Houdini USD Plugins
The Houdini USD plugin was removed from the USD distribution in version 20.05 in favor of native USD support in Houdini Solaris. This documentation remains here for historical reference.
Configure Environment
There are a couple of prerequisites to using the Houdini plugins.
- Ensure that you built the Houdini plugins, this is enabled in the build with -DPXR_BUILD_HOUDINI_PLUGIN passed as an option to cmake.
- Ensure that the following environment variables are configured. We'll refer to the install location of your USD build with USD_INSTALL_ROOT, this is determined in the build with the cmake flag, -DCMAKE_INSTALL_PREFIX.
| Name | Meaning | Value |
|---|---|---|
HOUDINI_PATH |
This is the search path the Houdini uses to find resources. | USD_INSTALL_ROOT/third_party/houdini:& |
HOUDINI_DSO_ERROR |
Setting this to 1 helps debug issues with loading plugins into Houdini. | 1 |
HOUDINI_DSO_PATH |
Search path Houdini uses to find plugins. It is relative to HOUDINI_PATH. | @/plugin:& |
HOUDINI_SCRIPT_PATH |
Search path the Houdini uses to find python scripts | @/scripts:/USD_INSTALL_ROOT/lib:& |
HOUDINI_PYTHON_LIB |
If you build USD with the python libs that ships with Houdini, you don't need to set this. However if you use a different python build, you need to set this variable so that Houdini runs with the python interpreter you built USD with. | PYTHON_INSTALL/lib/libpython2.7.so |
Houdini treats a few characters specially in configuration variables. See http://www.sidefx.com/docs/houdini/basics/config_env
For more information see our page on Advanced Build Configuration.
The Houdini USD plugins add these nodes.
| USD Import | SOP | Import USD geometry into Houdini |
| USD Output | ROP | Output geometry from Houdini as USD |
| USD Camera | OBJ | Import a camera specification from USD |
| USD Reference | ROP | Add a reference to a USD prim in a USD file |
| USD Sublayer | ROP | Add a sublayer to a USD file |
| USD Coalesce | ROP | Create a USD file that references a sequence of USD files that each contain 1 frame of data |
| USD Unpack | SOP | Unpack USD Packed Prims |
| USD Instance Prototypes | SOP | Add attributes to primitives to enable the USD Output ROP to write USD Point Instancer primitives |
| USD Export Attributes | SOP | Add attributes to primitives to control how the USD Output ROP writes geometry |
| USD Bind Proxy | SOP | Create a USD prim that contains render geometry and proxy geometry |
| USD Retime | SOP | Adjust the timing of a USD Packed Prim |
All of these nodes have help cards. In addition there are a couple more documents.
| A Tour of USD Houdini Primitives | The Usd Import node will create USD Packed Primitives. This document describes these primitives and how to import and unpack them. |
| Writing USD from Houdini | |
| Houdini USD Example Workflow | This document takes you through the process of writing USD overlays from Houdini. |
