Table of Contents

• What's new
  • Change logs
    • Version log
    • Compatibility log
  • Key features of Houdini 8
  • What's new: Effects
  • What's new: Rendering
  • What's new: Lights and cameras
  • What's new: Character animation
  • What's new: User interface
  • What's new: Modeling
  • What's New: Compositing and image viewing
  • What's new: Shader building
  • What's new: Digital assets
  • What's new: Expressions
  • What's new: HScript
  • What's new: Licensing
  • What was new
    • Version 7.0
      • General
      • Digital assets
      • Modeling
      • Animation and characters
      • Rendering
      • Compositing
      • Effects
      • Commands and expressions
      • Miscellaneous
• Getting started with Houdini
  • The Houdini Family
  • Tutorials
    • Quick start
      • Lesson 1: Quickstart: Modeling
        • Part 1: Modeling the Rocket Fuselage
        • Part 2: Create and Shape the Rocket Fuselage
        • Part 3: Model the Rocket Fins
        • Part 4: Copy the Fins
        • Part 5: Creating a Moonscape
      • Lesson 2: Quickstart: Shading
        • Part 1: Arranging the Objects
        • Part 2: Add a Shader to the Moonscape
        • Part 3: Add Shaders to the Rocket
        • Part 4: Create a Sky Dome
      • Lesson 3: Animating the Rocket
        • Part 1: Setting Keyframes on the Rocket
        • Part 2: Part Two: Adding Squash and Stretch to the Rocket
        • Part 3: Create a Digital Asset
      • Lesson 4: Particles
        • Part 1: Particle Thruster
        • Part 2: Create Particle Network
        • Part 3: Create Vex Smoke shader
        • Part 4: Final animation
    • Animation
      • General Workflow
        • Flipbook
        • Keyframing Techniques
      • Animation Tutorials
        • Lesson 1: Path Animation
    • Character Animation
      • Kinematics
        • Posing a Character
          • Part 1: Pose a Digital Asset Character
        • Bones
        • Editing Bones
        • FK/IK Blending
        • The Rest Angle
        • Follow Curve
        • Dynamic Parenting
          • Part 1: How to Pick up and Put down Objects
          • Part 2: How to Toss Objects: Method One
          • Part 3: How to Toss Objects: Method Two
      • Capturing Geometry
        • Capturing a Simple Arm
        • Attribute Transfer
          • Part 1: Transferring Capture Attributes
          • Part 2: Transferring Attributes from a Metaball
      • Character Deformations
        • Wire Deformations
        • Muscle Deformation with Inflate
    • Houdini Digital Assets
      • Understanding Digital Assets
        • When to use Digital Assets
        • Anatomy of a Digital Asset
        • How Digital Assets work
      • Creating Digital Assets
        • Digital Asset Preparation
        • Defining the Digital Asset
        • Type Properties
        • The Operator Type Manager
      • Editing Digital Assets
        • Locked and Unlocked Assets
        • Operator Type Properties
        • Adding Scripts
      • Building Digital Asset Controls
        • Promoting Parameters
        • Promoting Handles
        • Working with Digital Assets
          • Part 1: Installing a Digital Asset
        • Creating an Object-Level Asset
          • Part 1: Create the Subnetwork
          • Part 2: Create the Operator Type
          • Part 3: Create High Level Parameters
          • Part 4: Test the Asset
          • Part 5: Part Five: Refine the Asset's User Interface
          • Part 6: Part Six: Write Help
          • Part 7: Conclusion
    • Effects
      • Particle Motion
        • Create a Particle Shockwave
        • Particle Sliding
      • Particle Rendering
        • Transferring Attributes
          • Part 1: Transfer color particles
          • Part 2: Transfer after collision
          • Part 3: Assign a Shader to the Particles
          • Part 4: Shade and Render
          • Part 5: Transfer Scale Attributes
        • Wispy Smoke
          • Part 1: Create the Particle System
          • Part 2: Create Geometry from Particles
          • Part 3: Apply Shaders to Geometry
          • Part 4: Add more Attractors to the Simulation
          • Part 5: Animate the Particle System
        • Volumetric Effects
          • Part 1: Creating reference geometry
          • Part 2: Generate 3D texture from metaballs
          • Part 3: Rendering the 3D texture
          • Part 4: Adjusting shader values
    • Lights
      • Create a Light
      • Light Types
        • Area Lights
      • Global Illumination
        • Irradiance
        • Caustics
      • Lighting Tutorials
        • Lesson 1: Environment Illumination
          • Part 1: Background Illumination
          • Part 2: Image-based Illumination
    • Modeling
      • Modeling Techniques
        • Editing Points on a Surface
      • Polygonal Modeling
        • Lesson 1: Beveling a Polygonal Cube
        • Lesson 2: Beveling Facial Features
        • Lesson 3: Creating a Subdivide Cage
        • Lesson 4: Create a Copy Stamp
          • Part 1: Create a star shape
          • Part 2: Copy the stars using stamping
          • Part 3: Add detail to the template geometry
          • Part 4: Conclusion
      • UV Textures
        • Unwrapping with UV Pelt
          • Part 1: Basic Pelting
          • Part 2: Painting Spring Tension
          • Part 3: Adding a Pelting Frame
        • Lesson 1: UV Brush
    • Rendering
      • General Techniques
        • Rendering Image Sequences
        • Test Rendering
      • Mantra
        • Deep Rasters
        • High Dynamic Range Images
    • Shading
      • Shaders
        • Applying Shaders
      • VEX
        • Creating a Color Shader
        • Create a Procedural Shader
          • Part 1: Prepare the Basic Network
          • Part 2: Adding Detail
          • Part 3: Smoothing the snail's belly
• Houdini basics
  • Quick reference
    • General interface
    • Selection
    • Operators
    • Parameters
    • Manipulators
    • Panes
    • Context menus
    • Viewing the scene
    • Display
    • Viewports
    • Mantra quality levels
  • View the scene
    • Tumble, track, and dolly the view
    • Split a viewer pane into multiple viewports
    • Put an image in the background of the 3D viewer
    • Bookmark and recall views
    • Control the display of geometry
    • View one/View all when modeling
    • Speed up drawing and tumbling
    • Edit the grid
  • Desks and panes
    • Work with panes
    • Pane controls
    • Pane types
    • Work with toolbars
    • Link panes together
    • Use desks to switch between different pane configurations
  • Manipulate the network
    • Network types
    • Navigate through the network
    • Encapsulate nodes inside subnetworks
    • Node and parameter paths
    • Cooking
    • View nodes in the network editor
    • Troubleshooting networks and cooking
  • Operators
    • Choose operators/tools with the tab menu
    • Use an operator/tool
    • Node flags
    • Connect (wire up) nodes in the network editor
    • Control the order of inputs
    • Select and manipulate nodes
    • Lock a node to improve efficiency
  • Parameters
    • Edit a node's parameters
    • Edit parameter values
    • Use parameters that reference other nodes
    • Edit color parameters
    • Edit parameters of multiple selected nodes
    • Control the value of a parameter with an expression.
    • Lock and unlock parameters
    • Drive one parameter with the value of another
    • Put parameter controls in the viewport (HUD sliders)
    • Presets and defaults
    • Create custom interface panels to control parameters
    • Copy and paste parameter values
    • Auto scope parameters
    • Use Spare Parameters
  • Manipulators
    • Show the manipulator for a node in the viewer
    • Use the transform manipulators
    • Use the camera and light manipulators
    • Work with persistent manipulators
    • Manage groups of manipulators
    • Use gimbal handles and fix gimbal lock
    • Composite operation handles
    • Snap to features in the compositing viewer
  • Select objects and geometry
    • Select geometry
    • Grow the selection
    • Secure selection
    • Select edges
    • Troubleshooting selection
  • Use the online help
    • Search
    • Help preferences
    • Online help tips and tricks
  • Configure Houdini
    • Edit the main preferences
    • Common view configuration tasks
    • Common network editor configuration tasks
    • Create and edit toolbars
    • Configure hotkeys
    • Customize the Houdini UI and workflow
    • Paths and locations
    • Change the initial objects created when Houdini starts up
• Digital assets
  • About digital assets
    • When to use digital assets
    • Anatomy of a digital asset
    • How digital assets work
  • Create a digital asset
  • Lock, unlock, and edit digital assets
  • Prevent users from being able to edit asset definitions
  • Create a user interface for an asset
    • Create or promote parameters for an asset
    • Promote manipulators up to the asset
    • Write help for an asset
  • Load (install) an asset from an operator type library
  • Operator type libraries (OTLs)
  • Manage digital assets and asset versions
  • Allow users to safely edit assets in a take
  • Edit the contents of an OTL (advanced)
  • Script digital assets
  • Naming operator types
  • OTL tips and tricks
• Organization and workflow
  • Create variations with takes
  • Arrange and organize network nodes
    • Set the color of an operator tile
    • Organize nodes with bundles
    • Organize operators with groups
    • Group tiles visually with network boxes
    • Hide and show node tiles in the network editor
    • Rename multiple nodes at once
• Modeling
  • Objects (OBJ) and Geometry (SOPs)
  • Points and vertices
  • Objects
    • Common object parameters
    • Make one object the parent of another
    • Edit an object's origin/pivot
    • Set an object's pre-transform
    • Create, edit, and use Null objects
    • Create lightweight copies (instances) of objects
    • Rivet one object to another object
  • Modeling node flags
  • Attributes
  • Modeling tools
    • Snapping
    • Object and geometry context menus
    • Construction plane
    • Use geometry as a template
    • Align objects
  • Create geometry
    • Create a modeling object to contain geometry
    • Draw a curve
    • Create an oriented path curve
    • Sweep out a surface by revolving a curve
    • Create a NURBS surface from a curve network
    • Stamp copies of geometry
    • Match geometry to a reference image (rotoscoping)
  • Edit and reshape curves and surfaces
    • Transform objects and geometry
    • Edit points on a curve or surface
    • Cut and divide surfaces
    • Mirror geometry across a symmetry plane
    • Edit normals
    • Profile curves (trim curves, curve on surface)
  • Import geometry from other objects
  • Use groups to organize geometry
  • Combine and filter groups
  • Specify groups
  • Quadratic primitive shapes
  • Polygons and meshes
    • "Box up" modeling tools
    • Bevel polygons
    • Example: Beveling a polygonal face
    • Subdivide polygonal surfaces
    • Repair polygonal models
  • Splines
  • NURBS Curves and Surfaces
    • Refine NURBS geometry by pasting
    • Trim NURBS surfaces
    • Creating a sharp point in a NURBS curve
  • Subdivision surfaces
  • Bezier Curves and Surfaces
  • Metaballs
  • Mix geometry types
  • L-systems
    • L-system basics
    • Create an L-system
    • Limit L-system growth inside a shape
    • Use modeled geometry in an L-system
    • Arrange geometry instances with L-systems
    • Production rule syntax
    • Turtle command reference
    • L-system expression functions
    • Advanced L-systems information
    • Example: Lightning letters
  • Brush Tools
• Animate
  • Introduction to animation in Houdini
    • Animation styles
  • Animation controls
  • Use the playbar to control animation
  • Color coding for keyframes and parameters
  • Set keyframes
  • Set and manage keyframes in the parameter editor
  • Use the playbar to edit keyframes
  • Channel groups
  • Manipulate animation channels
  • Animate objects along paths
  • Create a flipbook animation
  • Flipbook blocking
  • Animate cameras and lights
  • Cut between cameras
  • Tips and tricks
• Characters
  • Common operators and tools
  • Kinematics
  • Rig a skeleton
    • Rigging tips and guidelines
    • Two approaches to rigging
    • Draw bones
    • Edit bones
    • Position a Null at the end of a bone.
    • Blend between multiple IK goals
    • Reverse foot setup
    • Create and control bones with a curve
    • Set the rest angle of a joint
    • Mirror a skeleton
    • Blend between posing with IK and rotations
  • Bind skin to a character (capture geometry)
    • About capture weights
    • Posing the character for capture
    • Capture geometry by proximity
    • Paint capture weights
    • Transfer capture weights between characters
  • Deform characters and skin geometry
    • Squash and stretch
    • Wire deformer
      • Vary the capture radius along a wire deformer
    • Morph between geometry shapes
    • Muscle-driven deformation with Inflate
    • Lattice deformer
  • Pose and animate a character
    • Pose a character
    • Pose bones using temporary IK
    • Keyframe character animation
  • Blend parenting of objects
  • Make a character into a digital asset
  • Troubleshooting characters
• Effects
  • Particles
    • How particle systems work
    • Create a simple particle system with the Particle SOP
    • Set up a particle system
    • Particle node flags
    • Reference geometry from a particle operator
    • Update the view when you change parameters
    • Emit particles
    • Use groups to organize particle behavior
      • Create particle groups
      • Combine and filter particle groups
      • Use groups to control a particle simulation
    • Control particle motion
      • Apply forces to particles
      • Visualize forces with template geometry
      • Directly set motion attributes
      • Limit particle speed
      • Mass, drag, and charge
    • Control particle network flow
    • Particle collisions and interactions
      • Detect collisions
      • Make particles follow a leader or leaders
      • Make particles orbit a center point
      • Make particles attract or repel each other
      • Slide particles along surfaces
      • Limit the number of collisions a particle can have
      • Transfer attributes from geometry
    • Have particles react to events
      • Example: Generate particles when a collision occurs
    • Manually set particle attributes
    • Inspect attributes on particles
    • Render particles
      • Instance geometry on particles (particle replacement)
      • Set the rendered appearance of particles
      • Use particles as geometry
    • Vector vs Component Definition
    • Troubleshooting particles
    • Particle tips and tricks
  • Spatial audio
    • Set up a 3D audio animation
    • 3D audio cookbook
    • Spatial audio filters
  • Dynamics
    • Introduction to Houdini dynamics (DOPs)
    • Dynamics node flags
    • Create a simulation network
    • Rigid body dynamics (RBD)
      • Set up an RBD simulation
      • Create an RBD object
      • Apply forces to an RBD object
      • Constrain an RBD object
      • Glue RBD objects together and break them apart
    • Cloth
      • Set up a cloth simulation
      • Use constraints to pin and stitch together cloth
    • Wire solver
      • Set up a wire simulation
      • Create a wire object
      • Pin wires to points on another surface (glue constraint)
    • Make objects affect each other
    • Run and play back the simulation
    • Manage and combine the results of solvers
    • Control the rendered look of dynamics
    • Troubleshooting dynamics
• Shading and rendering
  • Shaders and textures
    • Introduction to shading in Houdini
    • Use the shader palette
    • Assign shaders to objects and surfaces
    • Layer multiple shaders
    • Create a shader
      • Important VOPs
      • Create a VOP network surface shader
      • Lighting models
      • Use textures in shaders
      • Create an interface for your shader
      • Use bump maps in shaders
      • Import information from a displacement or light shader into a surface color shader
        • Example: Importing information from a displacement map
      • Create a shader from pure VEX code
    • View the code generated by a VOP network
    • Switch shaders based on the renderer
    • Textures
      • Set up the texture editor
      • Add texture coordinates (UVs) to a surface
      • Edit UVs
      • Bake texture coordinates onto a model
      • Save an image of the UV layout
      • Generate a mipmapped texture file
      • Pelting
        • Example: Basic pelting
        • Example: Painting spring tension
        • Example: Using a pelting frame
      • UV Brush
        • Example: UV Brush
  • Lights and shadows
    • Light types
    • Create and position a light
    • Light shaders
    • Edit lights
    • Shadows
    • Look through a light
    • Light linking and shadow linking
  • Cameras
    • Create a camera
    • Position and point a camera
    • Control and look through a camera's view
    • Control camera focus, clipping, and frustum interactively
    • Camera parameters
    • Shake the camera
    • Tips
  • Rendering
    • Introduction to rendering in Houdini
    • Output drivers
    • Set up to render
    • Useful mantra settings
    • Simulate atmospheric effects like fog
    • Simulate motion blur
    • Render the scene/animation
    • Control dependencies between renders
    • Process the image after rendering
    • Temporarily disable outputs
    • Save and reuse IPR caches (advanced)
    • Render control window
    • Tune the render
    • Troubleshooting Mantra rendering
    • Troubleshooting output drivers
  • MPlay image and animation viewer
    • Open images in MPlay
    • Save images from MPlay
    • Control flipbooks and renders in MPlay
    • Use multiple viewports in MPlay
    • Load MPlay images into memory to improve playback (caching)
    • Play audio in MPlay
    • MPlay menus
      • MPlay menu bar controls
      • Viewport Context Menu
      • File menu
      • Settings menu
      • Tools menu
      • Images menu
    • MPlay windows
      • MPlay preferences window
      • MPlay file open dialog
      • Profile Manager
      • Sequence List
      • Audio Dialog
      • Display Options
    • MPlay command line options
    • Optimize playback
    • Script MPlay
• Compositing
  • About compositing in Houdini
    • Compositing terms and concepts
    • Types of compositing operators
      • Generators
      • Scoped filters
      • Masked filters
      • Pixel filters
      • Timing modifiers
      • Compositing/blending operators
      • Plane operators
      • VEX operators
    • Compositing node flags
    • Compositing methods
  • Set up a new compositing project
  • Create or load image data
    • Load image data into the compositor
    • Generate fills
    • Create shapes and text
  • View/preview the output of a node
    • Modify color output with look-up tables (LUTs)
  • Position, resize, rotate, and crop image layers
  • Adjust colors, levels, black point, and white point
  • Filter image data
    • Mask off areas of an image
    • Work with mattes
    • Generate mattes based on image colors (keying)
    • Blur or sharpen the image
    • Add noise
    • Distort or convolve an image
  • Blend or layer images
  • Compare two images
  • Work with planes
  • Output composited images
    • Save composited data to disk
    • Use compositor images in other nodes
  • Configure the compositor
  • Improve compositing performance
  • Compositing cookbook
    • Common image effects
    • Deep raster effects
  • Compositing tips and tricks
  • Create a custom COP with VOPs
  • Image guide file
• Reference
  • Environment variables
  • Panes
    • Viewer pane
      • 3D Viewer pane
      • CHOP viewer
      • Compositing viewer
      • Particle viewer
    • Channel editor
      • Channel editor graph view
      • Channel editor table view
      • Channel editor dopesheet view
    • Network editor
    • Parameter editor
    • Channel list
    • Details pane
    • Handle list pane
    • Tree view
    • Take list pane
    • Bundle list pane
    • Parameter spreadsheet pane
    • Light linker pane
    • IPR viewer pane
  • Windows
    • Main Preferences
    • Main window
    • Display Options window
      • Display Options (3D viewer)
      • Network Editor Display Options
    • Camera Parameters window
    • Aliases and Variables window
    • Operator Type Properties window
    • Create digital asset dialog
    • Operator Type Manager window
    • Hotkey Manager window
    • Desktops window
    • Composite Project Settings window
    • Textport window
    • Performance Monitor window
    • Audio Panel
    • File dialog
    • Global Animation Options
    • View Flipbook options (Save Viewport) window
    • Snap options window
    • Export channels window
    • Toolbar manager window
    • Node browser window
    • Persistent manipulator editor window
    • Cache manager window
  • Image viewer interface
    • Work with images in the image viewer
    • Analyze image problems in an image viewer
    • Compare images in the image viewer
    • Link and unlink viewports
    • Image viewer toolbars
    • Image view
    • Timeline view
    • Graph view
    • Display Options window (image viewer)
  • Menus
    • Main menus
      • File menu
      • Edit menu
      • Settings menu
      • Tools menu
      • Windows menu
    • Desktops menu
    • Takes menu
    • Pane menus
      • Pane menu
      • Network menu
      • Operator menu
      • Network View menu
  • File formats
    • External vs. internal file formats
    • Write a custom importer/exporter
    • Geometry file formats
      • .geo format
      • Geometry format descriptions
    • Channel file formats
      • Channel format descriptions
      • Load and save channel formats
    • Scene description formats
    • Image file formats
      • .pic images
      • 16-bit image formats
      • RAT (random access texture)
      • Targa/Vista images
      • TIFF images
      • Vertigo images
      • Wavefront images
  • Standalone utilities
    • Image Tools (iTools)
      • Families of Image Tools
      • iblur - Blur Image
      • ibulge - Bump Image
      • ibumpmap - Create BumpMap
      • icineon - Convert Cineon
      • iclear - Clear Range
      • icomposite
      • iconvert - Convert Images
      • icp - Copy / Crop Image
      • icurve - Lens Curvature
      • idof - Depth of Field
      • iexabyte - Exabyte Tape
      • ifilter - Filter / Blur
      • iflip - Flip Image
      • iflop - Reflect Image
      • ifractal - Fractal Image
      • ihot - Hot Video
      • iinfo - Image Info
      • ijpeg - Convert jpeg
      • ilookup - Gamma Correct
      • imdisplay - View Sequential Images
      • inewtoold - Convert Old .pic
      • ipaint - Mini-Paint
      • iprint - ASCII Values
      • iquantize - Minimize Colors
      • iramp - Convert Ramp
      • iscroll - Scroll Image
      • ishear - Skew Image
      • isi - Convert to Softimage
      • isixpack - Make Reflection Map
      • istipple - Apply Noise
      • itim - Convert to Sony PSX
      • izg - Convert Z-Depth Images
      • izmatte - Composite RGBA/Z
      • hmvplay - Play Houdini Movies
      • hmvrecord - Record Houdini Movies
      • mcp - Movie Conversion
      • minfo - Display Movie Info
      • redit - Color Ramp Editor
    • Geometry Tools (gTools)
      • Polygon Tools
      • geo Format tools
      • gplay - View 3D Geometry
      • greduce - Polygon Reduction Tool
    • Channel Tools (chTools)
      • Channel Tools
    • hCommands
      • hCommands
      • dsparse - Dialog Script Parse
    • spy
      • spy - Quick Help Reference
      • Starting spy
      • Navigating With spy
      • Working with Files
      • Displaying Files Using less
      • UNIX Commands From spy
      • Command History
      • Help & Other spy Commands
      • Customizing spy