Bifrost 2.7.1.0 is a feature release with new capabilities, performance improvements, and bug fixes, and Bifrost 2.7.1.1 is a patch release with a digital signing update. They are available for Maya 2022, 2023, and 2024 from the Autodesk Accounts Portal. See Bifrost for Maya Compatibility for more information.

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

Release Highlights

Value display expressions

You can add node value display to any node by renaming it with an expression that includes the name of an input port inside curly braces, for example, my function at {input}.

For editable compounds, you can also set a value display expression when the Customize UI editor is open by clicking on the compound's header on the Parameters tab. Display expressions are included with compounds that you publish.

In addition, value display now shows labels for combo boxes instead of the underlying values.

Detachable Watch Points

You can now detach a watchpoint from its connection wire by dragging its eye icon or the table header anywhere in the graph view. The table is joined to the wire to show which data is dispayed.

To return the watchpoint to the wire, double-click the eye icon or right-click the icon and choose Return to Wire. You can also remove the watchpoint itself by Alt+Shift+dragging across the dotted line.

Sticky notes

The formatting bar that appears when a sticky note has been selected now has a gripper on the left. The gripper lets you use the mouse to move the sticky note without clicking outside the note to finish editing text.

In addition, the sticky note colors have been made darker and more saturated based on user feedback.

Other user interface improvements

• Clicking on a sticky note, watchpoint, or node automatically brings it to the front of others in the graph view.

• UI performance is faster, especially for sliders on Macs and zooming with backdrops.

• You can right-click on a Bifrost graph in Maya's Outliner and choose Open in Bifrost to open the graph in the Bifrost Graph Editor.

• All nodes where you can specify a component now have dropdowns that let you quickly select a common component such as point_component. You can still type in a component name.

• There is now a pause when dragging a wire to a port group before it opens.

• Shift-clicking on a port group in the parameter editor now opens or closes all port groups.

• All color inputs now use color pickers.

• Many input ports now have soft minimum and maximum values for sliders.

  • Fractions, weights, sizes, starts, iterations, and many others have minimums of 0 and no maximum.
  • Interpreted auto ports used as weights become sliders with a minimum of 0 once you set the port's value type to float.
  • Ports with units of radians range from –pi to pi.
  • Ports with units of degrees range from –180 to 180.

Scene info

The new scene_info node returns the location of the current file and project. This is useful for relative paths in USD as well as many other things.

If the scene is referenced, the scene paths are taken from the scene being referenced. For example if the scene alice.ma contains a Bifrost graph, the scene paths refer to alice.ma even when alice.ma is referenced into another scene. This means that if the graph in alice.ma references a "sidecar" file like a cache or USD layer, that reference still works when alice.ma is included as a reference in another file like shot003.ma in another directory.

Component tags

Component tags on Maya scene geometry are now included when you import the geometry into the graph. You can control which tags to transfer in the parameters of the input node.

Tags are also included when you convert an output mesh to a Maya mesh. You can control which tags to transfer in the parameters of the bifrostGeoToMaya node in Maya's Node Editor.

Internally, tags are represented as arrays of Booleans, where true means that the corresponding point, face, or other component is a member of the tag. You can use the get_component_tag and set_component_tag compounds to work directly with tags in the graph.

The interpret_auto_port_as_component_tag node can convert between different representations of tags. It can accept a tag name (string), array of indices, or an array of Booleans and return both the corresponding array of Booleans and array of indices. This is useful for including in your own compounds for processing components that can be specified in different ways.

Mesh scope

The mesh_scope node can visualize data regarding points, faces, face edges, adjacency, face vertices, and more. It is very useful for diagosing issues with meshes.

Smooth strands

The smooth_strands node averages the values of each point's value with those of its neighbors along the same strand. By default it smoothes the point positions, but it can be used to smooth any list of geo properties whether or not that includes the point positions.

Voxel smoothing

The smooth_voxel_property node has new parameters that are especially useful for smoothing a level set that has been created from points or particles.

• You can set the filter mode used for smoothing: Gaussian, Mean, or Median.
• You can set the number of iterations for performing the smoothing operation.

Other modeling improvements

• The duplicate_points node always transfers required properties.
• The transfer_properties_by_2d_indices node is significantly faster.
• The merge_geometry node is now entirely implemented in the graph, and can transfer properties of any type.

Volume rendering

Viewport rendering of volumes is faster, more accurate, and more stable. In addition, the translation of the volume is skipped if the volume is not changing, such as when editing a paused simulation graph where an identical volume is generated.

Arnold rendering of Bifrost volumes is also significantly faster.

USD improvements

There are two new nodes for working with USD in the graph:

• get_all_attribute_names
• get_authored_attribute_names

Other new nodes

• filter_meshes
• filter_points
• get_points_structure
• copy_properties
• erase_geo_properties
• update_strands_point_neighbors
• extrude_faces
• force_pull_port

Other changes

• The output of the mesh_to_volume node is now deterministic. Internally, the min_hole_radius that is used for filling gaps when voxelizing in Solid mode is clamped to be at least the voxel size (determined by detail_size and resolution_mode).
• The write_OpenVDB node now correctly exports velocity data when using post_refine_aero. This allows Arnold and other renderers to render VDBs from Bifrost with correct motion blur.
• On macOS, the preference for one-button mice is now respected. This allows navigating the graph editor using the Command or Command+Option modifier keys, making Bifrost much more usable on MacBooks without mice.

Arnold and USD Compatibility Information

Bifrost 2.7.1.0 works with the following:

• Arnold for Maya 5.3.1.1 (Arnold 7.2.1.1)
• MayaUSD 0.23.0 (USD 22.11-ad1) for Maya 2024
• MayaUSD 0.23.0 (USD 21.11-ad1) for Maya 2022/2023

See Maya USD, Bifrost, and Arnold compatibility for more information.

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

Bifrost 2.7.1.0 contains no changes that break backward-compatibility compared to the previous version.

Changes in Detail