Houdini 20.0 Nodes Object nodes

Switcher object node

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

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Wire multiple Camera objects into this node’s input, then set or animate the Switch Camera parameter to control which camera’s view the switcher node passes through. Use this switcher as the “camera” for a render node to render the switches.

This object acts like a regular Houdini camera, except that it gets all of its parameters (including transforms) from the input camera. This node has its own rotoscoping options.

Parameters

Render

Switch Camera

Determines which camera to view through - All of the transform and viewing - parameters of the input camera are used.

Display

Whether or not this object is displayed. Turn on the checkbox to have Houdini use this parameter, then set the value to 0 to hide the object, or 1 to show the object. If the checkbox is off, Houdini ignores the value. To see the object in the viewport you must first create a geometry for viewing. To do this dive into the switcher node and add a geometry such as a sphere. You will now be able to see the active camera with a sphere around it.

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.

Output

Override Camera Resolution

Override the camera resolution used.

Resolution Scale

How to override the camera resolution. A scale factor may be chosen or if set to User Specified Resolution, the values in the Resolution parameter below is used.

Resolution

If Resolution Scale is set to User Specified Resolution, then these values are used to override the camera resolution. Standard presets are available via the pull down menu to the right of the parameter.

Pixel Aspect Ratio

Houdini render property
aspect_override

The pixel aspect ratio represents the width of a pixel divided by the height of a pixel. It is not the aspect ratio of the image (which is determined by the resolution of the image). This parameter does not affect rendering, it is only used to change how images are displayed, by stretching the pixels by this factor.

Examples

switchcamera Example for Switcher object node

In this example, we demonstrate how a switcher node can be used to switch the view between two cameras and then used by the render node to output the scene.

Object nodes

  • Agent Cam

    Create and attach camera to a crowd agent.

  • Alembic Archive

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

  • Alembic Xform

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

  • Ambient Light

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

  • Auto Bone Chain Interface

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

  • Blend

    Switches or blends between the transformations of several input objects.

  • Blend Sticky

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

  • Bone

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

  • Camera

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

  • Common object parameters

  • Dop Network

    The DOP Network Object contains a dynamic simulation.

  • Environment Light

    Environment Lights provide background illumination from outside the scene.

  • Extract Transform

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

  • Fetch

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

  • Formation Crowd Example

    Crowd example showing a changing formation setup

  • Fuzzy Logic Obstacle Avoidance Example

  • Fuzzy Logic State Transition Example

  • Geometry

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

  • Groom Merge

    Merges groom data from multiple objects into one.

  • Guide Deform

    Moves the curves of a groom with animated skin.

  • Guide Groom

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

  • Guide Simulate

    Runs a physics simulation on the input guides.

  • Hair Card Generate

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

  • Hair Card Texture Example

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

  • Hair Generate

    Generates hair from a skin geometry and guide curves.

  • Handle

    The Handle Object is an IK tool for manipulating bones.

  • Indirect Light

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

  • Instance

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

  • LOP Import

    Imports transform data from a USD primitive in a LOP node.

  • LOP Import Camera

    Imports a USD camera primitive from a LOP node.

  • Labs Fire Presets

    Quickly generate and render fire simulations using presets for size varying from torch to small to 1m high and low

  • Light

    Light Objects cast light on other objects in a scene.

  • Light template

    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.

  • Microphone

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

  • Mocap Acclaim

    Import Acclaim motion capture.

  • Mocap Biped 1

    A male character with motion captured animations.

  • Mocap Biped 2

    A male character with motion captured animations.

  • Mocap Biped 3

    A male character with motion captured animations.

  • Null

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

  • Path

    The Path object creates an oriented curve (path)

  • PathCV

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

  • Python Script

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

  • Ragdoll Run Example

    Crowd example showing a simple ragdoll setup.

  • Reference Image

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

  • Rivet

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

  • Simple Biped

    A simple and efficient animation rig with full controls.

  • Simple Female

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

  • Simple Male

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

  • Sound

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

  • Stadium Crowds Example

    Crowd example showing a stadium setup

  • Stereo Camera Rig

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

  • Stereo Camera Template

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

  • Sticky

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

  • Street Crowd Example

    Crowd example showing a street setup with two agent groups

  • Subnet

    Container for objects.

  • Switcher

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

  • TOP Network

    The TOP Network operator contains object-level nodes for running tasks.

  • VR Camera

    Camera supporting VR image rendering.

  • Viewport Isolator

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

  • glTF