# Rivet object node

Creates a rivet on an objects surface, usually for parenting.

The Rivet Object gets its world transform from the surface of another object. This tool is useful for attaching objects to deforming surfaces in animation. For example, you can use this tool to attach a saddle to a running horse by creating the rivet on the horse’s back and parenting it to the saddle.

When calculating the transform, points defined in the Point Group parameter are obtained from the Rivet Geometry.

The centroid of these points is designated as the origin of the rivet coordinate frame. The x-axis of that frame is defined by the first two points and the xy-plane of the frame is defined by the first three points.

Alternatively, the rivet can build its coordinate frame based on point attributes of the base surface.

## Rivet

Rivet Geometry

The SOP to attach the geometry to.

Point Group

The point group (or point numbers) based on which the local surface frame is built. Group centroid is set as the frame origin. The x-axis of the frame is defined by first two points.

The z-axis is perpendicular to the plane defined by first three points. If the point group contains only one or two points, the frame axes are world aligned.

Point Weights

The weights assigned to the first three points in the group. This parameter allows to fine tune the exact position of the rivet origin on the plane constructed from the first three points. For example, the weights (0.5, 0.5, 0) will place the origin half way between the first and the second point. Note that the weights should not sum up to 0. The points beyond the third one, if any, are assigned the weight values of 1.

Use Point Vector Attributes For Rivet Frame

With this option turned on, the rivet coordinate frame is calculated based on the point attributes specified in the parameters X-Axis Attribute and Z-Axis Attribute. For all points determined by the Point Group parameter, the attributes are evaluated for the base geometry and averaged out to yield two vectors X and Z that will determine the final x-axis and z-axis of the rivet coordinate frame. If the two average vectors X and Z are not orthogonal, before calculating the x-axis, the X vector is replaced with a vector that lies in the X-Z plane and that is perpendicular to the Z vector.

If this option is turned off then the rivet uses the method for frame calculation described in Point Group parameter help above.

X-Axis Attribute

The name of an attribute used for the calculation of the x-axis in the rivet coordinate frame. This has to be a point attribute of a vector type.

Z-Axis Attribute

The name of an attribute used for the calculation of the z-axis in the rivet coordinate frame. This has to be a point attribute of a vector type.

## Misc

Set Wireframe Color

Use the specified wireframe color

Wireframe Color

The display color of the object

Viewport Selecting Enabled

Object is capable of being picked in the viewport.

Select Script

Script to run when the object is picked in the viewport. See select scripts .

Cache Object Transform

Caches object transforms once Houdini calculates them. This is especially useful for objects whose world space position is expensive to calculate (such as Sticky objects), and objects at the end of long parenting chains (such as Bones). This option is turned on by default for Sticky and Bone objects.

See the OBJ Caching section of the Houdini Preferences window for how to control the size of the object transform cache.

Geometry Scale

Uniform scaling about the xyz axes.

Display

Whether to display only the icon, only the axis, or both.

Icon

Displays only the icon geometry.

Axis

Displays only the axis.

Icon and Axis

Displays both the icon and axis.

Control Type

Switches between the type of geometry to display.

Null

Displays null geometry (i.e. cross).

Circles

Displays circle primitives.

Box

Displays box primitive.

Planes

Displays plane primitives.

Null and Circles

Displays null and circle primitives.

Null and Box

Displays null and box primitives.

Null and Planes

Displays null and plane primitives.

Custom

If an input source is specified, this option will display the geometry of the input.

Orientation

Used in conjunction with circle or plane primitives. Determines which circles or planes to display.

All planes

Displays circle or plane primitives on the YZ, ZX and XY planes.

YZ plane

Displays a circle or plane primitive on the YZ plane.

ZX plane

Displays a circle or plane primitive on the ZX plane.

XY plane

Displays a circle or plane primitive on the XY plane.

YZ, ZX planes

Displays circle or plane primitives on the YZ and ZX planes.

YZ, XY planes

Displays circle or plane primitives on the YZ and XY planes.

ZX, XY planes

Displays circle or plane primitives on the ZX and XY planes.

Determines whether to display the primitives as shaded objects or as wireframe objects.

off

Displays primitives in wireframe mode.

on

Displays primitives in shaded mode.

## Examples

RivetWaveform Example for Rivet object node

In this example, a Waveform deformer is applied to a grid. A Rivet is then attached to the surface of the grid, and then parented to a sphere.

# Object nodes

• Create and attach camera to a crowd agent.

• Loads the objects from an Alembic scene archive (.abc) file into the object level.

• Loads only the transform from an object or objects in an Alembic scene archive (.abc).

• Adds a constant level of light to every surface in the scene (or in the light’s mask), coming from no specific direction.

• The Auto Bone Chain Interface is created by the IK from Objects and IK from Bones tools on the Rigging shelf.

• Switches or blends between the transformations of several input objects.

• Computes its transform by blending between the transforms of two or more sticky objects, allowing you to blend a position across a polygonal surface.

• The Bone Object is used to create hierarchies of limb-like objects that form part of a hierarchy …

• You can view your scene through a camera, and render from its point of view.

• The DOP Network Object contains a dynamic simulation.

• Environment Lights provide background illumination from outside the scene.

• The Extract Transform Object gets its transform by comparing the points of two pieces of geometry.

• The Fetch Object gets its transform by copying the transform of another object.

• Crowd example showing a changing formation setup

• Creates a custom muscle by combining any number of geometry objects, muscle rigs, and muscle pins.

• Container for the geometry operators (SOPs) that define a modeled object.

• Merges groom data from multiple objects into one.

• Moves the curves of a groom with animated skin.

• Generates guide curves from a skin geometry and does further processing on these using an editable SOP network contained within the node.

• Runs a physics simulation on the input guides.

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

• An example of how to create a texture for hair cards.

• Generates hair from a skin geometry and guide curves.

• The Handle Object is an IK tool for manipulating bones.

• Indirect lights produce illumination that has reflected from other objects in the scene.

• Instance Objects can instance other geometry, light, or even subnetworks of objects.

• Light Objects cast light on other objects in a scene.

• A very limited light object without any built-in render properties. Use this only if you want to build completely custom light with your choice of properties.

• The Microphone object specifies a listening point for the SpatialAudio CHOP.

• Import Acclaim motion capture.

• A male character with motion captured animations.

• A male character with motion captured animations.

• A male character with motion captured animations.

• The Muscle object is a versatile tool that can be used when rigging characters and creatures with musculature.

• Creates a simple rigging component for attaching regions of a Franken Muscle to your character rig.

• Creates the internal components of a muscle (the rig), by stroking a curve onto a skin object.

• Serves as a place-holder in the scene, usually for parenting. this object does not render.

• Object nodes represent objects in the scene, such as character parts, geometry objects, lights, cameras, and so on.

• The Path object creates an oriented curve (path)

• The PathCV object creates control vertices used by the Path object.

• Pxr AOV Light object for RenderMan RIS.

• Pxr Barn Light Filter object for RenderMan RIS.

• Pxr Blocker Light Filter object for RenderMan RIS.

• Pxr Cookie Light Filter object for RenderMan RIS.

• Pxr Day Light object for RenderMan RIS.

• Pxr Disk Light object for RenderMan RIS.

• Pxr Distant Light object for RenderMan RIS.

• Pxr Dome Light object for RenderMan RIS.

• Pxr Gobo Light Filter object for RenderMan RIS.

• Pxr Mesh Light object for RenderMan RIS.

• Pxr Portal Light object for RenderMan RIS.

• Pxr Ramp Light Filter object for RenderMan RIS.

• Pxr Rectangle Light object for RenderMan RIS.

• Pxr Rod Light Filter object for RenderMan RIS.

• Pxr Sphere Light object for RenderMan RIS.

• The Python Script object is a container for the geometry operators (SOPs) that define a modeled object.

• Crowd example showing a simple ragdoll setup.

• Container for the Compositing operators (COP2) that define a picture.

• Creates a rivet on an objects surface, usually for parenting.

• A simple and efficient animation rig with full controls.

• A simple and efficient female character animation rig with full controls.

• A simple and efficient male character animation rig with full controls.

• The Sound object defines a sound emission point for the Spatial Audio chop.

• Crowd example showing a stadium setup

• Provides parameters to manipulate the interaxial lens distance as well as the zero parallax setting plane in the scene.

• Serves as a basis for constructing a more functional stereo camera rig as a digital asset.

• Creates a sticky object based on the UV’s of a surface, usually for parenting.

• Crowd example showing a street setup with two agent groups

• Container for objects.

• Acts as a camera but switches between the views from other cameras.

• Collects muscles, anatomical bone models, and skin objects and places them into a single dynamics simulation.

• A ready-to-animate Toon Character.

• The TOP Network Object contains nodes to running tasks

• Camera supporting VR image rendering.

• A Python Script HDA providing per viewport isolation controls from selection.

• pxr Int Mult Light Filter object for RenderMan RIS.