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Since | 19.0 |
Overview ¶
This node is part of the network created by the Component Builder tool. The component builder network gives you a framework in LOPs to create a Component model (usually a prop, such as a chair or tree) and export it to USD for re-use.
This node is either a SOP network the user can use to build the component model from scratch, or an import node to grab the geometry from somewhere else (such as another SOP network or a geometry file).
You can dive inside this node, to a SOP network inside. In this network you can build the component model’s geometry.
To build a component with multiple geometry variants, you can insert a Component Geometry Variants LOP between the initial Component Geometry node and the
Component Material Node. Then you can wire in more Component Geometry nodes representing the variants.
See how to use the component builder tool for more information.
Proxy outputs ¶
The SOP network inside has three output nodes:
-
Green (
default
) output node. This is the “real” geometry of the component. -
You can also optionally generate simplified proxy geometry and connect it to the yellow
proxy
output. This geometry can be used for display in an OpenGL viewer. If you connect this output, the default output is used as therender
purpose.Generating efficient GL proxy geometry can make a big difference in performance. Use the following tips to make fast display proxy geometry:
-
When translating to USD, use as few mesh prims as possible, ideally just one.
-
Triangulate your polygons and remove vertex attributes.
-
Use the
Normal SOP to add a point normal attribute to the geometry, instead of making the GL viewer do it.
-
Divide and Vertex Split nodes may be helpful in creating proxy geometry.
-
-
You can also optionally generate simplified collision geometry and connect it to the pink
simproxy
output. This geometry is used for computing collisions in a simulation, as well as for things such as theEdit node’s “Use Physics” mode or the
Drop node.
Sim proxy geometry is often very simple compared to the render or display geometry.
For example, if you have an apple component, even the low-res “display” proxy will probably be mostly round, have indentations with the top having stem coming out of it, a leaf on the stem, and so on, so you can tell what it represents in the viewer.
The “sim proxy” version of the geometry will almost certainly eliminate the indentations, stem, leaf, small bumps, and so on. It can be just a simple spheroid that approximates the geneeral shape of the original. Depending on how much you value speed vs. accuracy in the simulation, you could use quite a low-poly shape that is more blocky than round.
-
The
PolyReduce SOP is useful for quickly creating a low-res display proxy.
-
The
Convex Decomposition SOP is useful for creating a low-res convex collision proxy.
Parameters ¶
Input Source
The source of this node’s geometry.
Internal SOP network
Use the output(s) of the SOP network inside this node.
File
Use the contents of an external geometry file (or files).
External SOP
Use the output of a SOP node (or nodes) somewhere else in this scene file.
Fix SOP Outputs
When Input Source is Internal SOP network, re-create the three output nodes in the contained SOP network. This can be useful if you accidentally delete one of the output nodes.
Default/Render
When Input Source is File, the path to a file containing the default geometry (if the other fields are filled in, this is the render purpose geometry).
Proxy
When Input Source is File, the path to a file containing the fast display proxy geometry.
SimProxy
When Input Source is File, the path to a file containing the simulation (collision) proxy geometry.
Missing Frame
What to do when a file is missing from an animated sequence: either have no geometry just at that frame, or trigger an error.
Default/Render
When Input Source is External SOP, the node path to the SOP node whose output to use as the default geometry.
Proxy
When Input Source is External SOP, the node path to the SOP node whose output to use as the fast display proxy geometry.
SimProxy
When Input Source is External SOP, the node path to the SOP node whose output to use as the simulation (collision) geometry.
Attributes ¶
Converted Attribs
Geometry attributes to be imported from SOPs as primvars.
Index Attributes
Converted attributes which should be index primvars.
Partition Attributes
Attributes for creating GeomSubsets on meshes.
Prefix Subsets with Attribute Name
When creating subsets from Partition Attributes, the subsets are named by combining the attribute name with the partition attribute’s value (a string or integer). This avoids name collisions when multiple partition attributes contain the same values, but can be undesirable if precise control of the subset names is required. For string attributes, if this option is disabled the attribute values will be directly used as the subset names.
Subset Groups
Primitive groups which will be converted into GeomSubests on meshes.
Translate UV Attribute to ST
Converts the SOP vertex attribute 'uv' into a USD PrimVar called 'primvars:st'.
Topology Attributes
Controls whether USD topology attributes should be authored as time sampled or default values.
Treat Polygons as Subdivision Surfaces
Any polygon meshes not already tagged as subdivs, set the subdivisionScheme to 'catmullClark'.
Compute Extents Hint
Generates extentsHint and extents on missing gprims, xforms, and scopes.
Primitives ¶
Packed Primitives
Configures how packed prims from SOPs should be converted to USD.
Import Height Fields as Mesh
Converts imported height fields to geometry, rather than importing as Field prims.
Advanced ¶
Geo Variant Name
Sets the variant name when this node is connected to a Component Geometry Variant.
Houdini Icon
Optional path to an icon file, or Houdini icon name (for example, SHELF_tree_conifer
). If you set this, Houdini’s Scene Graph Tree pane will display this variant of the component prim using this icon.
Enforce Model Kind Hierarchy
Ensures that no model kind (component, assembly, etc…) is found beneath the component root.
Add GeomModelAPI ¶
Turn this on to set the wireframe color and draw mode.
Custom Data ¶
You can use this multiparm to add custom attributes to the geometry prim created by this node.
See also |