Intro to Houdini

  • Houdini, a procedure oriented 2D,3D graphic application, with built-in package for a lot of simulation operation.

Concept inside Houdini

  • it is all about asset, anything is a asset, (tool, shelf, node, parameter)
OTL Operator Type Libraries
hda houdini digital asset, file format for asset library which contain lots of assets (Channel Editor, Motion View)
IDO Internally Defined Operator, built node asset type in houdini
Chop (#vop) channel operation, basically a attribute driving network of nodes
ChopNet
Cop2
CopNet
Dop
Driver
Object
Particle
Pop
Shop
Sop
Vop
VopNet
VEX builder operatpr

Setting and Configuration

  • env file for environment setting
    HOUDINI_PATH = "$HOUDINI_PATH;X:/myPath/houdini/HFS/16;&"
    HOUDINI_OTLSCAN_PATH = "$HOUDINI_OTLSCAN_PATH;X:/myPath/houdini/HDA_Libs/otls;&"
    HOUDINI_TOOLBAR_PATH="$HOUDINI_TOOLBAR_PATH;X:/myPath/houdini/ToolBar/16;&"
  • start houdini with init script (optionally in full path)
    houdinifx.exe X:\myPath\123.py
  • houdini start will run 123.py, new session will run 456.py, it will always run pythonrc.py in its search path.
  • houdini python path environment variable “HOUDINI_PATH”
  • Houdini project env variables
$HFS/houdini, $HH houdini environment
$HSITE store shared houdini resource
$JOB current work job directory
$HIP readonly houdini internal scene variable, last saved path
  • list all configuration of houdini in Shell:
    hconfig -ap

Tutorial

Houdini GUI Tool Develop

  • Houdini is same node concept as Nuke when access objects in application, based on a root node “hou” to access object under it,
  • in Maya.cmds, you are calling Maya to return the data of the object by object string name instead of the object itself
    • while OpenMaya api and PyMel in Maya is more like same node concept