Added SkinSolidify 2.0: the new version of the skinsolidfy hda uses a different smoothing setup. This includes the ability to use a weight mask attribute to control the interior smoothing and reduce the potential for inversions.

Altered or removed several callbacks in the APEX 'graph' callback library.

• Updated the following callbacks to use ApexGraphHandles instead ofGeometries: graph::Layout, graph::AddSubnet, graph::PackSubnet,and graph::RewireOutputs.
• Renamed graph::AddSubnetNew to graph::SetSubnetContents.
• Removed the following callbacks: graph::MergeFromDisk,graph::ProcessParms, graph::InvokeCompiled, graph::SetTags,graph::SetParms.

Changed the default hotkey for adding new lines in the MuscleTensionLines Sop. The "A" key is now consistent with other "add" operations in the muscle family.

Changed the default hotkey for adding new lines in the MuscleTensionLines Sop. The "A" key is now consistent with other "add" operations in the muscle family.

Fixed a bug in the creation of the tendonmask attribute in cases where musclethickness is used.

Fixed a bug in the creation of the tendonmask attribute in cases where musclethickness is used.

Fixed an issue where some versions of the colormap/rawcolormap functions weren't handling variadic arguments properly. This may cause results of these functions to change if there were variadic arguments in use before.

Fixed an issue where some versions of the colormap/rawcolormap functions weren't handling variadic arguments properly. This may cause results of these functions to change if there were variadic arguments in use before.

Fix SOP Verb APEX nodes that use ordered multi-inputs only only expose them as an array geometry input instead of 9999 individual geometry inputs. Note that this breaks compatibility with APEX graphs that previously tried to use these APEX nodes.

Fix SOP Verb APEX nodes that use ordered multi-inputs only only expose them as an array geometry input instead of 9999 individual geometry inputs. Note that this breaks compatibility with APEX graphs that previously tried to use these APEX nodes.

The MuscleFlex sop's animated output had mismatched pointcounts when BoneCaptured deformation was combined with Frankenmuscles. This is now fixed.

The MuscleFlex sop's animated output had mismatched pointcounts when BoneCaptured deformation was combined with Frankenmuscles. This is now fixed.

hou.CopNode now refers to the new Copernicus nodes and no longer aliases hou.Cop2Node. To use old cops, use hou.Cop2Node.

APEX subgraph library .bgeo files are now only loaded using the `name` attribute. The previous legacy use of `callback_name` has been removed.

APEX subgraph library .bgeo files are now only loaded using the `name` attribute. The previous legacy use of `callback_name` has been removed.

XPU: Due to velocity blur bug fix with Mtlx geomprop reader on volume materials, volumes with motion blur may render slightly different.

Modified HQueue TOPs node's Resources parm to be multiparm instead of a space-separated list. If you previously had populated the Resources parm, then you will need to input the resource and respective quantity in the multiparm.

Updated the signature of many APEX callbacks to replace integer ports with boolean ports. This will cause many graphs to fail to compile. To assist in fixing errors in graphs, an "Add Missing Convert Callbacks" button has been added to APEX Edit Graphs.

Added a faster APEX graph sorting algorithm. The new algorithm results in slight changes to the specific ordering produced by operations like graph layout -- nodes within a vertical "level" may be shuffled due to this change.

Internally, this new algorithm is intended to be stricter with invalid graph topology, however for now this increased strictness is only enabled when the Error Handling Mode on the APEX Invoke Graph SOP is set to something other than "Ignore".

XPU: MtlxGeometryPropertyValue + USDPrimvarReader nodes now enforce strict-typing (matching Karma CPU) meaning if the type of the node (eg float) does not match the type of the primvar data (eg color3), then the default value on the node will be returned instead.

Added a new `@fps` automatic context option, which is equal to the global animation FPS setting (unless it is overridden). This context option value is now used to set the FPS and TCPS values on new stages created by LOP nodes, instead of accessing this value directly from the global FPS setting. This means that changes to the global FPS are now tracked and may cause LOP networks to recook. It also means that the `fps` context option can be set with an Edit Context Options LOP to override the global FPS setting when creating new USD stages. This could result in changed behavior of existing LOP networks if a context option named `fps` has been created in you hip file or LOP network.

Metallic MaterialX-based materials with high roughness may appear different due to a bug fix to conductor fresnel.

Gel light filters with textures applied to dome or spherical area lights on karma CPU renders may appear different due to texture coordinate bug fix.

LOP instance selection strings can now optionally be set to a format that includes the selected prototype primitive path along with the instance index (`/instancer[instance_index:/path/to/selected/prototype]`). LOP nodes which support point instance selections should, wherever possible, support this new selection string format in a backward compatible way moving forward. Because this new format is more precise and resolves ambiguities in the current format when dealing with nested point instancers, this new format will be made the default expected format in a future version of Houdini.

XPU: reverted the disabling of mipmapping on domelights (from 20.0.563)