Updated to version 1.8.6

version 1.8.6 (Mar 26 2026)

• FLIP Fluids 1.8.6 includes improved Blender 5.1 support, USD export support, as well as bug fixes and improvements.
• Video Overview: [Video Available Soon]
• Compatibility Notes:
  • FLIP Fluids 1.8.6 is officially supported in Blender 4.5 to Blender 5.1.
  • Blender 5.2: At this moment there are no known compatibility issues specific to Blender 5.2 Alpha, but this could change as Blender 5.2 develops (Blender 5.2 Support).
• Added: Universal Scene Description (USD) export support (Documentation).
  • USD is now the recommended export format over Alembic as USD supports more features and full FLIP Fluids export compatibility.
  • A FLIP Fluids simulation can be exported with the File > Export > FLIP Fluids Universal Scene Description (.usd*) operator.
  • A FLIP Fluids simulation can be imported back into Blender with the File > Import > FLIP Fluids Universal Scene Description (.usd*).
• Added: FLIP Fluids Preferences > General > Enable Linux Flatpak Compatibility option to improve support for Linux Flatpak installations of Blender (Documentation).
• Added: Domain > World > Friction value can now be set per side of domain.
• Added: Color and Mixing Attributes > Mixbox > Enable Grayscale Mixing mode option to avoid color biases when mixing black, white, or shades of grey.
• Added: Object modifiers can now be ignored within the simulation by including the text FF_SIM_DISABLE within the modifier name or node group name.
• Added: Various FF_GeometryNodes modifier features (Documentation):
  • Fluid Particle and Whitewater Random Rotation and Align to Velocity Vector on/off options are now factors on [0.0, 1.0] that control the amount of rotation.
  • Fluid Particle and Whitewater now contain a Displace > Store Transition Mask Attribute option that will add a flip_transition_mask to match the surface attribute of the same name when the FF_GeometryNodesSurface > Flatten Mesh Near Domain Boundary feature is enabled.
  • Fluid Particle and Whitewater now contain a Displace > Scale Particles With Transition Mask setting to scale particles towards this value according to the transition mask attribute.
  • Fluid Particle and Whitewater feature to duplicate and randomize particle positions within a distribution radius.
• Added: AVIF video file support to command line tools in Blender 5.1+.
• Improvement: The Mixbox plugin is now installed to a flip_fluids_mixbox_plugin directory next to the flip_fluids_addon installation directory so that Mixbox does not need to be re-installed every time the addon is updated.
• Improvement: Shift+A > FLIP Fluids > Quick Liquid operators will now select the FLIP Domain as the active object after the operator completes.
• Improvement: Added Domain > World > Sheeting Effects support for Source ID attribute. All attributes are now supported when using the Sheeting Effects feature.
• Improvement: Added upscaling support for the Source ID attribute when resuming a simulation at a higher resolution. All attributes are now supported when using the resolution upscaling feature.
• Improvement: Command line render operators now launch with additional performance logging information in Blender 5.0+.
• Bug Fix: Various fixes to the FF_GeometryNodes modifiers:
  • Fixed issue where FluidParticle and Whitewater collection instancing would offset the instances if the collection objects were not set at the world origin.
  • Fixed FluidParticle and Whitewater divide-by-zero glitch when Random Bias scaling was set to 0.
  • Improved Surface Flatten Mesh Near Domain Boundary geometry nodes feature.
  • Fixed issue where FLIP Fluids Sidebar > Geometry Node Tools > Update Geometry Node Modifiers operator may not transfer all settings from the older modifier.
  • Fixed issue where FLIP Fluids Sidebar > Geometry Node Tools > Update Geometry Node Modifiers operator may reorder and break the modifier stack.
• Bug Fix: Misc harmless Blender 5.1+ warnings.
• Bug Fix: Fixed issue where a new FLIP Domain could not be created after deleting a FLIP Domain without purging the old domain object from the Blend file.
• Bug Fix: Fixed issue where domain could run compatibility update routine multiple times when opening Blend file in newer addon versions.
• Bug Fix: Fixed misc errors when opening a Blend file created in the FLIP Fluids Demo in the full version.
• Bug Fix: Added workaround to issue where a Particle System object on the domain could prevent keyframed display/render settings from taking effect during the render. Initializing a FLIP Domain will now remove any Particle System modifiers on the domain object (Issue #71908)).
• Bug Fix: Fixed issue where fluid particle densities may not be correctly transferred to new particles when using the Domain > World > Sheeting Effects feature.
• Bug Fix: Fixed issue where fluid particle attributes may not be upscaled correctly when resuming the simulation at a higher resolution if the corresponding surface attribute was disabled.
• Removed: Attribute and persistent data warning popups have been removed to avoid user confusion and to remove clutter the UI. These warnings originally served the purpose of notifying the user to render from the command line when using certain features. Certain features do increase the chance of render instabilities, but we recommended to always render from the command line to avoid issues (Documentation).
• Removed: The FLIP Fluids Preferences > Enable Extra Features option that was enabled by default has been removed as it is no longer needed – all features are now enabled.