Houdini 16.5

HScript commands

HScript is Houdini’s legacy scripting language.

HScript is still available in Houdini for compatibility with older files and scripts. For new scripts, we recommend you use the scripting API instead.

Expansion of a Houdini command follows the C shell expansion standards very closely. HScript commands are generally separated by newlines, however you can put multiple commands on a single line separated by semicolons. Commands are used to control anything to do with ui or node states. For example, to control the state of Houdini, change display flags on nodes, dump nodes as scripts, add/delete/copy/paste operators, add/modify/remove parameters on nodes, etc.

See the HScript language guide for more information about using HScript.

Commands

  • alias

    Creates an alias for a command or sequence of commands.

  • appendseq

    Appends a series of files to the current sequence in mplay.

  • atjob

    Execute commands at a future time.

  • audiopanel

    Changes parameters of the audio pane.

  • autosave

    Enables/disables auto saving.

  • bonealigncapture

    Aligns the capture and animation (deform) regions.

  • boneconvert

    Updates bones from old Houdini 4 hip files.

  • bonefixchops

    Cleans up any references to a bone in InverseKin CHOPs before you delete the bone.

  • bonemoveend

    Adjusts the length and angles of the given bone object so that the bone would end at the given position in the rest chain.

  • bookmark

    Add, list, or remove bookmarks.

  • break

    Breaks out of the current loop.

  • bundlelist

    Allows different options of a bundle list pane to be set.

  • chadd

    Adds channels to the objects specified.

  • chalias

    Create an alias for a channel name.

  • animeditor

    Sets various options of the animation editor.

  • chanlist

    Sets various options of the channel list.

  • chautoscope

    Changes autoscope property of parameters (automatically scope when object is selected).

  • chblockbegin

    Signals the start of a block of chadd/chkey commands in a script file.

  • chblockend

    Signals the end of a block of chadd/chkey commands in a script file.

  • chcommit

    Commits pending key changes.

  • chcp

    Copies the contents of one channel to another.

  • chgadd

    Creates one or more channel groups.

  • chgls

    Lists channel groups.

  • chgop

    Sets the contents of a channel group.

  • chgpopulate

    Populates a channel group with a node’s channels.

  • chgrm

    Removes channel groups

  • chhold

    Puts channels into "hold" or "pending" state.

  • chkey

    Edits or inserts a key.

  • chkeyget

    Samples channels at given times and returns key information.

  • chkeyls

    List key times for channels.

  • chkeymv

    Moves keys in channels to different frames/times

  • chkeyrm

    Removes keys in the specified channels at different frames/times

  • chlock

    Locks parameters so they can’t be modified.

  • chls

    Lists channels.

  • chopexportmap

    Manipulates CHOP export mapping overrides.

  • chopls

    Lists the tracks in a chop operator.

  • chopscope

    Assigns CHOP channels to available viewers by pairing CHOP paths with CHOP channels.

  • chopview

    Sets various CHOP viewer options.

  • chread

    Reads channel data from a file.

  • chrefit

    Refits the channels using cubic interpolation.

  • chrename

    Renames a channel.

  • chreverse

    Reverse the channel data over a given range.

  • chrm

    Removes a channel

  • chround

    Moves or replaces keys so that they lie on integer frame values.

  • chscope

    Sets the channel scope.

  • chstretch

    Stretches out animation on channels.

  • chwrite

    Writes channel data out to a .chan or .bchan file.

  • clear

    Clears the textport.

  • closeport

    Closes a communication port created by the openport command.

  • cmdread

    Runs the commands in a specified file.

  • colladaimport

    Imports a COLLADA (1.4.0) file.

  • colorsettings

    Changes the gamma and/or LUT on various UI gadgets.

  • commandecho

    Enables or disables the echoing of commands.

  • compfree

    Releases all cached data and images in use by all composite networks.

  • compopts

    Controls compositing cache usage and threading.

  • compproject

    Controls the current compositing project.

  • continue

    Skips to the end of a loop iteration.

  • cplane

    Changes construction plane parameters.

  • datatree

    Sets the current plugin used by a data tree pane.

  • desk

    Reconfigures pane layouts.

  • dopdatahint

    Adds hints for DOP networks to validate simulations.

  • dopdatatypealias

    Creates an alias for a DOP data type.

  • dopdatatypes

    Prints a list of available DOP data types.

  • dopsave

    Saves the entire state of a DOP simulation to a file.

  • dopsavedata

    Saves a DOP simulation data item to a file.

  • dopsolveadddata

    Adds data to a DOP object when running a Script Solver DOP.

  • dopsolvecopydata

    Copies some DOP data from one location to another when running a Script Solver DOP.

  • dopsolveremovedata

    Removes data from a DOP object when running a Script Solver DOP.

  • dopsolvesetoption

    Sets a value on a piece of DOP data when running a Script Solver DOP.

  • dsedit

    Built-in alias for otedit.

  • dsoinfo

    Displays paths of plug-in functions and operator types.

  • dsreload

    Reloads all OPs which are based on scripts.

  • echo

    Prints text to the textport.

  • else

    Else conditional for an if statement.

  • end

    Termination of a for or foreach statement.

  • endif

    Termination of the if statement.

  • excat

    Prints expression source code.

  • exedit

    Opens expressions in an editor.

  • exhelp

    Shows usage information for an expression.

  • exit

    Stops execution of the script file. If the optional status code is provided, then it sets the variable 'status' to the given integer.

  • exls

    Lists the current expression functions

  • exread

    Load custom expression source code from external files.

  • exrm

    Removes custom expressions.

  • fbximport

    Imports a Filmbox FBX file.

  • fbximportanim

    Imports a single Filmbox FBX animation curve.

  • fcur

    Gets or sets the current frame number.

  • fdependadd

    Adds a file dependency.

  • fdependhide

    Hides a file dependency.

  • fdependls

    Lists all file dependencies.

  • fdependrm

    Removes a file dependency.

  • filechooser

    Opens a file chooser and prints the chosen file.

  • for

    Loops through a block of commands according to a counter.

  • foreach

    Loops through a block of commands for each item in a list.

  • fplayback

    Sets various options of the playbar.

  • fps

    Gets or sets the current playback speed.

  • frange

    Sets the playback range on the playbar.

  • fset

    Sets the playback range to a certain length

  • ftimecode

    Gets or sets the current frame in timecode format.

  • geocache

    Manipulates the internal geometry cache.

  • glcache

    Manipulates the OpenGL caches.

  • help

    Prints usage help for a command.

  • helpbrowser

    Performs actions related to the help browser pane.

  • history

    Prints the command history.

  • if

    Conditionally executes a block of commands if a condition is true.

  • imgdispopt

    Sets the global image viewer display options.

  • imgsave

    Writes images from a Composite View or MPlay to disk

  • imgview

    Changes global options of a COP/Mplay image viewer.

  • imgview2d

    Changes options of a 2D view of a COP image viewer.

  • imgviewhist

    Changes options of a Histogram view of a COP image viewer.

  • imgviewls

    Prints the names of available COP/Mplay image viewers to use with imgview.

  • imgviewtime

    Changes options of a Timeline view of a COP image viewer.

  • imgviewtool

    Invokes a tool in a COP image viewer (or lists available tools).

  • iprview

    Sets various options of an IPR view pane.

  • java

    Starts a java virtual machine.

  • job

    Get or set the $JOB variable.

  • kinconvert

    Updates old hip files to new IK structure.

  • linker

    Sets various options of the light linker.

  • listchooser

    Presents a graphical interface to the user to choose from a list of options.

  • loadaudio

    Load, unload, and set options for audio.

  • loadseq

    Loads a sequence of files into mplay.

  • matrman

    Generate a RenderMan sl file from a shader.

  • matupdateref

    Updates all the Palette material references.

  • memory

    Prints current memory usage.

  • menurefresh

    Reloads the contents of the OPmenu.xml, PARMmenu.xml, ParmGearMenu.xml and CHGmenu.xml menu files.

  • message

    Presents text to the user.

  • mnew

    Resets the session.

  • mplayfit

    Fits the mplay window to the image (at 100%).

  • mplayhome

    Fits mplay image to the viewport size.

  • mplayprofile

    Sets the current mplay profile.

  • mread

    Loads a hip file.

  • mwrite

    Save the current session to a hip file.

  • nbadd

    Create network boxes

  • nbcolor

    Color network boxes

  • nbcp

    Copy network boxes

  • nbget

    Get network box flag information

  • nbglob

    Pattern expansion for network box names

  • nblocate

    Locate and move network boxes

  • nbls

    List network boxes

  • nblsop

    Lists operators contained in network boxes

  • nbname

    Renames a network box

  • nbop

    Sets the contents of a network box.

  • nbrm

    Deletes network boxes

  • nbset

    Set network box flags.

  • nbsize

    Resizes network boxes

  • netcolumns

    Sets the visible columns in the network editor’s list mode.

  • neteditor

    This command is no longer used.

  • netviewdep

    This command is no longer used.

  • networkeditor

    Sets various options of the network editor.

  • nextkey

    Moves playback to the next or previous key.

  • nodegraph

    This command is no longer used.

  • objcache

    Manipulates the internal object transformation cache.

  • objcleantransform

    Zeroes transforms on an object.

  • objextractpretransform

    Transfers an object’s pre-transform values to its local transforms.

  • objkinoverride

    Sets the kinematic override option.

  • objlightlink

    Manages object light category selection in a light-centric way.

  • objmaterial

    Manages object-local overrides of material parameters.

  • objparent

    Controls the "keep position when parenting" option.

  • objpretransform

    Sets or displays an object’s pre-transform matrix.

  • objresetpretransform

    Resets the given object’s pre-transform values to the identity matrix.

  • ombind

    Binds a handle to an operator parameter.

  • ombindinfo

    Lists parameters bound to an operator’s handle.

  • omls

    Lists the available handles for an operator type.

  • omparm

    Changes a handle’s settings.

  • omsbind

    Binds an operator parameter to a selector

  • omsbindinfo

    Lists the selectors bound to an operator.

  • omsls

    Lists the available selectors for an operator type.

  • omsunbind

    Removes bindings between operators and selectors.

  • omswhere

    Lists the operators bound to a selector.

  • omunbind

    Removes bindings between an operator and a handle.

  • omwhere

    Lists the operators bound to a handle.

  • omwrite

    Writes out all handle and selector bindings to a file.

  • opadd

    Adds an operator to the network.

  • opalias

    Allows an operator type to be created using an alternate name.

  • opautoplace

    Autoplaces a node tile within a network.

  • opbadd

    Creates operator bundles.

  • opbfilters

    Lists all valid filters for bundles.

  • opbls

    Lists bundles.

  • opbname

    Renames a bundle.

  • opbop

    Modifies operator bundles.

  • opbrm

    Removes operator bundles.

  • opcf

    Changes to a different folder in the operator hierarchy.

  • opchange

    Search and replace text in parameter values.

  • opchangetype

    Changes an operator to a new type.

  • opchmod

    Changes the access permissions of operators.

  • opcollapse

    Collapses nodes into a subnetwork.

  • opcolor

    Gets or sets an operator’s tile color in the network editor.

  • opcomment

    Gets or sets a comment string for an operator.

  • opcook

    Tells (or forces) an object to re-cook.

  • opcopy

    Copies an operator and its dependencies to the clipboard.

  • opcp

    Copies an operator to a new place in the operator hierarchy.

  • opdefaultcolor

    Changes the initial color of a node when it is put down.

  • opdefaultshape

    Changes the initial shape of a node when it is put down.

  • opdelscript

    Gets or sets a script to run when an operator is deleted.

  • opdepend

    Lists all operator dependencies of a node.

  • opdeprecate

    Marks node types as deprecated and hides them from the tab menu.

  • openport

    Opens a communication port to Houdini.

  • opeventscriptcache

    Manipulates the internal event script path cache used to avoid excessive searching of the HOUDINI_SCRIPT_PATH.

  • opexclude

    Deletes operator types from the current Houdini session.

  • opexprlanguage

    Gets or sets the default expression language for the specified nodes.

  • opextern

    Shows all/missing external references in a node.

  • opextract

    Expands a subnetwork

  • opfind

    Find operators that match a set of criteria.

  • opfirstname

    Changes the initial name of a node when it is put down.

  • opgadd

    Creates a new operator group.

  • opget

    Gets operator properties.

  • opgetinput

    Gets the node attached to a certain input of an operator.

  • opglob

    Expands a pattern into a list of operator names.

  • opgls

    Lists operator groups.

  • opgop

    Controls membership of operator groups

  • opgrm

    Removes an operator group from the current network.

  • ophelp

    Displays help for an operator or operator type.

  • ophide

    Hides nodes from the tab menu.

  • opinfo

    Displays information about the operator, including the comment.

  • oplayout

    Automatically lays out operators in the network editor.

  • oplegacyinputs

    Specifies input names for legacy nodes that were saved only with input numbers.

  • oplocate

    Gets/sets the X/Y coordinates of operator tiles in the network view.

  • opls

    Lists operators in the network hierarchy.

  • opmenu

    Shows the items of a menu parameter on an operator.

  • opmultiparm

    Gets or sets multiparm channel linking information for a node.

  • opname

    Renames an operator.

  • oporder

    Changes the user-defined order of operators.

  • oppane

    Show an editor for an operator.

  • opparm

    Gets/sets/manipulates parameters on a node.

  • oppaste

    Paste data copied with opcopy into a network.

  • oppresetload

    Loads channels and parameter values into an operator from a preset.

  • oppresetloadfile

    Loads channels and parameter values into an operator from a .preset file.

  • oppresetls

    Lists the presets available for an operator.

  • oppresetrm

    Removes a preset.

  • oppresetsave

    Saves channels and parameter values from an operator as a preset.

  • oppresetsavefile

    Saves channels and parameter values from an operator to a .preset file.

  • opproperty

    Creates spare properties from a set of pre-defined properties

  • oppwf

    Prints the current folder in the network hierarchy.

  • opramp

    Sets a key in an operator’s ramp.

  • opread

    Loads an operators file created with opwrite.

  • oprename

    Changes the name that appears on toolbars to represent an operator type.

  • oprm

    Deletes operators.

  • oprmtype

    Deletes operators of a specific type.

  • opsave

    Saves the output data of an operator to a file.

  • opscale

    Obsolete. Use neteditor -v instead.

  • opscript

    Prints the commands necessary to recreate an operator.

  • opset

    Turns various operator flags on or off.

  • opspare

    Add, remove or list spare parameters in an operator.

  • opspareds

    Sets the dialog script describing spare parameters on one or more nodes.

  • opstat

    Print node creation time, modification time, author, and permissions.

  • optype

    Prints type-specific information about operators.

  • optypeinstall

    Built-in alias for optyperead

  • optyperead

    Loads an .optype archive and installs the contained type into a Houdini directory.

  • optypeuninstall

    Removes all references to an operator.

  • opunhide

    Makes operators accessible in the toolbars.

  • opunload

    Causes a node to throw away any cached geometry.

  • opunwire

    Disconnects inputs from an operator.

  • opupdate

    Re-cooks operators if their referenced files have changed.

  • opuserdata

    Provides access to name/value pair data that can be set on a node.

  • opwire

    Connects the output of one operator to the input of another.

  • opwrite

    Saves operators to a file.

  • otcollapse

    Create an operator type library from separate files.

  • otcomment

    Gets/sets the comment text associated with an operator type.

  • otconfig

    Sets various options of the operator type manager.

  • otcontentadd

    Adds a file to an existing operator type definition.

  • otcontentdelete

    Removes data from an operator type definiton.

  • otcontentls

    Lists all sections in an operator type definition.

  • otcontentsave

    Extracts a file from inside an operator type definition.

  • otcopy

    Copies data from inside one HDA file to another.

  • otcreatecompiledtypefrom

    Creates a new operator type definition from a subnet.

  • otcreatetypefrom

    Creates a new operator type definition from a subnet.

  • otdelete

    Deletes operator definitions from an operator type library.

  • otedit

    Opens a property editor for an operator type.

  • otexpand

    Splits an operator type library into component files.

  • otgetotl

    Determines whether/where an operator type is defined.

  • otglob

    Lists operator types matching a pattern.

  • otinuse

    Helps determine what Operator Type Libraries are in a given Hip file.

  • otload

    Loads an operator type library into the current session.

  • otls

    Lists operator types defined in a library file.

  • otmerge

    Copies all operator type definitions from one library file to another.

  • otprefer

    Get/set which type definition to use when multiple implementations are available.

  • otrefresh

    Reloads an operator type library from disk.

  • otrenamesource

    Gives a descriptive name to a library source.

  • otsync

    Syncs the contents of nodes with the contents of their type definitions.

  • ottouch

    Sets the last modified time for an operator type definition.

  • otunload

    Unloads an operator type library.

  • otunsync

    Built in alias for otsync -u.

  • otversion

    Gets/sets the version of an operator type definition.

  • otwrite

    Saves an operator type into an operator type library file.

  • pane

    Creates, closes, or sets options on a pane.

  • panepath

    Sets the current node of all panes in a desk.

  • parmeditor

    Sets various options of a parameter editor.

  • parmlist

    Sets various options of the parameter list within a channel list gadget.

  • parmsheet

    Sets various options of the parameter spreadsheet.

  • pathmap

    Interface to modify or test the HOUDINI_PATHMAP variable.

  • perfmon

    Enable output from the performance monitor.

  • performance

    Set various options of the performance monitor.

  • pilist

    Sets various options of a handle list.

  • play

    Controls playback.

  • pomadd

    Creates a new persistent handle or group.

  • pomattach

    Attaches an operator to a handle, or a handle to a group.

  • pomclear

    Detaches all operators from a persistent handle, or clears a group.

  • pomdetach

    Detaches an operator from a persistent handle, or a handle from a group.

  • pomls

    Lists persistent handles or handle groups.

  • pomparm

    Changes settings of a handle.

  • pomremove

    Delete a persistent handle or handle group.

  • pomrename

    Renames a persistent handle or handle group.

  • pomscript

    Prints the commands to create a persistent handle or group.

  • pomset

    Sets the display flags of a persistent handle or group.

  • preference

    Gets/sets the general preference option values.

  • prependseq

    Inserts files before the current sequence.

  • prompt

    Change the textport prompt string.

  • propertyedit

    Built-in alias for otedit

  • python

    Execute Python statements.

  • pythonpanel

    Performs actions related to the Python panel pane.

  • quit

    Exits Houdini.

  • radial

    Controls radial settings.

  • read

    Reads a line on user input into one or more variables.

  • render

    Cause an output driver (ROP node) to render.

  • rexport

    Edits exprot variables for a network render.

  • rkill

    Stop or pause/unpause a render.

  • ropview

    Sets various options of an Outputs viewer pane.

  • rps

    Lists background render processes.

  • seqls

    Lists the sequences currently loaded in Mplay.

  • set

    Sets a local variable.

  • setcomp

    Set the color components to display.

  • setenv

    Sets a global variable.

  • setplane

    Sets the current plane.

  • shelfdock

    Adds shelves to and removes shelves from the shelf area (dock).

  • shift

    Shifts the contents of the command line argument variables.

  • shopconvert

    Converts RenderMan shaders to native.

  • shoppromote

    Automatically promotes all parameters from a material’s contained shaders onto the material.

  • shopthumb

    Generates a thumbnail image (shader ball) for a material.

  • shopvisible

    Show or hide shaders based on the renderer.

  • sopcache

    Manipulates the internal surface node cache.

  • sopcreateedit

    Create an Edit SOP from the differences between two SOPs.

  • source

    Executes the script commands in a file.

  • stampdirty

    Dirty nodes dependent on a stamping variable..

  • system

    Starts a host system command.

  • takeadd

    Creates a new take.

  • takeautomode

    Sets the take auto-include mode.

  • takeinclude

    Includes parameters in or removes parameters from the current take.

  • takelist

    Sets various options of the take list pane.

  • takeload

    Loads take information from a file saved with the takesave command.

  • takels

    Prints the names of existing takes.

  • takemerge

    Merges included parameters from one or more source takes into a destination take.

  • takemove

    Moves a take under a new parent.

  • takename

    Rename a take, set the label of a take, or change the default basename for new takes.

  • takerm

    Removes one or more takes.

  • takesave

    Saves take information to a file, or prints it to the textport.

  • takescript

    Prints the commands necessary to recreate a take.

  • takeset

    Switches to a different take.

  • tcur

    Gets or sets the current time.

  • test_access

    On Windows, tests the permission of a file path.

  • texcache

    Manipulates the internal texture cache.

  • time

    Print the time taken to execute a command.

  • timeslice

    Sets timeslice options for timesliced channel operators.

  • tmgadd

    Creates time groups.

  • tmgls

    Lists time groups.

  • tmgname

    Renames a time group.

  • tmgop

    Set, add to, or delete the contents of a time group.

  • tmgrm

    Deletes a time group.

  • tmgshift

    Shift a time group by a length of time or number of frames.

  • toolbar

    Creates, edits, or removes a toolbar.

  • treechooser

    Presents a graphical interface to the user to choose from a list of options.

  • treecontrol

    Sets various options of the tree contrl.

  • tset

    Gets/sets the global animation range.

  • ucd

    Change the UNIX working directory.

  • uls

    Returns a list of files and directories in the UNIX working directory. This command is non-recursive.

  • umkdir

    Creates a new directory, dir_name, in the file system.

  • undoctrl

    Turns undo on or off, or clears undo memory.

  • unitlength

    Controls the Houdini Unit Length option.

  • unitmass

    Controls the Houdini Unit Mass option.

  • unix

    Starts a host system command.

  • updateui

    Waits for Houdini’s UI to update.

  • upwd

    Prints the Unix working directory.

  • urm

    Unlinks file_name, in the file system. This method cannot unlink directories.

  • varchange

    Cooks any operators using changed variables.

  • version

    Prints the application’s version.

  • vexinfo

    Lists the currenly loaded VEX functions.

  • vexprofile

    Turns profiling of VEX functions on/off

  • viewagentopts

    Set various crowd agent display options for a viewport.

  • viewbackground

    Sets general options for the viewport background.

  • viewcamera

    Make a viewport look through a camera.

  • viewcolor

    Set the color override attribute in a particular viewport.

  • viewcopy

    Copies settings from one viewport or view-memory to another.

  • viewdisplay

    Set various options of a viewport or view-memory.

  • viewdispopts

    Set various options of a viewport.

  • viewdispset

    Set various options of a viewport. Replaces viewdisplay.

  • vieweffect

    Controls viewport settings.

  • viewergrouplist

    Set group list options of viewer panes.

  • viewerinspect

    Gets/sets inspection options for a viewer.

  • vieweroption

    Sets various options for viewer panes.

  • viewerstow

    Stows or unstows components of a viewer.

  • viewhome

    This command allows you to home the named viewports.

  • viewinfotext

    Set info text options for a viewport.

  • viewlayout

    Rearranges viewports in a viewer pane.

  • viewlight

    Controls viewport settings.

  • viewls

    Lists all viewer panes.

  • viewmaskoverlay

    Sets various options of the view mask overlay in viewports.

  • viewname

    Renames a viewport

  • viewonionskin

    Set various onion skinning display options for a viewport.

  • viewoptadd

    Adds display options to all viewers.

  • viewoptenable

    Enable/disable user options in a particular viewport.

  • viewoptls

    Lists options available in viewers.

  • viewoptname

    Renames a display option.

  • viewoptrm

    Removes display options from all viewers.

  • viewoptset

    Gets/sets the settings for a particular display option. These settings are shared by all viewers.

  • vieworthogrid

    Controls display of the grid in an orthographic viewport.

  • viewprojection

    Sets the projection method of a perspective viewport.

  • viewrefplane

    Changes reference plane parameters.

  • viewroto

    Sets image and position options for the viewport background.

  • viewsnapshot

    Manages the view snapshot memory.

  • viewsnapshotoption

    Sets the options for the view snapshot memory.

  • viewtool

    Sets the current tool in a scene viewer (or lists available tools).

  • viewtransform

    Gets/sets projection data for a viewport.

  • viewtype

    Changes the type of a viewport.

  • viewupdate

    Controls the updating of views.

  • viewuvgrid

    Sets various options of the grid in UV texture viewports.

  • viewwrite

    Creates a flipbook from a viewport.

  • vopforcecompile

    Forces a VOP Network to compile its code.

  • vopwritevfl

    Writes code generated from a VOP network to a file.

  • while

    Loops through a block of commands while a condition is true.

Houdini 16.5

Getting started

Using Houdini

  • Geometry

    How Houdini represents geometry and how to create and edit it.

  • Copying and instancing

    How to use copies (real geometry) and instances (loaded or created at render time).

  • Animation

    How to create and keyframe animation in Houdini.

  • Character

    How to rig and animate characters in Houdini.

  • Rendering

    How to render images and animation from the 3D scene.

  • Materials

    How to assign materials and create custom materials for shading.

  • Compositing

    Houdini’s compositing networks let you create and manipulate images such as renders.

  • Digital assets

    Digital assets let you create reusable nodes and tools from existing networks.

  • Import and export

    How to get scene, object, and other data in and out of Houdini.

  • MPlay viewer

    Using Houdini’s stand-alone image viewer.

Dynamics

  • Particles

    How to create particle simulations.

  • Dynamics

    How to use Houdini’s dynamics networks to create simulations.

  • Pyro

    How to simulate smoke, fire, and explosions.

  • Fluids

    How to set up fluid and ocean simulations.

  • Grains

    How to simulate grainy materials (such as sand).

  • Crowd simulations

    How to create and simulate crowds of characters in Houdini.

  • Hair and Fur

    How to create, style, and add dynamics to hair and fur.

  • Finite Elements

    How to create and simulate deformable objects

  • Cloth

    How to create and simulate cloth and other flexible materials.

Nodes

  • Object nodes

    Object nodes represent objects in the scene, such as character parts, geometry objects, lights, cameras, and so on.

  • Geometry nodes

    Geometry nodes live inside Geo objects and generate geometry.

  • Dynamics nodes

    Dynamics nodes set up the conditions and rules for dynamics simulations.

  • VOP nodes

  • Render nodes

    Render nodes either render the scene or set up render dependency networks.

  • Channel nodes

    Channel nodes create, filter, and manipulate channel data.

  • Compositing nodes

    Composite nodes create, filter, and manipulate image data.

Reference

  • Menus

    Explains each of the items in the main menus.

  • Viewers

    Viewer pane types.

  • Panes

    Documents the options in various panes.

  • Windows

    Documents the options in various user interface windows.

  • Stand-alone utilities

    Houdini includes a large number of useful command-line utility programs.

  • Python Scripting

    How to script Houdini using Python and the Houdini Object Model.

  • Expression functions

    Expression functions let you compute the value of parameters.

  • HScript commands

    HScript is Houdini’s legacy scripting language.

  • VEX

    VEX is a high-performance expression language used in many places in Houdini, such as writing shaders.

  • Properties

    Properties let you set up flexible and powerful hierarchies of rendering, shading, lighting, and camera parameters.

  • Python Panels

    You can script custom pane types using Python to create your own UIs.

  • Galleries

    Pre-made materials included with Houdini.