigglyWorm Example for Sweep geometry node

This network demonstrates how the Sweep SOP can be used to construct geometry that is easily deformable. The Sweep SOP requires a backbone and cross section geometry.

Through a sin() function an expression is created to animate the backbone for a slithering effect. Then the circles are copied at every point on the backbone to create the skeleton of the worm. Finally, a simple skin operation completes the worm body.

See also

Geometry nodes

  • Adaptive Prune

    Removes elements while trying to maintain the overall appearance.

  • Add

    Creates Points or Polygons, or adds points/polys to an input.

  • Agent

    Creates agent primitives.

  • Agent Clip

    Adds new clips to agent primitives.

  • Agent Clip Properties

    Defines how agents' animation clips should be played back.

  • Agent Clip Transition Graph

    Creates geometry describing possible transitions between animation clips.

  • Agent Collision Layer

    Creates a new agent layer that is suitable for collision detection.

  • Agent Configure Joints

    Creates point attributes that specify the rotation limits of an agent’s joints.

  • Agent Constraint Network

    Builds a constraint network to hold an agent’s limbs together.

  • Agent Definition Cache

    Writes agent definition files to disk.

  • Agent Edit

    Edits properties of agent primitives.

  • Agent Layer

    Adds a new layer to agent primitives.

  • Agent Look At

    Adjusts the head of an agent to look at a specific object or position.

  • Agent Prep

    Adds various common point attributes to agents for use by other crowd nodes.

  • Agent Proxy

    Provides simple proxy geometry for an agent.

  • Agent Relationship

    Creates parent-child relationships between agents.

  • Agent Terrain Adaptation

    Adapts agents' legs to conform to terrain and prevent the feet from sliding.

  • Agent Transform Group

    Adds new transform groups to agent primitives.

  • Agent Unpack

    Extracts geometry from agent primitives.

  • Agent Vellum Unpack

    Extracts geometry from agent primitives for a Vellum simulation.

  • Alembic

    Loads the geometry from an Alembic scene archive (.abc) file into a geometry network.

  • Alembic Group

    Creates a geometry group for Alembic primitives.

  • Alembic Primitive

    Modifies intrinsic properties of Alembic primitives.

  • Alembic ROP output driver

  • Align

    Aligns a group of primitives to each other or to an auxiliary input.

  • Assemble

    Cleans up a series of break operations and creates the resulting pieces.

  • Attribute Blur

    Blurs out (or "relaxes") points in a mesh or a point cloud.

  • Attribute Cast

    Changes the size/precision Houdini uses to store an attribute.

  • Attribute Composite

    Composites vertex, point, primitive, and/or detail attributes between two or more selections.

  • Attribute Copy

    Copies attributes between groups of vertices, points, or primitives.

  • Attribute Create

    Adds or edits user defined attributes.

  • Attribute Delete

    Deletes point and primitive attributes.

  • Attribute Expression

    Allows simple VEX expressions to modify attributes.

  • Attribute Fade

    Fades a point attribute in and out over time.

  • Attribute Interpolate

    Interpolates attributes within primitives or based on explicit weights.

  • Attribute Mirror

    Copies and flips attributes from one side of a plane to another.

  • Attribute Noise

    Adds noise to attributes of the incoming geometry.

  • Attribute Paint

    Interactively paint point attributes, such as color or deformation mask values, directly on geometry.

  • Attribute Promote

    Promotes or demotes attributes from one geometry level to another.

  • Attribute Randomize

    Generates random attribute values of various distributions.

  • Attribute Remap

    Fits an attribute’s values to a new range.

  • Attribute Rename

    Renames or deletes point and primitive attributes.

  • Attribute Reorient

    Modifies point attributes based on differences between two models.

  • Attribute String Edit

    Edits string attribute values.

  • Attribute Swap

    Copies, moves, or swaps the contents of attributes.

  • Attribute Transfer

    Transfers vertex, point, primitive, and/or detail attributes between two models.

  • Attribute Transfer By UV

    Transfers attributes between two geometries based on UV proximity.

  • Attribute VOP

    Runs a VOP network to modify geometry attributes.

  • Attribute Wrangle

    Runs a VEX snippet to modify attribute values.

  • Attribute from Map

    Samples texture map information to a point attribute.

  • Attribute from Volume

    Copies information from a volume onto the point attributes of another piece of geometry, with optional remapping.

  • Bake ODE

    Converts primitives for ODE and Bullet solvers.

  • Bake Volume

    Computes lighting values within volume primitives

  • Basis

    Provides operations for moving knots within the parametric space of a NURBS curve or surface.

  • Bend

    Applies captures such as bend, twist, taper, and squash/stretch.

  • Blast

    Deletes primitives, points, edges or breakpoints.

  • Blend Shapes

    Computes a 3D metamorphosis between shapes with the same topology.

  • Block Begin

    The start of a looping block.

  • Block Begin Compile

    The start of a compile block.

  • Block End

    The end/output of a looping block.

  • Block End Compile

    The end/output of a compile block.

  • Bone Capture

    Supports Bone Deform by assigning capture weights to bones.

  • Bone Capture Biharmonic

    Supports Deform by assigning capture weights to points based on biharmonic functions on tetrahedral meshes.

  • Bone Capture Lines

    Utility node that supports Bone Capture Biharmonic by creating lines from bones with suitable attributes.

  • Bone Capture Proximity

    Supports Bone Deform by assigning capture weights to points based on distance to bones.

  • Bone Deform

    Uses capture attributes created from bones to deform geometry according to their movement.

  • Bone Link

    Creates default geometry for Bone objects.

  • Boolean

    Combines two polygonal objects with boolean operators, or finds the intersection lines between two polygonal objects.

  • Boolean Fracture

    Fractures the input geometry using cutting surfaces.

  • Bound

    Creates a bounding box, sphere, or rectangle for the input geometry.

  • Box

    Creates a cube or six-sided rectangular box.

  • Bulge

    Deforms the points in the first input using one or more magnets from the second input.

  • COP2 Network

  • Cache

    Records and caches its input geometry for faster playback.

  • Cap

    Closes open areas with flat or rounded coverings.

  • Capture Attribute Pack

    Converts array attributes into a single index-pair capture attribute.

  • Capture Attribute Unpack

    Converts a single index-pair capture attribute into per-point and detail array attributes.

  • Capture Correct

    Adjusts capture regions and capture weights.

  • Capture Layer Paint

    Lets you paint capture attributes directly onto geometry.

  • Capture Mirror

    Copies capture attributes from one half of a symmetric model to the other.

  • Capture Override

    Overrides the capture weights on individual points.

  • Capture Region

    Supports Capture and Deform operation by creating a volume within which points are captured to a bone.

  • Carve

    Slices, cuts or extracts points or cross-sections from a primitive.

  • Channel

    Reads sample data from a chop and converts it into point positions and point attributes.

  • Circle

    Creates open or closed arcs, circles and ellipses.

  • Circle from Edges

    Transforms selected geometry into a circle.

  • Clay

    Lets you deform NURBS faces and NURBS surfaces by pulling points that lie directly on them.

  • Clean

    Helps clean up dirty models.

  • Clip

    Removes or groups geometry on one side of a plane, or creases geometry along a plane.

  • Cloth Capture

    Captures low-res simulated cloth.

  • Cloth Deform

    Deforms geometry captured by the Cloth Capture SOP.

  • Cloud

    Creates a volume representation of source geometry.

  • Cloud Light

    Fills a volume with a diffuse light.

  • Cloud Noise

    Applies a cloud like noise to a Fog volume.

  • Cluster

    Low-level machinery to cluster points based on their positions (or any vector attribute).

  • Cluster Points

    Higher-level node to cluster points based on their positions (or any vector attribute).

  • Collision Source

    Creates geometry and VDB volumes for use with DOPs collisions.

  • Color

    Adds color attributes to geometry.

  • Comb

    Adjust surface point normals by painting.

  • Connect Adjacent Pieces

    Creates lines between nearby pieces.

  • Connectivity

    Creates an attribute with a unique value for each set of connected primitives or points.

  • Control

    Creates simple geometry for use as control shapes.

  • Convert

    Converts geometry from one geometry type to another.

  • Convert HeightField

    Converts a 2D height field to a 3D VDB volume, polygon surface, or polygon soup surface.

  • Convert Line

    Converts the input geometry into line segments.

  • Convert Meta

    Polygonizes metaball geometry.

  • Convert Tets

    Generates the oriented surface of a tetrahedron mesh.

  • Convert VDB

    Converts sparse volumes.

  • Convert VDB Points

    Converts a Point Cloud into a VDB Points Primitive, or vice versa.

  • Convert Volume

    Converts the iso-surface of a volume into a polygonal surface.

  • Convex Decomposition

    Decomposes the input geometry into approximate convex segments.

  • Copy Stamp

    Creates multiple copies of the input geometry, or copies the geometry onto the points of the second input.

  • Copy and Transform

    Copies geometry and applies transformations to the copies.

  • Copy to Curves

    Copies geometry in the first input onto curves of the second input.

  • Copy to Points

    Copies geometry in the first input onto the points of the second input.

  • Crease

    Manually adds or removes a creaseweight attribute to/from polygon edges, for use with the Subdivide SOP.

  • Creep

    Deforms and animates a piece of geometry across a surface.

  • Cross Section Surface

    Creates a surface around cross sections.

  • Crowd Source

    Populates a crowd of agent primitives.

  • Curve

    Creates polygonal, NURBS, or Bezier curves.

  • Curveclay

    Deforms a spline surface by reshaping a curve on the surface.

  • Curvesect

    Finds the intersections (or points of minimum distance) between two or more curves or faces.

  • DOP I/O

    Imports fields from DOP simulations, saves them to disk, and loads them back again.

  • DOP Import Fields

    Imports scalar and vector fields from a DOP simulation.

  • DOP Import Records

    Imports option and record data from DOP simulations into points with point attributes.

  • DOP Network

  • Debris Source

    Generates point emission sources for debris from separating fractured rigid body objects.

  • Deformation Wrangle

    Runs a VEX snippet to deform geometry.

  • Delete

    Deletes input geometry by group, entity number, bounding volume, primitive/point/edge normals, and/or degeneracy.

  • DeltaMush

    Smooths out (or "relaxes") point deformations.

  • Detangle

    Attempts to prevent collisions when deforming geometry.

  • Dissolve

    Deletes edges from the input polygonal geometry merging polygons with shared edges.

  • Distance Along Geometry

    Measures the distance of the shortest path along the geometry’s edges or surfaces from each start point.

  • Distance from Geometry

    Measures distance between each point and a reference geometry.

  • Distance from Target

    Measures distance of each point from a target.

  • Divide

    Divides, smooths, and triangulates polygons.

  • Dop Import

    Imports and transforms geometry based on information extracted from a DOP simulation.

  • Draw Curve

    Creates a curve based on user input in the viewport.

  • Draw Guides

  • Each

    Culls the input geometry according to the specifications of the For Each SOP.

  • Edge Collapse

    Collapses edges and faces to their centerpoints.

  • Edge Cusp

    Sharpens edges by uniquing their points and recomputing point normals.

  • Edge Divide

    Inserts points on the edges of polygons and optionally connects them.

  • Edge Equalize

    Transforms selected edges so that all edges are of equal length.

  • Edge Flip

    Flips the direction of polygon edges.

  • Edge Fracture

    Cuts geometry along edges using guiding curves.

  • Edge Straighten

    Straightens selected edges.

  • Edge Transport

    Copies and optionally modifies attribute values along edges networks and curves.

  • Edit

    Edits points, edges, or faces interactively.

  • Ends

    Closes, opens, or clamps end points.

  • Enumerate

    Sets an attribute on selected points or primitives to sequential numbers or strings.

  • Error

    Generates a message, warning, or error, which can show up on a parent asset.

  • Exploded View

    Pushes geometry out from the center to create an exploded view.

  • Export Object Transforms

    Export transform attributes to object nodes.

  • Extract Centroid

    Computes the centroid of each piece of the geometry.

  • Extract Transform

    Computes the best-fit transform between two pieces of geometry.

  • Extrude

    Extrudes geometry along a normal.

  • Extrude Volume

    Extrudes surface geometry into a volume.

  • FEM Visualization

  • FLIP Source

    Creates a surface or density VDB for sourcing FLIP simulations.

  • Facet

    Controls the smoothness of faceting of a surface.

  • Filament Advect

    Evolves polygonal curves as vortex filaments.

  • File

    Reads, writes, or caches geometry on disk.

  • File Cache

    Writes and reads geometry sequences to disk.

  • File Merge

    Reads and collates data from disk.

  • Fillet

    Creates smooth bridging geometry between two curves or surfaces.

  • Filmbox FBX ROP output driver

  • Find Shortest Path

    Finds the shortest paths from start points to end points, following the edges of a surface.

  • Fit

    Fits a spline curve to points, or a spline surface to a mesh of points.

  • Fluid Compress

    Compresses the output of fluid simulations to decrease size on disk

  • Font

    Creates 3D text from Type 1, TrueType and OpenType fonts.

  • Force

    Uses a metaball to attract or repel points or springs.

  • Fractal

    Creates jagged mountain-like divisions of the input geometry.

  • Fur

    Creates a set of hair-like curves across a surface.

  • Fuse

    Merges points.

  • Geometry nodes

    Geometry nodes live inside Geo objects and generate geometry.

  • Glue Cluster

    Adds strength to a glue constraint network according to cluster values.

  • Grain Source

    Generates particles to be used as sources in a particle-based grain simulation.

  • Graph Color

    Assigns a unique integer attribute to non-touching components.

  • Grid

    Creates planar geometry.

  • Groom Blend

    Blends the guides and skin of two grooms.

  • Groom Fetch

    Fetches groom data from grooming objects.

  • Groom Pack

    Packs the components of a groom into a set of named Packed Primitives for the purpose of writing it to disk.

  • Groom Switch

    Switches between all components of two groom streams.

  • Groom Unpack

    Unpacks the components of a groom from a packed groom.

  • Group

    Generates groups of points, primitives, edges, or vertices according to various criteria.

  • Group Combine

    Combines point groups, primitive groups, or edge groups according to boolean operations.

  • Group Copy

    Copies groups between two pieces of geometry, based on point/primitive numbers.

  • Group Delete

    Deletes groups of points, primitives, edges, or vertices according to patterns.

  • Group Expand

    Expands or shrinks groups of Edges, Points, Primitives, or Vertices.

  • Group Expression

    Runs VEX expressions to modify group membership.

  • Group Find Path

    Constructs groups for paths between elements.

  • Group Paint

    Sets group membership interactively by painting.

  • Group Promote

    Converts point, primitive, edge, or vertex groups into point, primitive, edge, or vertex groups.

  • Group Range

    Groups points and primitives by ranges.

  • Group Rename

    Renames groups according to patterns.

  • Group Transfer

    Transfers groups between two pieces of geometry, based on proximity.

  • Group by Lasso

    Groups points and primitives by lasso.

  • Group from Attribute Boundary

    Creates a group that includes the boundaries of the specified attribute.

  • Guide Advect

    Advects guide points through a velocity volume.

  • Guide Collide With VDB

    Resolves collisions of guide curves with VDB signed distance fields.

  • Guide Deform

    Deforms geometry with an animated skin and optionally guide curves.

  • Guide Groom

    Allows intuitive manipulation of guide curves in the viewport.

  • Guide Group

    Creates standard primitive groups used by grooming tools.

  • Guide Initialize

    Quickly give hair guides some initial direction.

  • Guide Mask

    Creates masking attributes for other grooming operations.

  • Guide Partition

    Creates and prepares parting lines for use with hair generation.

  • Guide Skin Attribute Lookup

    Looks up skin geometry attributes under the root point of guide curves.

  • Guide Tangent Space

    Constructs a coherent tangent space along a curve.

  • Guide Transfer

    Transfer hair guides between geometries.

  • Hair Card Generate

    Converts dense hair curves to a polygon card, keeping the style and shape of the groom.

  • Hair Clump

    Clumps guide curves together.

  • Hair Generate

    Generates hair on a surface or from points.

  • Hair Growth Field

    Generates a velocity field based on stroke primitives.

  • HeightField

    Generates an initial heightfield volume for use with terrain tools.

  • HeightField Blur

    Blurs a terrain height field or mask.

  • HeightField Clip

    Limits height values to a certain minimum and/or maximum.

  • HeightField Copy Layer

    Creates a copy of a height field or mask.

  • HeightField Crop

    Extracts a square of a certain width/length from a larger height volume, or resizes/moves the boundaries of the height field.

  • HeightField Cutout by Object

    Creates a cutout on a terrain based on geometry.

  • HeightField Distort by Layer

    Displaces a height field by another field.

  • HeightField Distort by Noise

    Advects the input volume through a noise pattern to break up hard edges and add variety.

  • HeightField Draw Mask

    Lets you draw shapes to create a mask for height field tools.

  • HeightField Erode

    Calculates thermal and hydraulic erosion over time (frames) to create more realistic terrain.

  • HeightField Erode Hydro

    Simulates the erosion from one heightfield sliding over another for a short time.

  • HeightField Erode Precipitation

    Distributes water along a heightfield. Offers controls for adjusting the intensity, variability, and location of rainfall.

  • HeightField Erode Thermal

    Calculates the effect of thermal erosion on terrain for a short time.

  • HeightField File

    Imports a 2D image map from a file or compositing node into a height field or mask.

  • HeightField Flow Field

    Generates flow and flow direction layers according to the input height layer.

  • HeightField Isolate Layer

    Copies another layer over the mask layer, and optionally flattens the height field.

  • HeightField Layer

    Composites together two height fields.

  • HeightField Layer Clear

    Sets all values in a heightfield layer to a fixed value.

  • HeightField Layer Property

    Sets the border voxel policy on a height field volume.

  • HeightField Mask by Feature

    Creates a mask based on different features of the height layer.

  • HeightField Mask by Object

    Creates a mask based some other geometry.

  • HeightField Mask by Occlusion

    Creates a mask where the input terrain is hollow/depressed, for example riverbeds and valleys.

  • HeightField Noise

    Adds vertical noise to a height field, creating peaks and valleys.

  • HeightField Output

    Exports height and/or mask layers to disk as an image.

  • HeightField Paint

    Lets you paint values into a height or mask field using strokes.

  • HeightField Patch

    Patches features from one heightfield to another.

  • HeightField Pattern

    Adds displacement in the form of a ramps, steps, stripes, Voronoi cells, or other patterns.

  • HeightField Project

    Projects 3D geometry into a height field.

  • HeightField Quick Shade

    Applies a material that lets you plug in textures for different layers.

  • HeightField Remap

    Remaps the values in a height field or mask layer.

  • HeightField Resample

    Changes the resolution of a height field.

  • HeightField Scatter

    Scatters points across the surface of a height field.

  • HeightField Slump

    Simulates loose material sliding down inclines and piling at the bottom.

  • HeightField Terrace

    Creates stepped plains from slopes in the terrain.

  • HeightField Tile Splice

    Stitches height field tiles back together.

  • HeightField Tile Split

    Splits a height field volume into rows and columns.

  • HeightField Transform

    Height field specific scales and offsets.

  • HeightField Visualize

    Visualizes elevations using a custom ramp material, and mask layers using tint colors.

  • Hole

    Makes holes in surfaces.

  • Inflate

    Deforms the points in the first input to make room for the inflation tool.

  • Instance

    Instances Geometry on Points.

  • Intersection Analysis

    Creates points with attributes at intersections between a triangle and/or curve mesh with itself, or with an optional second set of triangles and/or curves.

  • Intersection Stitch

    Composes triangle surfaces and curves together into a single connected mesh.

  • Invoke Compiled Block

    Processes its inputs using the operation of a referenced compiled block.

  • IsoOffset

    Builds an offset surface from geometry.

  • IsoSurface

    Generates an isometric surface from an implicit function.

  • Join

    The Join op connects a sequence of faces or surfaces into a single primitive that inherits their attributes.

  • Knife

    Divides, deletes, or groups geometry based on an interactively drawn line.

  • L-System

    Creates fractal geometry from the recursive application of simple rules.

  • Lattice

    Deforms geometry based on how you reshape control geometry.

  • Lidar Import

    Reads a lidar file and imports a point cloud from its data.

  • Line

    Creates polygon or NURBS lines from a position, direction, and distance.

  • MDD

    Animates points using an MDD file.

  • Magnet

    Deforms geometry by using another piece of geometry to attract or repel points.

  • Match Axis

    Aligns the input geometry to a specific axis.

  • Match Size

    Resizes and recenters the geometry according to reference geometry.

  • Match Topology

    Reorders the primitive and point numbers of the input geometry to match some reference geometry.

  • Material

    Assigns one or more materials to geometry.

  • Measure

    Measures area, volume, or curvature of individual elements or larger pieces of a geometry and puts the results in attributes.

  • Merge

    Merges geometry from its inputs.

  • MetaGroups

    Defines groupings of metaballs so that separate groupings are treated as separate surfaces when merged.

  • Metaball

    Creates metaballs and meta-superquadric surfaces.

  • Mirror

    Duplicates and mirrors geometry across a mirror plane.

  • Mountain

    Displaces points along their normals based on fractal noise.

  • Muscle Capture

    Supports Muscle Deform by assigning capture weights to points based on distance away from given primitives

  • Muscle Deform

    Deforms a surface mesh representing skin to envelop or drape over geometry representing muscles

  • Name

    Creates a "naming" attribute on points or primitives allowing you to refer to them easily, similar to groups.

  • Normal

    Computes surface normal attribute.

  • Null

    Does nothing.

  • Object Merge

    Merges geometry from multiple sources and allows you to define the manner in which they are grouped together and transformed.

  • Object_musclerig@musclerigstrokebuilder

  • Object_riggedmuscle@musclestrokebuilder

    Assists the creation of a Muscle or Muscle Rig by allowing you to draw a stroke on a projection surface.

  • Ocean Evaluate

    Deforms input geometry based on ocean "spectrum" volumes.

  • Ocean Foam

    Generates particle-based foam

  • Ocean Source

    Generates particles and volumes from ocean "spectrum" volumes for use in simulations

  • Ocean Spectrum

    Generates volumes containing information for simulating ocean waves.

  • Ocean Waves

    Instances individual waveforms onto input points and generated points.

  • OpenCL

    Executes an OpenCL kernel on geometry.

  • Orientation Along Curve

    Computes orientations (frames) along curves.

  • Output

    Marks the output of a sub-network.

  • Pack

    Packs geometry into an embedded primitive.

  • Pack Points

    Packs points into a tiled grid of packed primitives.

  • Packed Disk Edit

    Editing Packed Disk Primitives.

  • Packed Edit

    Editing Packed Primitives.

  • Paint Color Volume

    Creates a color volume based on drawn curve

  • Paint Fog Volume

    Creates a fog volume based on drawn curve

  • Paint SDF Volume

    Creates an SDF volume based on drawn curve

  • Particle Fluid Surface

    Generates a surface around the particles from a particle fluid simulation.

  • Particle Fluid Tank

    Creates a set of regular points filling a tank.

  • Partition

    Places points and primitives into groups based on a user-supplied rule.

  • Peak

    Moves primitives, points, edges or breakpoints along their normals.

  • Planar Patch

    Creates a planar polygonal patch.

  • Planar Patch from Curves

    Fills in a 2d curve network with triangles.

  • Planar Pleat

    Deforms flat geometry into a pleat.

  • Platonic Solids

    Creates platonic solids of different types.

  • Point Cloud Iso

    Constructs an iso surface from its input points.

  • Point Deform

    Deforms geometry on an arbitrary connected point mesh.

  • Point Generate

    Creates new points, optionally based on point positions in the input geometry.

  • Point Jitter

    Jitters points in random directions.

  • Point Relax

    Moves points with overlapping radii away from each other, optionally on a surface.

  • Point Replicate

    Generates a cloud of points around the input points.

  • Point Split

    Splits points shared by multiple vertices, optionally only if the vertices differ in attribute values.

  • Point Velocity

    Computes and manipulates velocities for points of a geometry.

  • Point Weld

    Merges points interactively.

  • Points from Volume

    Creates set of regular points filling a volume.

  • Poly Bridge

    Creates flat or tube-shaped polygon surfaces between source and destination edge loops, with controls for the shape of the bridge.

  • Poly Expand 2D

    Creates offset polygonal geometry for planar polygonal graphs.

  • Poly Extrude

    Extrudes polygonal faces and edges.

  • PolyBevel

    Creates straight, rounded, or custom fillets along edges and corners.

  • PolyCut

    Breaks curves where an attribute crosses a threshold.

  • PolyDoctor

    Helps repair invalid polygonal geometry, such as for cloth simulation.

  • PolyFill

    Fills holes with polygonal patches.

  • PolyFrame

    Creates coordinate frame attributes for points and vertices.

  • PolyLoft

    Creates new polygons using existing points.

  • PolyPatch

    Creates a smooth polygonal patch from primitives.

  • PolyPath

    Cleans up topology of polygon curves.

  • PolyReduce

    Reduces the number of polygons in a model while retaining its shape. This node preserves features, attributes, textures, and quads during reduction.

  • PolySoup

    Combines polygons into a single primitive that can be more efficient for many polygons

  • PolySpline

    The PolySpline SOP fits a spline curve to a polygon or hull and outputs a polygonal approximation of that spline.

  • PolySplit

    Divides an existing polygon into multiple new polygons.

  • PolyWire

    Constructs polygonal tubes around polylines, creating renderable geometry with smooth bends and intersections.

  • Pose-Space Deform

    Interpolates between a set of pose-shapes based on the value of a set of drivers.

  • Pose-Space Deform Combine

    Combine result of Pose-Space Deform with rest geometry.

  • Pose-Space Edit

    Packs geometry edits for pose-space deformation.

  • Pose-Space Edit Configure

    Creates common attributes used by the Pose-Space Edit SOP.

  • Primitive

    Edits primitive, primitive attributes, and profile curves.

  • Profile

    Extracts or manipulates profile curves.

  • Project

    Creates profile curves on surfaces.

  • Pyro Post-Process

    Applies common post-processing effects to the results of Pyro solves.

  • Pyro Solver

    Runs a dynamic Pyro simulation.

  • Pyro Source

    Creates points for sourcing pyro and smoke simulations.

  • Pyro Source Spread

    Pyro Source Spread solves for the spreading of flame across a point cloud.

  • Python

    Runs a Python snippet to modify the incoming geometry.

  • RBD Bullet Solver

    Runs a dynamic Bullet simulation.

  • RBD Cluster

    Combines fractured pieces or constraints into larger clusters.

  • RBD Configure

    Packs and creates attributes describing rigid body objects.

  • RBD Connected Faces

    Stores the primitive number and distance to the opposite face on the inside faces of fractured geometry.

  • RBD Constraint Properties

    Creates attributes describing rigid body constraints.

  • RBD Constraints From Curves

    Creates rigid body constraint geometry from curves drawn in the viewport.

  • RBD Constraints From Lines

    Creates rigid body constraint geometry from interactively drawn lines in the viewport.

  • RBD Constraints From Rules

    Creates rigid body constraint geometry from a set of rules and conditions.

  • RBD Convert Constraints

    Converts existing constraint prims into constraints with different anchor positions.

  • RBD Deform Pieces

    Deforms geometry with simulated proxy geometry.

  • RBD Disconnected Faces

    Detects when connected faces have become separated.

  • RBD Exploded View

    Merges RBD fractured geometry with the proxy geometry and pushes it out from the center to create an exploded view.

  • RBD I/O

    Packs RBD fractured geometry, saves them to disk, and loads them back again.

  • RBD Interior Detail

    Creates additional detail on the interior surfaces of fractured geometry.

  • RBD Material Fracture

    Fractures the input geometry based on a material type.

  • RBD Pack

    Packs RBD geometry, constraints, and proxy geometry into a single geometry.

  • RBD Paint

    Paints values onto geometry or constraints using strokes.

  • RBD Unpack

    Unpacks an RBD setup into three outputs.

  • RMan Shader

    Attaches RenderMan shaders to groups of faces.

  • ROP Geometry Output

  • Rails

    Generates surfaces by stretching cross-sections between two guide rails.

  • Ray

    Projects one surface onto another.

  • Refine

    Increases the number of points/CVs in a curve or surface without changing its shape.

  • Reguide

    Scatters new guides, interpolating the properties of existing guides.

  • Remesh

    Recreates the shape of the input surface using "high-quality" (nearly equilateral) triangles.

  • Repack

    Repacks geometry as an embedded primitive.

  • Resample

    Resamples one or more curves or surfaces into even length segments.

  • Rest Position

    Sets the alignment of solid textures to the geometry so the texture stays put on the surface as it deforms.

  • Retime

    Retimes the time-dependent input geometry.

  • Reverse

    Reverses or cycles the vertex order of faces.

  • Revolve

    Revolves a curve around a center axis to sweep out a surface.

  • Rewire Vertices

    Rewires vertices to different points specified by an attribute.

  • Ripple

    Generates ripples by displacing points along the up direction specified.

  • Ripple

    Generates ripples by displacing points along the up direction specified.

  • Scatter

    Scatters new points randomly across a surface or through a volume.

  • Script

    Runs scripts when cooked.

  • Sculpt

    Lets you interactively reshape a surface by brushing.

  • Sequence Blend

    Morphs though a sequence of 3D shapes, interpolating geometry and attributes.

  • Shape Diff

    Computes the post-deform or pre-deform difference of two geometries with similar topologies.

  • Shrinkwrap

    Computes the convex hull of the input geometry and moves its polygons inwards along their normals.

  • Skin

    Builds a skin surface between any number of shape curves.

  • Sky

    Creates a sky filled with volumentric clouds

  • Smooth

    Smooths out (or "relaxes") polygons, meshes and curves without increasing the number of points.

  • Soft Peak

    Moves the selected point along its normal, with smooth rolloff to surrounding points.

  • Soft Transform

    Moves the selected point, with smooth rolloff to surrounding points.

  • Solid Conform

    Creates a tetrahedral mesh that conforms to a connected mesh as much as possible.

  • Solid Embed

    Creates a simple tetrahedral mesh that covers a connected mesh.

  • Solid Fracture

    Creates a partition of a tetrahedral mesh that can be used for finite-element fracturing.

  • Solver

    Allows running a SOP network iteratively over some input geometry, with the output of the network from the previous frame serving as the input for the network at the current frame.

  • Sort

    Reorders points and primitives in different ways, including randomly.

  • Sphere

    Creates a sphere or ovoid surface.

  • Split

    Splits primitives or points into two streams.

  • Spray Paint

    Spray paints random points onto a surface.

  • Sprite

    A SOP node that sets the sprite display for points.

  • Starburst

    Insets points on polygonal faces.

  • Stash

    Caches the input geometry in the node on command, and then uses it as the node’s output.

  • Stitch

    Stretches two curves or surfaces to cover a smooth area.

  • Stroke

    Low level tool for building interactive assets.

  • Subdivide

    Subdivides polygons into smoother, higher-resolution polygons.

  • Subnetwork

    The Subnet op is essentially a way of creating a macro to represent a collection of ops as a single op in the Network Editor.

  • Super Quad

    Generates an isoquadric surface.

  • Surfsect

    Trims or creates profile curves along the intersection lines between NURBS or bezier surfaces.

  • Sweep

    Creates a surface by sweeping a cross section curve along a spine curve.

  • Switch

    Switches between network branches based on an expression or keyframe animation.

  • Switch-If

    Switches between two network branches based on an expression or geometry test.

  • TOP Geometry

    Sends input geometry to a TOP subnet and retrieves the output geometry.

  • Table Import

    Reads a CSV file creating point per row.

  • Test Geometry: Crag

    Creates a rock creature, which can be used as test geometry.

  • Test Geometry: Pig Head

    Creates a pig head, which can be used as test geometry..

  • Test Geometry: Rubber Toy

    Creates a rubber toy, which can be used as test geometry.

  • Test Geometry: Shader Ball

    Creates a shader ball, which can be used to test shaders.

  • Test Geometry: Squab

    Creates a squab, which can be used as test geometry.

  • Test Geometry: Tommy

    Creates a soldier, which can be used as test geometry.

  • Test Simulation: Crowd Transition

    Provides a simple crowd simulation for testing transitions between animation clips.

  • Test Simulation: Ragdoll

    Provides a simple Bullet simulation for testing the behavior of a ragdoll.

  • Tet Partition

    Partitions a given tetrahedron mesh into groups of tets isolated by a given polygon mesh

  • Tetrahedralize

    Performs variations of a Delaunay Tetrahedralization.

  • TimeShift

    Cooks the input at a different time.

  • Toon Shader Attributes

    Sets attributes used by the Toon Color Shader and Toon Outline Shader.

  • TopoBuild

    Lets you interactively draw a reduced quad mesh automatically snapped to existing geometry.

  • Torus

    Creates a torus (doughnut) shaped surface.

  • Trace

    Traces curves from an image file.

  • Trail

    Creates trails behind points.

  • Transform

    The Transform operation transforms the source geometry in "object space" using a transformation matrix.

  • Transform Axis

    Transforms the input geometry relative to a specific axis.

  • Transform By Attribute

    Transforms the input geometry by a point attribute.

  • Transform Pieces

    Transforms input geometry according to transformation attributes on template geometry.

  • Tri Bezier

    Creates a triangular Bezier surface.

  • TriDivide

    Refines triangular meshes using various metrics.

  • Triangulate 2D

    Connects points to form well-shaped triangles.

  • Trim

    Trims away parts of a spline surface defined by a profile curve or untrims previous trims.

  • Tube

    Creates open or closed tubes, cones, or pyramids.

  • UV Autoseam

    Generates an edge group representing suggested seams for flattening a polygon model in UV space.

  • UV Brush

    Adjusts texture coordinates in the UV viewport by painting.

  • UV Edit

    Lets you interactively move UVs in the texture view.

  • UV Flatten

    Creates flattened pieces in texture space from 3D geometry.

  • UV Fuse

    Merges UVs.

  • UV Layout

    Packs UV islands efficiently into a limited area.

  • UV Pelt

    Relaxes UVs by pulling them out toward the edges of the texture area.

  • UV Project

    Assigns UVs by projecting them onto the surface from a set direction.

  • UV Quick Shade

    Applies an image file as a textured shader to a surface.

  • UV Texture

    Assigns texture UV coordinates to geometry for use in texture and bump mapping.

  • UV Transform

    Transforms UV texture coordinates on the source geometry.

  • UV Unwrap

    Separates UVs into reasonably flat, non-overlapping groups.

  • Unix

    Processes geometry using an external program.

  • Unpack

    Unpacks packed primitives.

  • Unpack Points

    Unpacks points from packed primitives.

  • Unpack USD

    Converts "packed USD" primitives into normal Houdini geometry.

  • VDB

    Creates one or more empty/uniform VDB volume primitives.

  • VDB Activate

    Activates voxel regions of a VDB for further processing.

  • VDB Activate SDF

    Expand or contract signed distance fields stored on VDB volume primitives.

  • VDB Advect

    Moves VDBs in the input geometry along a VDB velocity field.

  • VDB Advect Points

    Moves points in the input geometry along a VDB velocity field.

  • VDB Analysis

    Computes an analytic property of a VDB volumes, such as gradient or curvature.

  • VDB Clip

    Clips VDB volume primitives using a bounding box or another VDB as a mask.

  • VDB Combine

    Combines the values of two aligned VDB volumes in various ways.

  • VDB Diagnostics

    Tests VDBs for Bad Values and Repairs.

  • VDB Fracture

    Cuts level set VDB volume primitives into multiple pieces.

  • VDB LOD

    Build an LOD Pyramid from a VDB.

  • VDB Morph SDF

    Blends between source and target SDF VDBs.

  • VDB Occlusion Mask

    Create a mask of the voxels in shadow from a camera for VDB primitives.

  • VDB Points Delete

    Deletes points inside of VDB Points primitives.

  • VDB Points Group

    Manipulates the Internal Groups of a VDB Points Primitive.

  • VDB Potential Flow

    Computes the steady-state air flow around VDB obstacles.

  • VDB Project Non-Divergent

    Removes divergence from a Vector VDB.

  • VDB Renormalize SDF

    Fixes signed distance fields stored in VDB volume primitives.

  • VDB Resample

    Re-samples a VDB volume primitive into a new orientation and/or voxel size.

  • VDB Reshape SDF

    Reshapes signed distance fields in VDB volume primitives.

  • VDB Segment by Connectivity

    Splits SDF VDBs into connected components.

  • VDB Smooth

    Smooths out the values in a VDB volume primitive.

  • VDB Smooth SDF

    Smooths out SDF values in a VDB volume primitive.

  • VDB Topology to SDF

    Creates an SDF VDB based on the active set of another VDB.

  • VDB Vector Merge

    Merges three scalar VDB into one vector VDB.

  • VDB Vector Split

    Splits a vector VDB primitive into three scalar VDB primitives.

  • VDB Visualize Tree

    Replaces a VDB volume with geometry that visualizes its structure.

  • VDB from Particle Fluid

    Generates a signed distance field (SDF) VDB volume representing the surface of a set of particles from a particle fluid simulation.

  • VDB from Particles

    Converts point clouds and/or point attributes into VDB volume primitives.

  • VDB from Polygons

    Converts polygonal surfaces and/or surface attributes into VDB volume primitives.

  • VDB to Spheres

    Fills a VDB volume with adaptively-sized spheres.

  • Vellum Configure Grain

    Configures geometry for Vellum Grain constraints.

  • Vellum Constraints

    Configure constraints on geometry for the Vellum solvers.

  • Vellum Drape

    Vellum solver setup to pre-roll fabric to drape over characters.

  • Vellum I/O

    Packs Vellum simulations, saves them to disk, and loads them back again.

  • Vellum Pack

    Packs Vellum geometry and constraints into a single geometry.

  • Vellum Post-Process

    Applies common post-processing effects to the result of Vellum solves.

  • Vellum Reference Frame

    Ties vellum points to a reference frame defined by moving geometry.

  • Vellum Rest Blend

    Blends the current rest values of constraints with a rest state calculated from external geometry.

  • Vellum Solver

    Runs a dynamic Vellum simulation.

  • Vellum Unpack

    Unpacks a Vellum simulation into two outputs.

  • Verify BSDF

    Verify that a bsdf conforms to the required interface.

  • Vertex

    Manually adds or edits attributes on vertices (rather than on points).

  • Visibility

    Shows/hides primitives in the 3D viewer and UV editor.

  • Visualize

    Lets you attach visualizations to different nodes in a geometry network.

  • Volume

    Creates a volume primitive.

  • Volume Analysis

    Computes analytic properties of volumes.

  • Volume Arrival Time

    Computes a speed-defined travel time from source points to voxels.

  • Volume Blur

    Blurs the voxels of a volume.

  • Volume Bound

    Bounds voxel data.

  • Volume Break

    Cuts polygonal objects using a signed distance field volume.

  • Volume Compress

    Re-compresses Volume Primitives.

  • Volume Convolve 3×3×3

    Convolves a volume by a 3×3×3 kernel.

  • Volume FFT

    Compute the Fast Fourier Transform of volumes.

  • Volume Feather

    Feathers the edges of volumes.

  • Volume Merge

    Flattens many volumes into one volume.

  • Volume Mix

    Combines the scalar fields of volume primitives.

  • Volume Optical Flow

    Translates the motion between two "image" volumes into displacement vectors.

  • Volume Patch

    Fill in a region of a volume with features from another volume.

  • Volume Ramp

    Remaps a volume according to a ramp.

  • Volume Rasterize

    Rasterizes into a volume.

  • Volume Rasterize Attributes

    Samples point attributes into VDBs.

  • Volume Rasterize Curve

    Converts a curve into a volume.

  • Volume Rasterize Hair

    Converts fur or hair to a volume for rendering.

  • Volume Rasterize Particles

    Converts a point cloud into a volume.

  • Volume Rasterize Points

    Converts a point cloud into a volume.

  • Volume Reduce

    Reduces the values of a volume into a single number.

  • Volume Resample

    Resamples the voxels of a volume to a new resolution.

  • Volume Resize

    Resizes the bounds of a volume without changing voxels.

  • Volume SDF

    Builds a Signed Distance Field from an isocontour of a volume.

  • Volume Slice

    Extracts 2d slices from volumes.

  • Volume Splice

    Splices overlapping volume primitives together.

  • Volume Stamp

    Stamps volumes instanced on points into a single target volume.

  • Volume Surface

    Adaptively surfaces a volume hierarchy with a regular triangle mesh.

  • Volume Trail

    Computes a trail of points through a velocity volume.

  • Volume VOP

    Runs CVEX on a set of volume primitives.

  • Volume Velocity

    Computes a velocity volume.

  • Volume Velocity from Curves

    Generates a volume velocity field using curve tangents.

  • Volume Velocity from Surface

    Generates a velocity field within a surface geometry.

  • Volume Visualization

    Adjusts attributes for multi-volume visualization.

  • Volume Wrangle

    Runs a VEX snippet to modify voxel values in a volume.

  • Volume from Attribute

    Sets the voxels of a volume from point attributes.

  • Voronoi Fracture

    Fractures the input geometry by performing a Voronoi decomposition of space around the input cell points

  • Voronoi Fracture Points

    Given an object and points of impact on the object, this SOP generates a set of points that can be used as input to the Voronoi Fracture SOP to simulate fracturing the object from those impacts.

  • Voronoi Split

    Cuts the geometry into small pieces according to a set of cuts defined by polylines.

  • Vortex Force Attributes

    Creates the point attributes needed to create a Vortex Force DOP.

  • Whitewater Source

    Generates volumes to be used as sources in a whitewater simulation.

  • Winding Number

    Computes generalized winding number of surface at query points.

  • Wire Blend

    Morphs between curve shapes while maintaining curve length.

  • Wire Capture

    Captures surfaces to a wire, allowing you to edit the wire to deform the surface.

  • Wire Deform

    Deforms geometry captured to a curve via the Wire Capture node.

  • Wire Transfer

    Transfers the shape of one curve to another.

  • Wireframe

    Constructs polygonal tubes around polylines, creating renderable geometry.

  • _heightfield_common

  • _vellum_common

  • glTF ROP output driver

  • posescope

    Assigns channel paths and/or pickscripts to geometry.

  • standard_crowdsim_parms