• The animation catalog lets you save, manage, and apply animations and single-frame poses to an animation scene, allowing you to reuse animation across different projects.

• The motion mixer allows you to combine and edit the animation clips of multiple characters in a timeline-based view. You can also apply additional effects to change the look and behavior of your final animation.

• Upstream animation layers can now be inherited by an animation scene using the APEX Scene Animate SOP’s Inherit Animation Layers from Input parameter. This allows for procedural chaining of animation using multiple APEX Scene Animate SOPs.

• You can retarget animation onto a character in your scene using the APEX Animation from Skeleton SOP.

• The full body IK tool applies full body inverse kinematics to character rigs, letting you pose characters by adjusting high-level targets rather than manipulating individual joints. This helps to streamline complex character posing and motion editing while preserving natural joint behavior.

• You can now create constraints from the core animate state using the H hotkey (the dedicated constraint tool has been removed). In addition to regular (offset) constraints, you can create lookat, multidriver, and pin constraints.

• The APEX Configure Ragdoll recipe streamlines the process of setting up a ragdoll character for the animate state. Ragdoll parameters have also been added to the APEX Scene Add Prop SOP to simplify the process of adding a prop to a ragdoll scene.

• Tethers allow you to attach objects to each other in the ragdoll tool.

• The mirror pose functionality has been updated so you can add keyframes on mirrored controls, view the intersection between the character and mirror plane (Plane Intersection), and specify the mirror plane to follow a joint (Follow Joint).

• The options for baking animation are now in the settings HUD under the Bake tab, and can be used from within the various tools in the animate state. There is also a new hotkey, B, that bakes out animation.

• In selection sets, there are new options for selecting and displaying controls and characters (Select All Controls, Select Descendant Controls, Show/Hide All Characters/Controls), and organizing sets (drag and drop items in a set, Sort Controls, Replace Characters in All/Selected Sets, Expand New Sets, Expand All Controls by Default, Change Item, Relabel Control). You can also apply imported sets to specific characters.

• In the animate state, there are new hotkeys to easily grow, shrink, and change a selection of controls.

• There are new hotkeys for selecting all controls (⌃ Ctrl + A), toggling the transform handle visibility ('), toggling pivot mode (Insert), and cycling through the handle modes backwards (⇧ Shift + Y). There are also other actions that are available in the animate state that are not assigned to specific hotkeys, leaving it up to the user to configure as needed.

• Skin controls allow you to pose characters by selecting and dragging on the character’s skin.

• You can customize the look of the animate state transform handle through Houdini’s handle preferences, which can be accessed through the Open Handle Preferences button in the animate state’s handle parameters window. In Houdini’s handle preferences, turn on Apply APEX Handle Settings Automatically to immediately apply any changed settings in the animate state.

• In the animate state’s handle parameters window, there are options to Hide Controls During Scrub and Hide Controls During Drag. Defaults for the control-related preferences can be set in Houdini’s handle preferences.

• Improvements have been made to the transform handle’s axis snapping behavior.

• In the animate state parameters HUD, you can set and delete keyframes for the transform components of a control.

• In the animate state settings HUD, you can show or hide a control’s transform limits using the Show Transform Limits option.

• In the animation layers pane, you can now select from multiple animation clips in the scene.

• Version 2.0 of the APEX Scene Add Animation SOP adds animation to a scene as an animation clip (v1.0 added animation as raw channel primitives). Version 2.0 of the APEX Scene Invoke SOP presents a cleaner parameter interface and simplified workflow for evaluating the geometry in an animation scene. See animation workflow for examples uses of these nodes.

• The APEX Scene Copy Animation SOP copies animation between animation scenes. See the motion mixer for an example.

• On the APEX Scene Animate SOP, the Edit Animation parameter allows you to stash, delete, and rename the animation clips in the current scene.

• New parameters on the APEX Scene Add Prop SOP allow you to add multiple props to an animation scene (Import Prop Collection), specify how to handle animated props (Animation), and configure the control for the prop (Add Skin Control, Visible).

• On the APEX Configure Character SOP, the Bind Multiple Configurations parameter allows you to specify multiple naming patterns for controls when mirroring poses in the animate state, and the Root Control parameter specifies the TransformObject node to tag as the root control. There are also new parameters used by the full body IK and motion mixer tools.

• On the APEX Scene Add Character SOP, the Rename Ragdoll and Rig Path parameters allow you to rename a ragdoll character in an animation scene.

• On the Electra test geometry, you can specify a name for the Electra ragdoll using the Ragdoll Character Name parameter. There are also new parameters to configure Electra for use with the full body IK and motion mixer tools.

• Skeleton joint limits can be initialized from the limits set on the rig. This can be done with the following parameters on the Configure Joint Limits SOP - Initialize Limits from Rig, Use Packed Character, Skeleton Path, and Rig Path.

• The Ragdoll Solver SOP now supports animating the parameters for stiffness, damping ratio, rest length scale, and the enabled state for external constraints. You can also use the parameters Position Limit Stiffness, Position Limit Damping Ratio, Angular Limit Stiffness, and Angular Limit Damping Ratio to adjust the extent to which the solver attempts to enforce the ragdoll’s position and rotation limits.

• On the playbar, support has been added for the ripple tool, which allows you to move all the keys before/after the cursor location. On the dopesheet, support has been added for backward ripple.

• In the graph editor, the Value/Time Mark Handles option has been renamed to “Constrain to Axis”. To match the new name, the option now does the opposite of its previous behavior.

• In the graph editor and dopesheet, you can pan to the current frame using the Scroll to Current Frame option.

• Improved performance for panning and moving a large number of keys in the graph editor.

• The Autorig Builder is an extension of the auto-rigging SOP workflow. It allows you to interactively apply and configure pre-built and custom rig components for a character through the viewport. This makes the character setup process more intuitive while maintaining the flexibility of proceduralism.

• The Otto test geometry is a realistic male character complete with a biped rig and anatomically-correct muscle and skeletal bone geometry. You can use him as a starting point for human-like creatures and bipeds, and for adding muscles to your character.

• Version 2.0 of the Electra test geometry has an updated skeleton and rig that follows industry-standard mechanical setups. It includes features such as twist joints, IK and FK finger control options, and setups for reverse foot, auto clavicle, and blendable IK/FK for the limbs.

• The APEX Edit Graph SOP has been renamed to APEX Graph. You can now input a character folder structure into the APEX Graph SOP, which automatically displays the contained rig (specified in the Graph Path parameter) in the APEX network view. You can also enter the animate state on the APEX Graph SOP and see a visual representation of the graph as you update it. Additional new parameters allow you to store subnets as subgraphs and save them to disk (Subgraphs section).

• The fuse graph operation in the APEX Autorig Component SOP allows you to merge rig functionality from a graph into an existing rig, providing a modular workflow for making updates to your rig.

• The APEX Pack Character and APEX Unpack Character SOPs provide a convenient way to convert KineFX characters (with skin, rest pose, and animated pose) to a character folder structure. See the character folder structure for example uses of these SOPs.

• The updated APEX graph functionality, along with the new and updated APEX graph nodes are listed here.

• Version 3.0 of the APEX Autorig Component SOP has an updated interface and additional options including the ability to customize pre-built rig components and save them to your component library. The second output of the APEX Autorig Component SOP is now in a packed folder structure.

• Several new pre-built rig components are available from the APEX Autorig Component SOP, including the limb, hand, foot, neck, scapula, ulna, root, and twist joints. There are also new utility components joint rotate corrective, clean, and rename.

• Version 2.0 of the spline rig component has options for interactively squashing and stretching a spline, more options for configuring spline controls, and an improved setup for custom controls.

• Version 2.0 of the blend shape rig component allows you to create custom sliders for your blend shapes.

• Version 2.0 of the multi IK rig component has an updated interface as well as additional parameters for naming controls (Driver section).

• On the bone deform rig component, you can delete the capture attributes on the geometry using the Delete Capture Attributes parameter.

• On the IK/FK blend rig component, you can promote the translate, rotate, and scale components of the FK controls in the Settings tab.

• On the reverse foot rig component, there is a new rotational control for the toe, and mirror tags are no longer needed on your character before using this component. See rigging a character for an example.

• On the look at rig component, you can promote the translate, rotate, and scale components of the driver, target, and up controls in the Driven tab. In addition, the lookataxis and lookupaxis parameters allow you to align the driven node to the look at target and up positions.

• You can create interfaces for graph inputs using APEX Script.

  

• In APEX Script, you can output logging information, access and set vector and matrix components, and specify a name for a subgraph or subnet output port in the function return type (see user-defined functions for an example). There is also support for predefined constants, a + operator that extends arrays, and an alternative form of the if statement.

• When creating subgraphs in APEX Script, you can use keyword arguments in the @subgraph decorator to add properties to your subgraph.

• In addition to the APEX path pattern %tag() function, you can filter for tags on graph nodes and ports using an alternative syntax, #<tag_name>.

• Node and port tags can now contain double colons.

• The APEX path pattern syntax has been expanded to include rules for filtering and selecting points in a geometry and joints in a skeleton.

• On the APEX Script SOP, you can save and load the source snippet for subgraphs (Export Snippet, Load as Snippet), save and load the parameter interface, header, and footer for text files (Save Text, Save/Load Parm Interface, Save/Load Header), preview subgraphs in the APEX network view (the Show parameter’s Subgraphs option), specify a version of APEX functions to use (Application Version), and choose whether to keep the name metadata in the decompiled code (Keep Node Names).

• On the APEX Invoke Graph SOP, the Error Handling parameter is now set to Abort by default, and the Output Type Info parameter adds type information to the output dictionary attribute for the types that don’t have a direct representation in dictionary attributes. You can also specify graph ports in the Bind To Geometry Parameter and Bind Output Geometry parameters.

• The APEX Configure Graph SOP allows you to configure the parameters for constraint and component graphs.

• The Packed Folder Copy SOP copies, renames, and moves data in the character folder structure.

• Attribute Adjust Tags is a new alias to the Attribute Adjust Array SOP, which is used to add tags to skeletons.

• There are new control shapes cogwheel, fk, ik, loop, sphere, and sphere_m.

• The Skeleton SOP now defaults to using +X for the primary axis and +Z for the secondary axis.

• On the Skeleton Mirror SOP, the Mirroring Style parameter is now set to By Rotation by default.

• On the Orient Joints SOP, the Reference Vector parameter is now set to the +X axis by default.

• The APEX Rigscript Component SOP is now deprecated. Its functionality has been rolled into the APEX Autorig Component SOP with the Build Rigscript parameter.

• The APEX Autorig Component v1.0 SOP is no longer supported. This node was introduced in Houdini 20.

• You can import character data from glTF files using the GLTF Animation Import, GLTF Character Import, and GLTF Skin Import SOPs.

• On the FBX Animation Import SOP and FBX Character Import SOP, the fbx_node_type attribute specifies the type of scene element associated with the corresponding FBX node.

• On the FBX Animation Import SOP, FBX Character Import SOP, and FBX Skin Import SOP, the Normalize Joint Scales parameter normalizes the scales of the joints in the imported scene.

• On the FBX Animation Import SOP, FBX Character Import SOP, FBX Skin Import SOP, and FBX CHOP, the Remove Namespaces from Joint Names parameter removes any namespace prefixes from the joint names when importing an FBX file.

• On the ROP FBX Animation Output SOP, ROP FBX Character Output SOP, Filmbox FBX Animation ROP, and Filmbox FBX Character ROP, the Joint Display Scale parameter allows you to modify the size of the skeleton joints in an FBX file.

• On the SOP Character Import LOP, the Partition Attributes parameter has been renamed to Subset Attributes, and the Treat Polygons as Subdivision Surfaces parameter has been promoted from the SOP Import LOP, allowing subdivision for imported mesh primitives.

The following formats can be read:

• .aac

• .aiff/.aifc

• .flac

• .m4a

• .mp3

• .ogg

• .wav

The following formats can be written:

• .aiff

• .flac

• .mp3

• .ogg

• .wav

The following formats are no longer supported:

• .au

• .it

• .mod

• .mp2

• .s3m

• .sf

• .snd

• .spx

• .xm

Additional changes:

• The maximum sample rate has been increased to 48 KHz on all platforms.