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Houdini uses environment variables for various purposes, such as
defining paths (sets of directories in which Houdini looks for
certain types of files), commonly used directories (such as
$HFS, the install location of Houdini) and for obscure or highly
Browsing environment variables
hconfig utility displays the meaning or current value of all
Houdini-related environment variables.
hconfig to be available on the command line, you should
set up a Houdini shell environment.
Choose Start ▸ All Programs ▸ Side Effects Software ▸ Houdini X.X.XXX ▸ Command Line Tools.
/Applications/Houdini/HoudiniX.X.XXX/Utilities and double-click
cd to the Houdini install directory and type
source houdini_setup.bash depending on your shell.
Get help on using
Print the current values of common Houdini environment variables
Print the current values of all Houdini environment variables
Print the help for a certain variable
hconfig -h VAR_NAME
hconfig -h HSCRIPT_NO_HISTORY
Print the help for all Houdini environment variables
Setting environment variables
Houdini picks up the system’s environment variables (such as $HOME) as well as the environment variables of the shell from which it was started, on platforms that support those concepts.
Each user’s home Houdini directory can contain a
houdini.env file you can use to specify
environment variables. You may also use the package mechanism for setting environment variables.
houdini.env file doesn’t already exist, Houdini creates a template
houdini.env file with helpful comments when you run Houdini.)
The file should contain one environment variable definition per line. For example:
# Assign BAR to FOO FOO = BAR # Spaces are optional FOO=BAR # Quote values that contain spaces FOO = "BAR BAZ" # Environment variables on the right side # are expanded FOO = $HOME/some/path # Escape $ to avoid expansion of variables FOO = \$HOME/some/path # To unset a default... FOO =
On the Mac, when you launch Houdini from the dock or by double-clicking its icon, it inherits a very minimal environment, and it’s difficult to add variables to it. Use the
houdini.env file (see above) to configure environment variables on the Mac.
(If you start Houdini by typing
houdini in a
Houdini Shell.terminal window, Houdini will inherit the shell’s environment.)
On Windows, right-click My Computer and choose Properties, click the Advanced tab, then click Environment Variables.
You can also use the
set name=value command in the command shell, for example
set UT_INTERRUPT_THRESH=50 sets the Interrupt Cook dialog delay to 5 seconds for any instance of Houdini subsequently started from that shell.
On Linux, the procedure for setting environment variables varies from shell to shell. Check your shell’s man page for details.
In bash use
In csh and tcsh, use
setenv name value.
export UT_INTERRUPT_THRESH=50 sets the Interrupt Cook dialog delay to 5 seconds for any instance of Houdini subsequently started from that shell.
Special characters in path variables
Typically expands to the directories on the HOUDINI_PATH. So, if the HOUDINI_PATH is…
$HIP $HFS/houdini $HOME/houdiniX.Y
… then the value
$HIP/vex $HFS/houdini/vex $HOME/houdiniX.Y/vex
The “default” path for the given variable. For example, to add a directory
For VEX-related variables, expands to the shader type (e.g. Surface, Displacement, Sop, etc.). For example, if