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labs overview sop

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lop

filter: all attributes cameras collections combine constraints context_options crowds geometry import instancing lights materials primitive rendering test_geometry transform utility variants view


all

Add Variant Adds one or more variants to a variant set on a primitive. This node creates the primitive if it doesn’t exist.

Additional Render Vars Create multiple render vars.

Assign Material Assigns a material to one or more USD primitives. You can use also programmatically assign materials using VEX, programmatically override material settings for each assignment, and programmatically assign materials to geometry subsets.

Attribute Wrangle Create/edit USD primitive attributes using a VEX snippet.

Auto Select LOD Automatically selects a level-of-detail variant based on the primitive’s distance from the camera.

Bake Skinning "Bakes" animation driven by a UsdSkel into transforms and point positions.

Begin Context Options Block This node begins a block of LOP nodes, within which certain context options have certain values.

Blend Partially applies edits to a layer’s attributes based on a fractional weight.

Cache Caches the results of cooking the network at different times, increasing playback speed.

Camera Adds a USD camera to the scene.

Capsule Creates or edits a "capsule" (tube with hemispherical ends) shape primitive.

Collection Creates/edits a collection using selected prims.

Cone Creates or edits a cone shape primitive.

Configure Layer Edits metadata on a layer.

Configure Primitives Edits various metadata on one or more primitives.

Configure Properties Configures metadata on properties (relationships and attributes).

Configure Stage Configures metadata for how to load layers into the stage and asset resolution.

Create LOD Uses the PolyReduce SOP to automatically generate multiple levels of detail from a high-res model, and stores them as USD variants.

Cube Creates or edits a cube shape primitive.

Cylinder Creates or edits a cylinder shape primitive.

Dome Light Creates or edits a USD Dome Light prim. A dome light emits light inward, simulating light coming from the sky/environment surrounding the scene.

Drop Runs a simulation to drop primitives under gravity.

Duplicate Creates copies of a prim (and its descendants).

Edit Interactively transforms prims in the viewer. Can use physics collisions to position props realistically.

Edit Context Options

Edit Material Allows you to edit an existing USD material by modifying parameters and shader connections. This can be useful if the existing material is on a non-editable layer.

Edit Properties Lets you build a spare parameter interface to directly edit attribute and relationship values.

Edit Prototype Switch point instances or USD instanceable prims to instance a different prototype.

Edit Target Layer Allows you to apply edits directly in a lower layer, instead of overriding prims and attributes in the active layer.

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

Extract Instances Converts an instance into a "real" editable prim.

Fetch Grabs the output of another LOP, potentially in another LOP network.

Follow Path Constraint Constrains a prim to follow a path curve.

For Each The end node of a For-Each loop block.

Geometry Subset VOP Creates USD geometry subsets within geometry prims (similar to groups in SOPs) based on evaluating a VEXpression or VOP network.

Graft Takes scene graph trees from other inputs and attaches them onto branches of the scene graph tree in the first input.

Inline USD Parses usda code representing a layer and adds it to the layer stack.

Instancer Instances or copies primitives onto points.

Karma Procedural Sets up render-time instantiation for Karma.

Karma Render Properties Configure Render Properties for Karma (Beta).

Karma Standard Render Vars Create standard karma render vars (AOVs/Image Planes).

LOP nodes LOP nodes generate USD describing characters, props, lighting, and rendering.

Layer Break Starts a new active sublayer that subsequent nodes will edit.

Layer Replace Replaces all uses of a certain layer with a substitute layer from its second input.

Light Creates or edits a USD Light prim. This node also adds some useful Karma-specific attributes.

Light Linker Creates USD light link properties based on rules.

Light Mixer Lets you interactively edit USD properties for multiple lights.

Load Layer

Look At Constraint Constrains a prim to always point toward a target.

Material Library Imports Material VOP nodes as USD material prims.

Material Linker Creates material assignments based on rules.

Material Variation Creates attributes/primvars to override material parameters per-prim/instance.

Merge LOP Merges the layers from incoming stages into a unified layer stack.

Modify Point Instances Modify point transforms and property values for individual point instances.

Null This node does nothing. It can be useful to insert a Null into a network as a "fixed point" in the network that you can refer to by name in expressions/scripts.

Output Represents the output of a subnetwork. Allows you to design a node asset with multiple outputs.

Parent Constraint Makes a primitive appear to inherit the transform hierarchy of another prim somewhere else in the tree.

Points Constraint Position and Orient primitives using point positions from a geometry.

Primitive Bulk-creates one or more attributes of a certain type.

Prune Hides or deactivates primitives and point instances.

Python Script Lets you write Python code in the node to use the USD API to directly manipulate the stage.

Reference References the contents of an external USD file into a branch of the existing scene graph tree, or removes/replaces existing references.

Render Geometry Settings Applies renderer-specific geometry settings to geometry in the scene graph.

Render Product Creates or edits a UsdRenderProduct prim, which represents an output of a renderer (such as a rendered image file or otherfile-like artifact produced by a renderer), with attributes configuring how to generate the product.

Render Settings Creates or edits a UsdRenderSettings prim, which holds the general settings for rendering the scene.

Render Var Specifies a custom variable computed by the renderer and/or shaders, either a shader output or a light path expression (LPE).

Retime Instances Offsets and/or scales the timing of animation on selected instances.

SOP Create Lets you create geometry in a SOP subnetwork inside this node, so you can create geometry in-place in the LOP network instead of needing a separate SOP network.

SOP Import Imports geometry from a SOP network into the USD scene graph.

SOP Modify Converts USD geometry into SOP geometry, runs the SOP subnet inside this node on the geometry, and converts the changes back to USD overrides.

Scene Import Imports models, materials, and lights from the Object level into the LOP network.

Scope Creates a "scope" primitive. Scope is the simplest form of grouping, and does not have a transform. Scopes can be useful for organizing the scene tree.

Set Extents Sets the bounding box metadata of selected primitives.

Set Variant Selects (switches to) one of the variants stored in a variant set on a primitive.

Simulation Proxy Generates low-poly collison geometry suitable for physical simulation and creates a proxy relationship to the original model.

Sphere Creates or edits a sphere shape primitive.

Stage Manager Provides a convenient interface to reference in many files at once and place them in the scene graph tree.

Store Parameter Values Lets you store temporary (unsaved) data in the stage.

Sublayer Imports from USD files or other LOP node chains into as sublayers, or removes/replaces/reorders existing sublayers.

Subnet Encapsulates a LOP subnetwork, allowing you to organize and hide parts of the network.

Surface Constraint Constrain a prim to stick to a surface.

Switch Passes through one of several inputs, based on a parameter choice or expression.

TimeShift Outputs the stage as it is at a different point in the timeline.

Transform Edits the transforms of selected USD primitives.

Transform UV Moves, rotates, and scales texture coordinates on USD primitives.

USD ROP

USD Render ROP

Value Clip

Vary Material Assignment Assign different materials across a number of prims to create variation.

Volume References volume data on disk into a volume prim containing field prims.

Xform Creates or edits an Xform prim. Xform (and its sub-classes) represents a transform in the scene tree.

attribvop


attributes

Attribute VOP ?

Attribute Wrangle Create/edit USD primitive attributes using a VEX snippet.

Edit Properties Lets you build a spare parameter interface to directly edit attribute and relationship values.


cameras

Camera Adds a USD camera to the scene.


collections

Collection Creates/edits a collection using selected prims.


combine

Graft Takes scene graph trees from other inputs and attaches them onto branches of the scene graph tree in the first input.

Merge ?

Overlay ?

Reference References the contents of an external USD file into a branch of the existing scene graph tree, or removes/replaces existing references.

Sublayer Imports from USD files or other LOP node chains into as sublayers, or removes/replaces/reorders existing sublayers.


constraints

Align Constraint ?

Follow Path Constraint Constrains a prim to follow a path curve.

Look At Constraint Constrains a prim to always point toward a target.

Parent Constraint Makes a primitive appear to inherit the transform hierarchy of another prim somewhere else in the tree.

Pin Constraint ?

Points Constraint Position and Orient primitives using point positions from a geometry.

Surface Constraint Constrain a prim to stick to a surface.


context_options

Begin Context Options Block This node begins a block of LOP nodes, within which certain context options have certain values.

Context Options Block ?

Edit Context Options


crowds

Bake Skinning "Bakes" animation driven by a UsdSkel into transforms and point positions.

Vary Material Assignment Assign different materials across a number of prims to create variation.


geometry

Geometry Subset VOP Creates USD geometry subsets within geometry prims (similar to groups in SOPs) based on evaluating a VEXpression or VOP network.

Karma Procedural Sets up render-time instantiation for Karma.

Simulation Proxy Generates low-poly collison geometry suitable for physical simulation and creates a proxy relationship to the original model.

SOP Create Lets you create geometry in a SOP subnetwork inside this node, so you can create geometry in-place in the LOP network instead of needing a separate SOP network.

SOP Modify Converts USD geometry into SOP geometry, runs the SOP subnet inside this node on the geometry, and converts the changes back to USD overrides.

Volume References volume data on disk into a volume prim containing field prims.


import

Fetch Grabs the output of another LOP, potentially in another LOP network.

File ?

Load Layer

Payload ?

Reference References the contents of an external USD file into a branch of the existing scene graph tree, or removes/replaces existing references.

Scene Import Imports models, materials, and lights from the Object level into the LOP network.

Scene Import (All) ?

Scene Import (Cameras) ?

Scene Import (Lights) ?

Scene Import (Materials) ?

SOP Import Imports geometry from a SOP network into the USD scene graph.

Stage Manager Provides a convenient interface to reference in many files at once and place them in the scene graph tree.

Sublayer Imports from USD files or other LOP node chains into as sublayers, or removes/replaces/reorders existing sublayers.


instancing

Copy to Points ?

Edit Prototype Switch point instances or USD instanceable prims to instance a different prototype.

Extract Instances Converts an instance into a "real" editable prim.

Instance to Points ?

Modify Point Instances Modify point transforms and property values for individual point instances.

Point Instancer ?

Retime Instances Offsets and/or scales the timing of animation on selected instances.


lights

Dome Light Creates or edits a USD Dome Light prim. A dome light emits light inward, simulating light coming from the sky/environment surrounding the scene.

Light Creates or edits a USD Light prim. This node also adds some useful Karma-specific attributes.

Light Linker Creates USD light link properties based on rules.

Light Mixer Lets you interactively edit USD properties for multiple lights.


materials

Assign Material Assigns a material to one or more USD primitives. You can use also programmatically assign materials using VEX, programmatically override material settings for each assignment, and programmatically assign materials to geometry subsets.

Edit Material Allows you to edit an existing USD material by modifying parameters and shader connections. This can be useful if the existing material is on a non-editable layer.

Material Library Imports Material VOP nodes as USD material prims.

Material Linker Creates material assignments based on rules.

Material Variation Creates attributes/primvars to override material parameters per-prim/instance.


primitive

Capsule Creates or edits a "capsule" (tube with hemispherical ends) shape primitive.

Circle ?

Cone Creates or edits a cone shape primitive.

Cube Creates or edits a cube shape primitive.

Cylinder Creates or edits a cylinder shape primitive.

Font ?

Grid ?

L-System ?

Platonic Solids ?

Primitive Bulk-creates one or more attributes of a certain type.

Scope Creates a "scope" primitive. Scope is the simplest form of grouping, and does not have a transform. Scopes can be useful for organizing the scene tree.

Sphere Creates or edits a sphere shape primitive.

Torus ?

Trace ?

Xform Creates or edits an Xform prim. Xform (and its sub-classes) represents a transform in the scene tree.


rendering

Additional Render Vars Create multiple render vars.

Karma ?

Karma Render Properties Configure Render Properties for Karma (Beta).

Karma Standard Render Vars Create standard karma render vars (AOVs/Image Planes).

Render Geometry Settings Applies renderer-specific geometry settings to geometry in the scene graph.

Render Product Creates or edits a UsdRenderProduct prim, which represents an output of a renderer (such as a rendered image file or otherfile-like artifact produced by a renderer), with attributes configuring how to generate the product.

Render Settings Creates or edits a UsdRenderSettings prim, which holds the general settings for rendering the scene.

Render Var Specifies a custom variable computed by the renderer and/or shaders, either a shader output or a light path expression (LPE).


test_geometry

Test Geometry: Crag ?

Test Geometry: Pig Head ?

Test Geometry: Rubber Toy ?

Test Geometry: Shader Ball ?

Test Geometry: Squab ?

Test Geometry: Tommy ?


transform

Drop Runs a simulation to drop primitives under gravity.

Edit Interactively transforms prims in the viewer. Can use physics collisions to position props realistically.

Transform Edits the transforms of selected USD primitives.

Transform by SOP Points ?


utility

Blend Partially applies edits to a layer’s attributes based on a fractional weight.

Cache Caches the results of cooking the network at different times, increasing playback speed.

Configure Layer Edits metadata on a layer.

Configure Primitive ?

Configure Property ?

Configure Stage Configures metadata for how to load layers into the stage and asset resolution.

Duplicate Creates copies of a prim (and its descendants).

Edit Target Layer Allows you to apply edits directly in a lower layer, instead of overriding prims and attributes in the active layer.

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

For Each The end node of a For-Each loop block.

Inline USD Parses usda code representing a layer and adds it to the layer stack.

Instancer Instances or copies primitives onto points.

Isolate ?

Layer Break Starts a new active sublayer that subsequent nodes will edit.

Layer Replace Replaces all uses of a certain layer with a substitute layer from its second input.

Null This node does nothing. It can be useful to insert a Null into a network as a "fixed point" in the network that you can refer to by name in expressions/scripts.

Output Represents the output of a subnetwork. Allows you to design a node asset with multiple outputs.

Prune Hides or deactivates primitives and point instances.

Python Script Lets you write Python code in the node to use the USD API to directly manipulate the stage.

Set Extents Sets the bounding box metadata of selected primitives.

Store Parameter Values Lets you store temporary (unsaved) data in the stage.

Subnetwork ?

Switch Passes through one of several inputs, based on a parameter choice or expression.

TimeShift Outputs the stage as it is at a different point in the timeline.

Transform UV Moves, rotates, and scales texture coordinates on USD primitives.

Value Clip


variants

Add Variants to Existing Primitive ?

Add Variants to New Primitive ?

Auto Select LOD Automatically selects a level-of-detail variant based on the primitive’s distance from the camera.

Create LOD Uses the PolyReduce SOP to automatically generate multiple levels of detail from a high-res model, and stores them as USD variants.

Set Variant Selects (switches to) one of the variants stored in a variant set on a primitive.


view

Toggle Stowbars ?