Bifrost 2.7.0.0 and 2.7.0.1 Release Notes

Bifrost 2.7.0.0 is a feature release with new capabilities, performance improvements, and bug fixes. It is included with the Maya 2024 installer.

Bifrost 2.7.0.1 is a bug-fix release, and is available for Maya 2022, 2023, and 2024 from the Autodesk Accounts Portal. Bifrost 2.7.0.1, MayaUSD 0.23.0, and MtoA 5.3.1 all use a version of USD that provides important security enhancements. It is recommended that you upgrade to these versions of the plug-ins. For more information on version compatibility, see Maya USD, Bifrost, and Arnold Compatibility and Bifrost for Maya Compatibility for more information.

For installation help, see Download and install Bifrost for Maya.

Release Highlights

Bifrost 2.7.0.0 introduces MPM gel simulations, improved volume rendering in the viewport, and many other new and improved features.

MPM gel simulation

The new source_mpm_gel node is useful for simulating many materials such as icing, toothpaste, ketchup, melted chocolate, and foam, just to name a few possibilities. The yield_stress property controls the overall behavior — the larger the value, the more the gel will clump together and resist yielding under shear force.

NanoVTT — Improved volume rendering in viewports

NanoVTT is the new default renderer for volumes in the viewport. Volumes in the viewport match Arnold renders more closely, with support for colored volumes and physically-based thermodynamic emission scaling. Viewport volumes are rendered with an alpha channel, which is useful for playblasts that can be composited.

Explosion in the viewport

Optimizations let you view larger, more complex simulations without encountering time-outs from your graphics card, and you can use set_viewport_volume_settings to strike the optimal balance between render quality, features, and performance.

Note that NanoVTT does not support DirectX 11 or volumes using Power5 subdivision.

Bifrost-USD improvements

There are some new USD nodes:

add_applied_schema
remove_applied_schema

In addition, Bifrost 2.7.0.0 for Maya 2024 now supports USD 22.11.

New nodes

Several other new nodes have been added, including some compounds that were formerly available in the Rebel Pack:

aero_einstein_influence
aero_erode_density_influence
aero_noise_transport_influence
aero_pyroclastic_influence
get_from_interpolated_array
resample_strands
sample_any_array_by_weighted_sum
set_transferred_properties
set_voxel_fog_density
set_voxel_signed_distance
set_voxel_velocity
transfer_properties_by_2d_indices
transfer_properties_by_weighted_sum
update_face_tangent

New browser graphs

Several new sample graphs are available in the Bifrost browser, including graphs demonstrating the new MPM gel simulations. In addition, many existing graphs have been improved and updated.

Apple Silicon support

Bifrost for Maya 2024 now runs natively on both Apple Silicon and Intel Mac computers. The installer and installed plug-in are universal binaries (UB2). Additionally, Bifrost's JIT compiler Amino generates native Arm64 code when run on Apple Silicon.

`bifcmd` improvements

The bifcmd utility for executing Bifrost graphs outside of a host application like Maya has also been improved.

If the JSON definition file contains only one compound, it is executed automatically even if its name does not match the name of the file itself. You do not need to supply a --compound-name argument.
When using a JSON task description file, the definition files can be specified relative to the task description's location.
There are example task descriptions showing how to run a single compound, a sequence of tests, and an external operator. These examples can be found in the bifrost/examples/bifcmd/ directory of the Bifrost installation location.

Arnold and USD Compatibility Information

Bifrost 2.7.0.1 works with the following:

Bifrost 2.7.0.0 works with the following:

Bifrost content created from the procedural graph can also be rendered with Arnold for Maya (MtoA) version 4.0.0 or later. The most recent version of MtoA is recommended for the latest features, bug fixes and performance improvements. See Bifrost for Maya Compatibility for information about compatible versions of Maya and Arnold.

To obtain the latest Arnold for Maya installer, visit the Autodesk Accounts portal.

The first version of Bifrost that introduced Bifrost USD is 2.4.0.0. All versions of MayaUSD (available on github https://github.com/Autodesk/maya-usd/releases) that use the same USD version as Bifrost are compatible with Bifrost USD.

Older versions of MayaUSD can be installed alongside Bifrost, but Bifrost USD functionality will not be available.

Backward Compatibility Warnings

In Bifrost 2.7.0.1, the MAYA_USD_VERSION is 21.11-ad1 for Maya 2022 and Maya 2023, and 22.11-ad1 for Maya 2024. The '-ad1' suffix indicates that this USD version contains security enhancements. You may need to update your existing scripts as a result.

Changes in Detail

What's Fixed in Bifrost 2.7.0.0
Aero: Refinement during simulation blocks influences BIFROST-7822
Aero: Volume output does not have voxel tile tree levels BIFROST-8062
Backdrops: Crash moving a backdrop after undoing the explosion of compound BIFROST-8045
Backdrops: Deselect the originating backdrop/sticky during a copy/paste operation BIFROST-7886
Backdrops: Show full title text when selected or editing, truncate otherwise, and other title text behaviors BIFROST-7986
Browser Graphs: MPM gel ice cream and checker examples BIFROST-7821
Browser Graphs: Powder Explosion - remove 'ground_influence' BIFROST-7575
Browser Graphs: Remove watchpoints and reposition backdrop in embroidery browser example BIFROST-6953
Browser Graphs: Renderable MPM snow production example BIFROST-7722
Browser Graphs: Update graph examples with the new volume_mat shader BIFROST-7737
Compiler: Natively support Apple Silicon BIFROST-7215
Compound Loading: Crash when rendering when certain compounds are present BIFROST-8067
Compound loading: Missing type causes a crash on scene open BIFROST-6987
Geometry: Add any array weighted sum operations for certain types BIFROST-5954
Geometry: Implement transfer_properties_by_2d_indices node BIFROST-7436
Geometry: Implement transfer_properties_by_weighted_sum node BIFROST-7435
Geometry: merge_any_arrays - many-to-one any array indexing operation BIFROST-6149
Geometry: set_mesh_uvs crashes if vector3 connected to coordinates port BIFROST-8034
Interaction: Add Control-R shortcut to reset feedback state BIFROST-8032
Interaction: Port groups should not collapse when a wire is disconnected BIFROST-8002
MPM: Create basic_mpm_shell_graph BIFROST-7044
MPM: Gel node docs update BIFROST-8122
MPM: Ground plane influence support for grains BIFROST-7818
MPM: Helpers are not value semantic BIFROST-7957
MPM: Opening files with active/inactive points crashes BIFROST-7522
MPM: source_mpm_gel node BIFROST-7819
Maya Plug-in: Error logs when duplicating a graph with maya python command BIFROST-7848
Maya Plug-in: When parented to a keyframed group, graphShape does not render in viewport BIFROST-7573
NanoVTT: Artifacts when changing emission scaling BIFROST-7804
NanoVTT: Auto quality allows a faster FPS target BIFROST-8084
NanoVTT: Changing frames leaves the viewport in interactive quality BIFROST-8134
NanoVTT: Consistency with Arnold BIFROST-7760
NanoVTT: Crash when loading a vdb as Power5 BIFROST-8135
NanoVTT: Crash when reading VDB and displaying NanoVTT BIFROST-7815
NanoVTT: Default light slow performance BIFROST-7751
NanoVTT: Disabling depth test does not work for level sets BIFROST-8162
NanoVTT: Display_Volume option on MPM diagnostics crashes BIFROST-8201
NanoVTT: Fast rendering of volumes in wireframe mode BIFROST-7809
NanoVTT: In-app documentation for set_viewport_volume_settings node BIFROST-8172
NanoVTT: Maya crash related to openCL BIFROST-7806
NanoVTT: Maya crashes with erased voxel_signed_distance property BIFROST-8119
NanoVTT: Non-adaptive volumes disappear using auto quality BIFROST-7808
NanoVTT: Optimize Conversion for High res and fog BIFROST-7728
NanoVTT: Optimize depth test BIFROST-7786
NanoVTT: Optimize light volume computation BIFROST-7726
NanoVTT: Physically based emission defaults for Arnold_standard_volume_mat BIFROST-8115
NanoVTT: Playblast uses high quality rendering (non-interactive) BIFROST-8057
NanoVTT: Scene units in meters changes the NanoVTT viewing behavior BIFROST-8173
NanoVTT: Switch the default shader to render with NanoVTT BIFROST-8083
NanoVTT: Update preset to be physically plausible, making the new preset match in the viewport BIFROST-6794
NanoVTT: Using NanoVTT with aero_UVW_field_noise example results in artifacts BIFROST-8091
NanoVTT: Viewing doesn't work on a Mac Silicon M1 BIFROST-7803
NanoVTT: Viewport render settings node BIFROST-7653
NanoVTT: Voxel-artifacts in interactive mode with NanoVTT level sets BIFROST-7785
NanoVTT: voxel_color_scope should be off by default in aeroColor browser example in 2.7 BIFROST-8138
Node library: Switch all scopes and examples to not use the "color" property, as standard surface has forced the issue BIFROST-7107
Publishing: New default values of a republished compound do not persist until Maya restart BIFROST-6532
Rebel Pack: aero_einstein_influence BIFROST-8024
Rebel Pack: aero_erode_density_influence BIFROST-8025
Rebel Pack: aero_noise_transport_influence BIFROST-8026
Rebel Pack: Resample_strands crashes when a negative value is entered in minimum_resample_distance BIFROST-8078
Rebel Pack: aero_pyroclastic_influence BIFROST-8027
Rebel Pack: get_from_interpolated_array BIFROST-8013
Rebel Pack: resample_strands BIFROST-7597
Rebel Pack: set_voxel_fog_density BIFROST-7628
Rebel Pack: set_voxel_signed_distance BIFROST-7627
Rebel Pack: set_voxel_velocity BIFROST-7626
Rebel Pack: update_face_tangent BIFROST-7607
SDK: Update SDK example readme files for Apple Silicon BIFROST-8133
Sliders: rename UiSoftMin/Max to UISoftMin/Max, with back-comp support BIFROST-7540
Sticky Notes: Note height should adaptively change to hug all content BIFROST-7855
Sticky Notes: Quickly right clicking after double clicking to highlight text in a sticky note can trigger a crash BIFROST-8022
UI Editing: Customize UI popup window stays on top of other applications BIFROST-7370
UI Editing: RMB menu to Rename a port/parameter vanishes on undo BIFROST-7857
USD: add_applied_schema and remove_applied_schema nodes BIFROST-7955
Volume VP: Precomputed point lights missing quadratic falloff BIFROST-7807
Volume: Bif Volume crash when deleting a property (related to volume targets) BIFROST-7690
Volume: Nodes default to Power2 BIFROST-8124
Volume: Port groups and subgroups should be collapsed in set_viewport_volume_settings BIFROST-8171
Volume: convert_to_volume and Esc key crashes Maya BIFROST-7835
bifcmd: Should allow specifying only a json file (if it contains one compound) or specifying a compound found not in the json file BIFROST-7119
bifcmd: add an example task description json file to the bifrost examples BIFROST-8010
bifcmd: allow Bifrost Definition Files to be relative to Task Description JSON file location BIFROST-8087

Known Issues and Limitations
BIFROST-3144 Aero: Blue flame tile artifact when exporting and viewing combustion rate Tile or voxel artifacts may sometimes appear in blue flame (combustion rate).
BIFROST-822 Aero: Sourcing from a volume sometimes creates ghost voxels around emitter Occasionally, some ghost emissions may occur outside of the aero source geometry.
BIFROST-3150 Aero: combustion soot sometimes pulsates Occasionally a combustion simulation will produce soot which pulsates too much.
BIFROST-7914 Arnold-Bifrost: Exports of graphs into USD files with Arnold-USD don't work when kicking those USD files
BIFROST-7568 Arnold-Bifrost: Strands don't render properly when some strands have only 1 point
BIFROST-7091 Arnold-Bifrost: remaining delay to start first Arnold session due to Bifrost loading in Arnold
BIFROST-2279 Encapsulation: Creating a compound out of a node that is auto-looped may change graph behavior
BIFROST-3024 Errors: When using write nodes such as the write_OpenVDB node, the node's success port always returns "true" even when writing fails Workaround: Ensure that your folder and file names are valid when writing.
BIFROST-7896 Fan-in: Connections are lost if fan-in is disabled on a referenced node
BIFROST-6951 File IO: File browser does not automatically add file extensions (.abc, .vdb, .usd, etc.) on Linux
BIFROST-3626 File IO: Write/dump nodes do not work with non-ASCII characters in file path
BIFROST-5339 Graph Shape: Converting from graph shape to DG loses its material assignment if connected to Terminals
BIFROST-5509 Graph Shape: In-graph material assignments don't display in viewport when no material is assigned in Maya
BIFROST-7304 Interaction: Cannot enter very large long or unsigned long values in parameter editor such as numeric max If you wish to use a numeric max sentinel value, use a value node connected to "numeric_max" to compute the desired value in the graph.
BIFROST-3028 Materials: Input meshes will not have a material assigned if it has per-face shading, first material found is not used Per-face shading in input meshes is not supported at this time.
BIFROST-5927 Maya Plug-in: 2D array input values from skin cluster are not correct Per-influence weights and weight list nested arrays do not work when connected as a whole to 2D float array ports. However the per-influence weights sub-arrays can be connected to 1D array ports and work correctly.
BIFROST-2334 Maya Plug-in: Bifrost plug-in should unload and reload cleanly Unloading and re-loading Bifrost plug-ins within the same session of Maya causes instability and other issues.
BIFROST-3070 Maya Plug-in: BifrostGraph plug-in should load automatically when clicking the Shelf icons If this error appears when you click the Bifrost Graph Editor or Bifrost Browser buttons on the Shelf: // Error: line 1: Cannot find procedure "openBifrostGraphEditorFromSelection". You need to load the bifrostGraph plug-in. Do this by selecting Windows > Settings/Preferences > Plug-in Manager.
BIFROST-7377 Maya Plug-in: Material assignments are translated as selection sets when meshes are brought into the graph, slowing down translation To workaround the issue, assign the default material to the meshes, which will prevent translation of shading groups as selection sets, speeding up translation. 1. Select all polySurface meshes in Maya 2. RMB in viewport > Assign Existing Material > lambert1
BIFROST-2997 Maya Plug-in: On graph inputs, changing port types loses inputs and exposing ports do not maintain values
BIFROST-2330 Maya Plug-in: Scene loading doesn't trigger the vnn plug-in to load in mayapy Bifrost will still work in mayapy, but the VNN plug-in will not load automatically and therefore the VNN Python commands will not work. Workaround: To use VNN commands in mayapy, load the plug-in using the loadPlugin command first.
BIFROST-4447 Maya Plug-in: UV changes do not always update the graph
BIFROST-3551 Module paths starting with "///" are parsed incorrectly as "//" by Maya and Bifrost
BIFROST-1655 Node library: Conversion nodes do not behave correctly if the input is the same type as the output
BIFROST-3272 Publishing: "not a valid Amino JSON file" error appears if library config json file is in the search path
BIFROST-2532 Publishing: Cannot type in namespace field if there is an error, loses focus with each keystroke Workaround: Temporarily change the name of the compound in the publishing editor to remove the error, edit the namespace, then change the name back.
BIFROST-4911 Publishing: Re-publishing with renamed output port results in unfixable graph When re-publishing, if output ports are renamed and those ports are connected inside the graph in question, it can cause a corrupted connection to that graph. Reloading the scene will allow you to fix it.
BIFROST-2767 Publishing: Republishing is blocked in cases of signature change and no auto ports Workaround: Add a new port, re-publish the compound, then delete the new port, and re-publish again. This works because it only blocks in very specific cases of signature changes.
BIFROST-2729 Simulation: Slow simulation bounds performance Simulation bounds still lacks certain performance improvements.
BIFROST-3762 Sticky Notes: Annotations should support unicode
BIFROST-2604 VP2 Meshes: Face-vertex, face, strand, component and constant user data don't work in the viewport
BIFROST-5052 VP2 Volume: Aero fails to render with "Alpha Cut" Viewport 2.0 Transparency Algorithm
BIFROST-4668 VP2 Volume: DX11 mode Aero renders pink
BIFROST-2353 VP2 Volume: Fail to render in Viewport 2.0's OpenGL Legacy mode (only a white cube appears)
BIFROST-5515 VP2 Volume: Levelset/density volumes don't display with multisample anti-aliasing (MSAA) and DirectX
BIFROST-2573 VP2 Volume: Volumes should draw correctly with default material enabled In addition, volumes and other bifShapes don't draw correctly if Use Default Material is enabled for Viewport 2.0.
BIFROST-3278 VP2: Bifrost geometry displays with texture even in non-textured shaded mode
BIFROST-3383 VP2: Maya Bounding box override on bif shapes only works on volumes and not other geometries
BIFROST-1982 Volume VP: Multiple volumes in the viewport don't always render with correct transparency order
BIFROST-1593 Watchpoints: Not removable after port type change
BIFROST-5033 Watchpoints: data inside for-each is not deterministic