• FLIP Fluids 1.8.7 includes new geometry node features, bug fixes, improvements, and official Blender 5.2 LTS support.
• Compatibility Notes:
  • FLIP Fluids 1.8.7 is officially supported in Blender 4.5 to Blender 5.2.
  • For best compatibility, latest bug fixes, and full feature set, Blender 5.2 is recommended.
  • Blender 5.3: At this moment there are no known compatibility issues specific to Blender 5.3 Alpha, but this could change as Blender 5.3 develops (Blender 5.3 Support).
• Added: Implemented cache loading optimizations. Playback is now 3x - 9x faster, with higher performance gains for larger amounts of geometry.
• Added: FLIP Outflow > Gradual Outflow options to gradually remove fluid from an outflow as an alternative to immediately removing and fluid that enters the outflow.
• Added: A 3D UVW texture coordinate attribute to the fluid surface and fluid particles. This attribute stores initial particle UVW coordinates at the time that the fluid particles is spawned. This attribute can be accessed within an Attribute Node with the name flip_uvw from the Vector output. Can be used for basic texture projection effects.
• Added: FF_GeometryNodesFluidParticles features for filtering particles based on attribute values. Modifier contains settings to:
  • Delete particles outside of a Min/Max Velocity, Speed, and Vorticity Range, or outside of a color tolerance.
  • Scale particles towards a scale factor when near the Min/Max attribute range or as color reaches maximum tolerance.
  • Store the Min/Max range or color tolerance mapped to a [0, 1] attribute to be used in a shader or other geometry node modifiers.
• Added: FF_GeometryNodesFluidParticles instancing feature to instance a separate object based on Source ID attribute. Supports Source ID attribute values from 0 to 8.
• Added: FLIP Fluids USD Export > Incremental Save option in Blender 5.2+ to write the export file after exporting a specified number of frames to fix a memory usage issue during export (Issue #156402).
• Improvement: The Command Line Tools > Render After Bake feature will now run the bake and render process within the same terminal window instead of opening a new window when the render begins.
• Improvement: The command line renders will display the Blend filepath between frames to improve visibility of which command line process is being run.
• Improvement: The Command Line Tools operators will now launch terminals with a window title display the process and Blend file name.
• Improvement: The simulation baking console output and logging will now display the Blend filepath between frames.
• Improvement: Custom Domain > Debug drawing now displays with antialiasing in Blender 5.1+.
• Improvement: FF_GeometryNodes features will no longer take effect if the required attribute does not exist.
• Improvement: Reduced render memory usage when motion blur is disabled or the flip_velocity attribute does not exist.
• Improvement: FF_GeometryNodes instancing features will now inherit smooth/flat shading the instance object when the Shade Smooth Instances option is disabled.
• Bug Fix: Fixed memory limitations that would trigger std::length baking errors when running simulations with too large of a resolution or when simulating too many fluid or whitewater particles. There is now no limit to how heavy of a simulation can be run, other than hardware or time limits.
• Bug Fix: Fixed baking error if an object contains an uninitialized geometry nodes modifier with no set node group (Issue #667).
• Bug Fix: Fixed error that could be triggered during render, resulting in an incomplete render setup.
• Bug Fix: Fixed that could be triggered when installing an existing preset library location.
• Bug Fix: Fixed DivideByZero errors that could be triggered when operating on a domain that had not been fully initialized.
• Bug Fix: Various operator errors that could be triggered in the Cycles addon was not enabled.
• Bug Fix: Fixed issue where FLIP Force Field > Gravity Scale may not be computed correctly outside of the gravity scale width or max distance of the force field.
• Bug Fix: Fixed issue where FLIP Force Field > Gravity Scale was not being computed correctly inside of a volume force, resulting in fluid not matching the volume force shape closely enough.
• Bug Fix: Fixed USD export/import compatibility issues and format consistency between Blender 4.5 - 5.2.
• Bug Fix: Removed stray debug printouts to the Blender console.
• Bug Fix: Fixed deprecation warnings due to different Python versions between Blender 4.5 - 5.2.
• Bug Fix: Fixed string literal SyntaxWarning that could be triggered during save depending on CPU model name.
• Bug Fix: Fixed bug where Domain > Debug > Display Grid > X and Z Offset values were swapped when controlling grid offsets.
• Bug Fix: Fixed issue where UI material lists were displayed in reverse order. Added material categories to separate between FLIP FLuids Material Library and scene materials.
• Bug Fix: Fixed Compositing Tools issue where particles could not be scaled higher than 1.0.
• Bug Fix: Fixed issue where FF_GeometryNodes modifiers could display irrelevant settings for selected menus in Blender 5.1+.
• Bug Fix: Fixed issue where FLIP Domain update routines were not being run on a depsgraph update in Blender 5.1+.
• Bug Fix: Fixed logging bug that would log setting the Max Whitewater Particles value for every frame if the value was set to 0.
• Bug Fix: Fixed issue where some FF_GeometryNodes modifier keyframes would not take effect in the render.
• Bug Fix: Fixed issue where fluid particle or whitewater meshes may display empty geometry if multiple FF_GeometryNodes modifiers were chained together in the modifier stack or when 'cloning' the simulation mesh through an Object Info node.
• Bug Fix: Fixed <-Wmaybe-uninitialized> warnings during compile in newer versions of GCC.
• UI: Command Line Tools operators will now display an error popup if a Blend file save error is encountered such as permission or resource packing errors.
• UI: Various tooltip corrections.
• Example Scenes and Presets: Blend files and assets have been improved and updated for newer versions of FLIP Fluids and Blender.

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-186-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: https://youtu.be/3KDoTrQ4DhI
• 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.

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-185-nov-18-2025

• FLIP Fluids 1.8.5 includes many improvements, geometry node features, a variable density solver, bug fixes, and official compatibility support for Blender 5.0.
• Video Overview: https://youtu.be/3XghoDDRwbc
• Compatibility Notes:
  • FLIP Fluids 1.8.5 is officially supported in Blender 4.5 to Blender 5.1.
  • Blender 5.1: At this moment there are no known compatibility issues specific to Blender 5.1 Alpha, but this could change as Blender 5.1 develops (Blender 5.1 Support).
• Added: Variable density solver feature to Domain > World panel for mixed density liquids that float or sink (Documentation).
  • After enabling, each Fluid/Inflow object can be set to assign a density value to the generated fluid.
  • After baking, the density attribute values can be accessed from an Attribute Node with the name flip_density from the Fac output.
  • Tip: Rendering fluid particles shaded or hidden based on density can be useful for visualizing variable density simulations.
• Added: Various geometry node features for customizing the fluid surface, fluid particles, and whitewater simulation meshes (Documentation).
  • These features can be found in the FF_GeometryNodes modifier on the fluid surface, particles, and whitewater simulation meshes.
  • New Fluid Surface Modifier Features:
    • Motion Blur > Apply Simulation Time/World Scale - Automatically scale motion blur according to the baked simulation time and/or world scale for consistent screenspace motion blur. If applying simulation time scale to motion blur, you will no longer need to manually animate motion blur scale with the time scale for slowmotion effects. This feature will only take effect if the simulation was baked in the current addon version or later.
    • Meshing > Shade Smooth - Option to specify whether to smooth shade or flat shade the mesh.
    • Meshing > Remove Mesh Near Domain Boundary - Options to remove parts of the mesh near the domain boundary to create a surface-only mesh. Contains options to enable or disable ±X/Y/Z sides of the domain and distance from the domain boundary. This feature works similar to the Domain > Simulation > Meshing Against Boundary feature except that the result is not baked into the mesh and can be applied after the simulation.
    • Meshing > Flatten Mesh Near Domain Boundary - Options to flatten the surface mesh towards a water level near the edges of the domain boundary. Useful for compositing or combining the surface mesh into a larger ocean plane.
      • Feature should be used in combination with the Remove Mesh Near Domain Boundary feature, using geometry nodes or domain settings.
      • Water level can be specified using a Z value or the Z coordinates of an object.
      • Flattened Width - Width of the flattened edge at the domain boundary.
      • Transition Width - Width of the smoothed flattening transition.
      • Store Displacement Attribute - Store amount of applied Z displacement as a flip_displacement named attribute. Enabling is required for matching displacement in the whitewater and fluid particle simulation meshes.
      • Store Transition Mask Attribute - Store transition mask as a flip_transition_mask named attributes. Values are in the range [0.0, 1.0] where 0.0 is fully flattened and 1.0 is no flattening. Useful for fading out the edges of the fluid surface in a shader.
  • New Fluid Particle and Whitewater Modifier Features. The following features are supported on both the fluid particle and whitewater meshes.
    • Material > Apply Material - Option whether to apply the specified material to the particles. Disable to inherit material from instances if object instancing is used.
    • Motion Blur > Apply Simulation Time/World Scale - Same as modifier settings on fluid surface.
    • Particle > Particle Display Mode - Settings for how to display and render the particles.
      • None - Display the particles as raw vertices.
      • Point Cloud - Display the particles as a Point Cloud type object. This is the most performant method to render and display particles in Blender.
      • Instancing - Display the particles with object instances. This is the least performant method to render and display particles in Blender, but offers more customizations over the shape. Try to limit the amount of particles rendered using this method to avoid performance issues.
    • Point Cloud and Instancing Options:
      • Particle Scale - Object scale of particles in Blender Units.
      • Particle Scale Multiplier - Multiply particle scale by this value. Useful for precision scaling for small particle sizes.
      • Particle Scale Random - Amount of linear randomized particle scaling.
      • Random Bias - Random bias of particle scaling distribution. Values less than 1.0, bias towards small particles. Values greater than 1.0, bias towards large particles. Value equal to 1.0, no bias.
    • Particle Instancing Options:
      • Instancing Mode
        • Icosphere - Instance icosphere objects over the particles.
        • Object - Set a custom object to instance over the particles.
        • Collection - Randomly instance objects from a collection over the particles.
      • Randomize Instance Rotation - Apply a random rotation for each particle instance.
      • Align Instance to Velocity - Align instance Z axis to the particle velocity vector. Requires enabling the FLIP Velocity attribute before baking.
      • Shade Smooth Instances - Option to specify whether to smooth shade or flat shade the instance objects.
      • Realize Instances - Convert particle instances to mesh geometry. Required for transferring simulation or custom attributes the particle geometry. This option can generate a large amount of geometry and result in performance issues for large amounts of particles or for high geometry instances.
    • Displace > Match Flattened Surface Displacement - If the Surface Modifier > Flatten Mesh Near Domain Boundary option is enabled, apply the same displacement to the particle Z level.
    • Lifetime Based Particle Scaling - Scale particles at the end of their lifetime. Requires enabling the FLIP Lifetime attribute before baking.
      • Final Scale Factor - Particle scale factor at the end of the particle lifetime.
      • Scaling Duration - Duration of the scaling transition in simulation seconds.
      • Lifetime Offset - Time offset for when the scaling transition begins.
      • Store Lifetime Scaling Transition Attribute - Store transition values as a flip_lifetime_transition named attribute. Values are in range [0.0, 1.0], starting at 0.0 before scaling transition begins and ending at 1.0 when scaling transition is complete. Useful for shading the particles based on scaling transition.
  • New Fluid Particle Modifier Features. The following features are only supported on the fluid particle meshes.
    • Age Based Particle Scaling - Scale particles at the beginning of their age. Requires enabling the FLIP Age attribute before baking.
      • Starting Scale Factor - Particle scale factor at the start of the particle age.
      • Scaling Duration - Duration of the scaling transition in simulation seconds.
      • Age Offset - Time offset for when the scaling transition begins.
      • Store Age Scaling Transition Attribute - Store transition values as a flip_age_transition named attribute. Values are in range [0.0, 1.0], starting at 0.0 before scaling transition begins and ending at 1.0 when scaling transition is complete. Useful for shading the particles based on scaling transition.
    • Filter Particles by Source ID - Show or hide particles based on Source ID attribute. Requires enabling the FLIP Source ID attribute. Useful for selectively rendering particles based on the Fluid/Inflow object that they are emitted from.
      • Contains checkbox options from 0 to 8 to control whether to show or hide particles with the corresponding Source ID. For example, disabling checkbox 2 will hide particles with Source ID = 2.
  • Added FLIP Fluids Sidebar > Geometry Node Tools > Update Geometry Node Modifiers operator to update the fluid surface, fluid particle, and whitewater geometry node modifiers to the current addon version.
    • Operator will transfer older modifier settings to the updated modifier where possible to closely match the previous result.
    • Operator will not delete existing FF_GeometryNode modifiers or datablocks to avoid data loss. Existing modifier will be renamed with a BACKUP prefix and disabled from the modifier stack. This backup can be removed when no longer needed.
• Bug Fix: Fixed issues related to the File > Export/Import > FLIP Fluids Alembic (.abc) operators.
  • Fixed issue where exporter setup for fluid particle or whitewater may not be recognized by Blender's Alembic Exporter as animated meshes due to not containing any modifiers.
  • Fixed issue where exporter may not apply the fluid surface smooth modifier.
  • Fixed issue where exporter would continue simulation export when the simulation cache does not exist, resulting in an empty Alembic file.
  • Fixed issue where exporter would not export velocity attribute when meshes contained certain versions of the FF_GeometryNodes modifier.
  • Fixed export issue where simulation meshes would not be exported if the outliner render visibility was disabled.
  • Fixed issue where importer could unexpectedly set motion blur velocity attribute to (0, 0, 0) depending on export configuration.
  • Fixed issue where imported Alembic mesh may not be animated if the first frame did not contain geometry.
  • Fixed import issue where the FF_GeometryNodes modifier on Alembic meshes would contain features that were not supported due to unsupported/missing attribute or feature that require addon scripting.
• Bug Fix: Fixed warning messages related to deprecated bgl (OpenGL Wrapper) calls in Blender 5.0.
• Bug Fix: Fixed bugs related to EEVEE render engine name change in Blender 4.5 and later.
• Bug Fix: Fixed FF_GeometryNodes warning when setting material on invalid geometry.
• Bug Fix: Fixed issue where some keyframed FF_GeometryNodes modifier values would not take effect in the render (related to issue #71908). All keyframeable modifier values are now supported.
• Bug Fix: Fixed issue where an older Blend file compatibility update could trigger an error, resulting in a missing FF\GeometryNodes_ modifier on the fluid surface.
• Bug Fix: FLIP Fluids Sidebar > Initialize Motion Blur operator now only switches the render engine to Cycles when the current render engine is set to a renderer that does not support custom motion blur (EEVEE or Workbench) to avoid switching away from third-party renderers.
• Bug Fix: Added missing GPL license to command line operator scripts.
• Bug Fix: Fixed issue where a Point Cloud type object could be set as a FLIP type object, resulting in baking errors. A popup error will be displayed to notify the user that Point Cloud objects are not supported as FLIP objects.
• Bug Fix: Fixed 'RuntimeError: Error: KeyMapItem not found in KeyMap 3D View' error during addon unregistration that could be triggered if the keymap was unavailable.
• Bug Fix: Improved addon startup/registration performance by removing older and unused Blender 2.79 compatibility code.
• Bug Fix: Fixed issue where some fluid surface attributes (age, lifetime, whitewater proximity, viscosity, color) were offset by half of a voxel.
• Bug Fix: Fixed issue where Domain > Advanced > Simulation and Particle Stability > Viscosity Solver Max Iterations would be applied to the pressure solver instead of the viscosity solver.
• Bug Fix: Fixed baking errors due to deprecated and removed Animation & Rigging Python API calls in Blender 5.0.
• Bug Fix: Fixed bug where FLIP Lifetime attribute data could contain values less than the expected minimum value (ex: negative values).
• Bug Fix: Removed unsupported API call to depsgraph update during frame change. This call was required for render stability in earlier versions of Blender, but caused stability issues in newer versions of Blender.
• Bug Fix: Fixed issue where force field gravity scale would not be computed outside of the force field max distance bounds, resulting in incorrect gravity scale and box shaped artifacts when combining multiple force fields.
• Bug Fix: Fixed issue where object delta transforms were not applied to keyframed FLIP objects within the simulation.
• Bug Fix: Fixed issue where FLIP Fluids Sidebar > Compositing Tools would render the shadowcatcher pass by default.
• Bug Fix: Removed stray debugging console outputs during Blender shutdown.
• Bug Fix: Fixed error that would prevent Shift + A > FLIP Fluids > Quick Liquid operators from completing when the addon version does not contain built-in materials.
• Bug Fix: Fixed UnboundLocalError that could be triggered during render due to operating on an invalid simulation mesh object types.
• Bug Fix: Fixed issue where some presets assets contained an orphaned mesh data block that would result in an unrelated object to be imported from the asset library into the Blend file.
• Change: Default values for fluid particle viewport preview display are now set to the same value to avoid flickering during Surface/Boundary/Interior particle type transitions.
• UI: Updated collapsible panel UI elements to used modern Blender UI features.
• UI: Improved wording on 'Missing geometry nodes modifier' warning to direct the user to click the operator to resolve the issue.
• UI: Corrected FF_GeometryNodesFluidParticle > Particle Scale tooltip that contained text for another parameter.
• UI: Added a copy of the Domain > World > Global Force Field Weights to the FLIP Force Field object menu for convenience.
• UI: Fixed inconsistent capitalization of Skip Re-export option across the addon UI.
• UI: Updated Twitter labels to X (Twitter).
• Building/Compiling:
  • CMake: Removed building a standalone Alembic export executable. This feature is now built as a shared library.
  • CMake: Fixed MacOS RPATH configuration that prevented Alembic dependencies from being found.
  • CMake: Source files are no longer collected via CMake GLOB and are instead specified explicitly to avoid re-build errors. If adding source files, remember to add the file to the CMakeLists.txt sources list.
  • CMake: Corrected publicly linked libraries to private.
  • build.py: Removed build script option flags to supply Alembic and/or Imath dependency filepaths.
  • build.py: Script can now be supplied with a list of dependency filepaths to package within the addon with the -package-dependencies flag.
  • C++: Removed header include guards and replaced with #pragma once preprocessor directive.
  • Python: All compatibility code related to Blender 4.4 and earlier has been removed to simplify the code base.
  • Python: Increased minimum version compatibility to Blender 4.5.0 in blender_manifest.toml

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-184-jul-17-2025

• FLIP Fluids 1.8.4 adds a hotfix to correct a severe bug in the recent FLIP Fluids 1.8.4 (2025-07-14) release that can result in frequent render crashes and can prevent materials from being applied to the simulation. If you have installed the recent FLIP Fluids 1.8.4 release, please update to this new version and restart Blender.
• Compatibility Notes:
  • FLIP Fluids 1.8.4 is officially supported in Blender 4.1 to Blender 4.5.
• Bug Fix: Fixed bug that could result in frequent render crashes and prevent applying materials when applying workaround for issue #71908.
• Bug Fix: Fixed UI bug where the Command Line Tools > Bake > Render After Bake menu could be missing a Skip rendered frames option.

• FLIP Fluids 1.8.4 includes many improvements, smaller features, and bug fixes, as well as official compatibility support for Blender 4.5 LTS.
• Video Overview: https://youtu.be/lF4dUHr3fMg
• Compatibility Notes:
  • FLIP Fluids 1.8.4 is officially supported in Blender 4.1 to Blender 4.5.
  • Blender 5.0: At this moment there are no known compatibility issues specific to Blender 5.0 Alpha, but this could change as Blender 5.0 develops (Blender 5.0 Support).
• Added: Alembic import/export changes and improvements:
  • The FLIP Fluids sidebar > Command Line Tools > Alembic Export Tool has moved to the Blender > Export > FLIP Fluids Alembic (.abc) operator.
  • Added a Blender > Import > FLIP Fluids Alembic (.abc) operator to automate importing a FLIP Fluids Alembic simulation. This operator will automatically set up the Alembic import with the addon geometry node modifiers and transfer any exported velocity/color attributes for rendering.
  • Added a workaround to Blender issue #99293 where the Alembic exporter would not export color attributes to the .abc file.
  • Future Development: A custom written FLIP Fluids Alembic exporter is currently in development for the next addon version which can export a simulation about 30x - 45x faster compared to Blender's exporter while using less RAM and reducing export filesizes.
• Added: Operators to the Add Objects (Shift+A) context menu:
  • The FLIP Fluids sidebar > Add/Remove Objects operators have been copied to the Add Objects > FLIP Fluids menu.
  • Added operators to generate quick simulation setups for a basic water liquid, a thick viscous liquid that buckles and coils, and a thin viscous paint-like liquid. More quick liquid operators are in development.
• Bug Fix: Fixed poll() error triggered when launching a command line Compositing Tools Passes Render when no render passes are activated.
• Bug Fix: Fixed issue where if a simulation was started with the Domain > Particles > Enable Fluid Particles option disabled, resuming the simulation after enabling this option would not follow the Particle Export Amount setting and always export 100% of the particles.
• Bug Fix: Fixed issue where Min/Max Float properties would not update to clamp their min/max values when changing one of the values.
• Bug Fix: Corrected source file encoding from ISO-8859-1 to UTF-8 (issue #649).
• Bug Fix: Fixed warning alerts on settings containing filepaths in Blender 4.5+ (issue #647 comment).
• Bug Fix: Fixed Invalid operator call Blender warning that could be triggered during render when the FLIP Fluids sidebar > Auto-load baked frames and Sync with CMD options were both enabled.
• Bug Fix: Fixed error that could be triggered by opening MacOS/Linux filepaths on Windows.
• Bug Fix: Fixed baking error that could be triggered if the Color and Mixing Attributes > Mix Rate value was set to 0.
• Bug Fix: Removed stray debug print statements from the Blender console.
• Bug Fix: Fixed issue where Help > FLIP Fluids > Copy System & Blend Info operator would not find enabled addons in Blender 4.2+.
• Bug Fix: Fixed issue where the FLIP domain could be unnecessarily updated to the current FLIP Fluids version when the domain was already created in that version.
• Change/Improvement: Updates to built-in geometry node modifier:
  • For the most up-to-date additions to the FLIP Fluids geometry node modifiers, create a new Blend file in this version.
  • Geometry node modifiers have been renamed from FF_MotionBlur... modifiers to FF_GeometryNodes... as these node groups have grown to handle more than just motion blur. The simulation meshes will automatically be updated to use these new modifier names upon loading a Blend file.
  • Geometry node groups generated by the addon now contain a warning message not to edit the node group to help avoid having custom edits overwritten. Instead, users should create customizations by adding a new geometry node modifier to the stack. Alternatively, duplicating the modifier and making edits to this can also work.
  • Organized geometry node modifier inputs into panels for more recent versions of Blender. More UI improvements to geometry node modifiers will be added as the minimum Blender version requirement is raised in future development.
  • Added FF_GeometryNodes... modifier option to shade smooth/flat the fluid surface, fluid particle instances, and whitewater instances. This change avoids a bug in Blender that could turn off smooth shading during playback or when using default Blender render operators.
• Change/Improvement: Updates to FLIP Fluids sidebar > Command Line Tools operators:
  • Linux command line support improvements. Removed requirement for bash terminal, improved shell escaping when using command line operators (pull #650).
  • The Command Line Tools > Bake > Render During Bake feature not supports Compositing Tools Passes Rendering.
  • The Command Line Tools > Render > Multi Instance render features will now implement a continuous frame sequence optimization when multiple frames are in the render queue instead of re-launching Blender between each frame. Note: Only applicable to single Blend file rendering with a single render instance and single frame steps.
  • The Command Line Tools > Render Frame operator will now default to rendering a PNG image if an video format is selected instead of producing an error popup.
  • Command line operators will now write scripts to the cache_directory/scripts directory instead of next to the Blend file to avoid clutter. If the user is only using the render operators and does not have a FLIP domain, the scripts will be stored in a flip_fluids_addon_scripts directory.
  • Command line render Normal mode now supports the Skip rendered frames option.
  • All .bat/.sh scripts generated by the command line render operators can now be re-run directly and will continue from any unrendered frames if the Skip rendered frames option is enabled. Running the scripts directly avoids having to open the Blend file before launching/continuing the render.
• Change/Improvement: Updated the Domain > Advanced > Max Substeps setting to use a soft max of 100 instead of a hard max so that the user can set a higher value if needed. Note: Outside of extreme circumstances, this setting should not require a value close to or above this soft max.
• Change/Improvement: Color and Mixing Attributes > Mix Rate value is now taken into account when computing adaptive substeps. The default value will often only require 1 substep, but higher color mix rates may require more substeps to fulfill the amount of mixing.
• Change/Improvement: The Help > FLIP Fluids > Copy System & Blend Info operator now replaces the system username in filepaths with a generic 'username'.
• Change/Improvement: Newly initialized FLIP simulation meshes will now enable the Obstacle Properties > Cycles Motion Blur option based on if other simulation meshes have this option already enabled. This change avoids the issue of meshes not rendering with motion blur if the user initialized motion blur before initializing all simulation meshes.
• Change/Improvement: Dates in the addon UI and product files are now formatted according to the ISO 8601 standard (YYYY-MM-DD) to simplify date scripting and filesystem sorting.
• Removed: Color and Mixing Attributes > Mixing Radius setting has been removed. This setting is no longer needed as increasing this value is effectively a less performant version of increasing the Mix Rate value.
• Removed: FLIP Fluids Preferences > Show Documentation Links in UI feature. This feature became out of date and was not often used.
• UI: Updated Blender Market links to Superhive as part of the marketplace rebranding (read more about Superhive).
• UI: The FLIP Object > Export Animated Mesh option is now copied to the Fluid/Inflow > Export Animated Target option if the target object is an animatable FLIP object.
• UI: Fixed misc tooltip typos. Thanks for the reports!
• Documentation: A Blender and addon version compatibility table has been added here: Release Notes > Version Compatibility Table.
• Building/Compiling: Changes have been made to how the FLIP Fluids addon and simulation engine is built/compiled (See updated build instructions). Notes:
  • Added Alembic and Imath dependencies as part of developing a custom Alembic exporter. Ensure that these are built/installed prior to building this project.
  • Compilers now require full C++17 support (previously C++11).
  • Due to build changes and to avoid conflict when overwriting an addon installation, the fluid engine library and directories has been renamed from pyfluid to ffengine.
  • Building the addon using the automated build.py script will now package the addon as an installation zip archive (pull #653).
  • CMakeLists.txt file is now located at the project root to simplify building.
  • Removed requirement for building debug version of the fluid simulation library. The debug version has been used less over past few years of development as the simulation engine has become more stable. By default, the library will only be built and distributed in release mode.
  • Corrected cmake_minimum_required() deprecation warning for newer versions of CMake.
  • Suppressed misc false-positive compiler warnings for GCC/Clang.

• FLIP Fluids 1.8.7 includes new geometry node features, bug fixes, improvements, and official Blender 5.2 LTS support.
• Compatibility Notes:
  • FLIP Fluids 1.8.7 is officially supported in Blender 4.5 to Blender 5.2.
  • For best compatibility, latest bug fixes, and full feature set, Blender 5.2 is recommended.
  • Blender 5.3: At this moment there are no known compatibility issues specific to Blender 5.3 Alpha, but this could change as Blender 5.3 develops (Blender 5.3 Support).
• Added: Implemented cache loading optimizations. Playback is now 3x - 9x faster, with higher performance gains for larger amounts of geometry.
• Added: FLIP Outflow > Gradual Outflow options to gradually remove fluid from an outflow as an alternative to immediately removing and fluid that enters the outflow.
• Added: A 3D UVW texture coordinate attribute to the fluid surface and fluid particles. This attribute stores initial particle UVW coordinates at the time that the fluid particles is spawned. This attribute can be accessed within an Attribute Node with the name flip_uvw from the Vector output. Can be used for basic texture projection effects.
• Added: FF_GeometryNodesFluidParticles features for filtering particles based on attribute values. Modifier contains settings to:
  • Delete particles outside of a Min/Max Velocity, Speed, and Vorticity Range, or outside of a color tolerance.
  • Scale particles towards a scale factor when near the Min/Max attribute range or as color reaches maximum tolerance.
  • Store the Min/Max range or color tolerance mapped to a [0, 1] attribute to be used in a shader or other geometry node modifiers.
• Added: FF_GeometryNodesFluidParticles instancing feature to instance a separate object based on Source ID attribute. Supports Source ID attribute values from 0 to 8.
• Added: FLIP Fluids USD Export > Incremental Save option in Blender 5.2+ to write the export file after exporting a specified number of frames to fix a memory usage issue during export (Issue #156402).
• Improvement: The Command Line Tools > Render After Bake feature will now run the bake and render process within the same terminal window instead of opening a new window when the render begins.
• Improvement: The command line renders will display the Blend filepath between frames to improve visibility of which command line process is being run.
• Improvement: The Command Line Tools operators will now launch terminals with a window title display the process and Blend file name.
• Improvement: The simulation baking console output and logging will now display the Blend filepath between frames.
• Improvement: Custom Domain > Debug drawing now displays with antialiasing in Blender 5.1+.
• Improvement: FF_GeometryNodes features will no longer take effect if the required attribute does not exist.
• Improvement: Reduced render memory usage when motion blur is disabled or the flip_velocity attribute does not exist.
• Improvement: FF_GeometryNodes instancing features will now inherit smooth/flat shading the instance object when the Shade Smooth Instances option is disabled.
• Bug Fix: Fixed memory limitations that would trigger std::length baking errors when running simulations with too large of a resolution or when simulating too many fluid or whitewater particles. There is now no limit to how heavy of a simulation can be run, other than hardware or time limits.
• Bug Fix: Fixed baking error if an object contains an uninitialized geometry nodes modifier with no set node group (Issue #667).
• Bug Fix: Fixed error that could be triggered during render, resulting in an incomplete render setup.
• Bug Fix: Fixed that could be triggered when installing an existing preset library location.
• Bug Fix: Fixed DivideByZero errors that could be triggered when operating on a domain that had not been fully initialized.
• Bug Fix: Various operator errors that could be triggered in the Cycles addon was not enabled.
• Bug Fix: Fixed issue where FLIP Force Field > Gravity Scale may not be computed correctly outside of the gravity scale width or max distance of the force field.
• Bug Fix: Fixed issue where FLIP Force Field > Gravity Scale was not being computed correctly inside of a volume force, resulting in fluid not matching the volume force shape closely enough.
• Bug Fix: Fixed USD export/import compatibility issues and format consistency between Blender 4.5 - 5.2.
• Bug Fix: Removed stray debug printouts to the Blender console.
• Bug Fix: Fixed deprecation warnings due to different Python versions between Blender 4.5 - 5.2.
• Bug Fix: Fixed string literal SyntaxWarning that could be triggered during save depending on CPU model name.
• Bug Fix: Fixed bug where Domain > Debug > Display Grid > X and Z Offset values were swapped when controlling grid offsets.
• Bug Fix: Fixed issue where UI material lists were displayed in reverse order. Added material categories to separate between FLIP FLuids Material Library and scene materials.
• Bug Fix: Fixed Compositing Tools issue where particles could not be scaled higher than 1.0.
• Bug Fix: Fixed issue where FF_GeometryNodes modifiers could display irrelevant settings for selected menus in Blender 5.1+.
• Bug Fix: Fixed issue where FLIP Domain update routines were not being run on a depsgraph update in Blender 5.1+.
• Bug Fix: Fixed logging bug that would log setting the Max Whitewater Particles value for every frame if the value was set to 0.
• Bug Fix: Fixed issue where some FF_GeometryNodes modifier keyframes would not take effect in the render.
• Bug Fix: Fixed issue where fluid particle or whitewater meshes may display empty geometry if multiple FF_GeometryNodes modifiers were chained together in the modifier stack or when 'cloning' the simulation mesh through an Object Info node.
• Bug Fix: Fixed <-Wmaybe-uninitialized> warnings during compile in newer versions of GCC.
• UI: Command Line Tools operators will now display an error popup if a Blend file save error is encountered such as permission or resource packing errors.
• UI: Various tooltip corrections.
• Example Scenes and Presets: Blend files and assets have been improved and updated for newer versions of FLIP Fluids and Blender.

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-186-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: https://youtu.be/3KDoTrQ4DhI
• 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.

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-185-nov-18-2025

• FLIP Fluids 1.8.5 includes many improvements, geometry node features, a variable density solver, bug fixes, and official compatibility support for Blender 5.0.
• Video Overview: https://youtu.be/3XghoDDRwbc
• Compatibility Notes:
  • FLIP Fluids 1.8.5 is officially supported in Blender 4.5 to Blender 5.1.
  • Blender 5.1: At this moment there are no known compatibility issues specific to Blender 5.1 Alpha, but this could change as Blender 5.1 develops (Blender 5.1 Support).
• Added: Variable density solver feature to Domain > World panel for mixed density liquids that float or sink (Documentation).
  • After enabling, each Fluid/Inflow object can be set to assign a density value to the generated fluid.
  • After baking, the density attribute values can be accessed from an Attribute Node with the name flip_density from the Fac output.
  • Tip: Rendering fluid particles shaded or hidden based on density can be useful for visualizing variable density simulations.
• Added: Various geometry node features for customizing the fluid surface, fluid particles, and whitewater simulation meshes (Documentation).
  • These features can be found in the FF_GeometryNodes modifier on the fluid surface, particles, and whitewater simulation meshes.
  • New Fluid Surface Modifier Features:
    • Motion Blur > Apply Simulation Time/World Scale - Automatically scale motion blur according to the baked simulation time and/or world scale for consistent screenspace motion blur. If applying simulation time scale to motion blur, you will no longer need to manually animate motion blur scale with the time scale for slowmotion effects. This feature will only take effect if the simulation was baked in the current addon version or later.
    • Meshing > Shade Smooth - Option to specify whether to smooth shade or flat shade the mesh.
    • Meshing > Remove Mesh Near Domain Boundary - Options to remove parts of the mesh near the domain boundary to create a surface-only mesh. Contains options to enable or disable ±X/Y/Z sides of the domain and distance from the domain boundary. This feature works similar to the Domain > Simulation > Meshing Against Boundary feature except that the result is not baked into the mesh and can be applied after the simulation.
    • Meshing > Flatten Mesh Near Domain Boundary - Options to flatten the surface mesh towards a water level near the edges of the domain boundary. Useful for compositing or combining the surface mesh into a larger ocean plane.
      • Feature should be used in combination with the Remove Mesh Near Domain Boundary feature, using geometry nodes or domain settings.
      • Water level can be specified using a Z value or the Z coordinates of an object.
      • Flattened Width - Width of the flattened edge at the domain boundary.
      • Transition Width - Width of the smoothed flattening transition.
      • Store Displacement Attribute - Store amount of applied Z displacement as a flip_displacement named attribute. Enabling is required for matching displacement in the whitewater and fluid particle simulation meshes.
      • Store Transition Mask Attribute - Store transition mask as a flip_transition_mask named attributes. Values are in the range [0.0, 1.0] where 0.0 is fully flattened and 1.0 is no flattening. Useful for fading out the edges of the fluid surface in a shader.
  • New Fluid Particle and Whitewater Modifier Features. The following features are supported on both the fluid particle and whitewater meshes.
    • Material > Apply Material - Option whether to apply the specified material to the particles. Disable to inherit material from instances if object instancing is used.
    • Motion Blur > Apply Simulation Time/World Scale - Same as modifier settings on fluid surface.
    • Particle > Particle Display Mode - Settings for how to display and render the particles.
      • None - Display the particles as raw vertices.
      • Point Cloud - Display the particles as a Point Cloud type object. This is the most performant method to render and display particles in Blender.
      • Instancing - Display the particles with object instances. This is the least performant method to render and display particles in Blender, but offers more customizations over the shape. Try to limit the amount of particles rendered using this method to avoid performance issues.
    • Point Cloud and Instancing Options:
      • Particle Scale - Object scale of particles in Blender Units.
      • Particle Scale Multiplier - Multiply particle scale by this value. Useful for precision scaling for small particle sizes.
      • Particle Scale Random - Amount of linear randomized particle scaling.
      • Random Bias - Random bias of particle scaling distribution. Values less than 1.0, bias towards small particles. Values greater than 1.0, bias towards large particles. Value equal to 1.0, no bias.
    • Particle Instancing Options:
      • Instancing Mode
        • Icosphere - Instance icosphere objects over the particles.
        • Object - Set a custom object to instance over the particles.
        • Collection - Randomly instance objects from a collection over the particles.
      • Randomize Instance Rotation - Apply a random rotation for each particle instance.
      • Align Instance to Velocity - Align instance Z axis to the particle velocity vector. Requires enabling the FLIP Velocity attribute before baking.
      • Shade Smooth Instances - Option to specify whether to smooth shade or flat shade the instance objects.
      • Realize Instances - Convert particle instances to mesh geometry. Required for transferring simulation or custom attributes the particle geometry. This option can generate a large amount of geometry and result in performance issues for large amounts of particles or for high geometry instances.
    • Displace > Match Flattened Surface Displacement - If the Surface Modifier > Flatten Mesh Near Domain Boundary option is enabled, apply the same displacement to the particle Z level.
    • Lifetime Based Particle Scaling - Scale particles at the end of their lifetime. Requires enabling the FLIP Lifetime attribute before baking.
      • Final Scale Factor - Particle scale factor at the end of the particle lifetime.
      • Scaling Duration - Duration of the scaling transition in simulation seconds.
      • Lifetime Offset - Time offset for when the scaling transition begins.
      • Store Lifetime Scaling Transition Attribute - Store transition values as a flip_lifetime_transition named attribute. Values are in range [0.0, 1.0], starting at 0.0 before scaling transition begins and ending at 1.0 when scaling transition is complete. Useful for shading the particles based on scaling transition.
  • New Fluid Particle Modifier Features. The following features are only supported on the fluid particle meshes.
    • Age Based Particle Scaling - Scale particles at the beginning of their age. Requires enabling the FLIP Age attribute before baking.
      • Starting Scale Factor - Particle scale factor at the start of the particle age.
      • Scaling Duration - Duration of the scaling transition in simulation seconds.
      • Age Offset - Time offset for when the scaling transition begins.
      • Store Age Scaling Transition Attribute - Store transition values as a flip_age_transition named attribute. Values are in range [0.0, 1.0], starting at 0.0 before scaling transition begins and ending at 1.0 when scaling transition is complete. Useful for shading the particles based on scaling transition.
    • Filter Particles by Source ID - Show or hide particles based on Source ID attribute. Requires enabling the FLIP Source ID attribute. Useful for selectively rendering particles based on the Fluid/Inflow object that they are emitted from.
      • Contains checkbox options from 0 to 8 to control whether to show or hide particles with the corresponding Source ID. For example, disabling checkbox 2 will hide particles with Source ID = 2.
  • Added FLIP Fluids Sidebar > Geometry Node Tools > Update Geometry Node Modifiers operator to update the fluid surface, fluid particle, and whitewater geometry node modifiers to the current addon version.
    • Operator will transfer older modifier settings to the updated modifier where possible to closely match the previous result.
    • Operator will not delete existing FF_GeometryNode modifiers or datablocks to avoid data loss. Existing modifier will be renamed with a BACKUP prefix and disabled from the modifier stack. This backup can be removed when no longer needed.
• Bug Fix: Fixed issues related to the File > Export/Import > FLIP Fluids Alembic (.abc) operators.
  • Fixed issue where exporter setup for fluid particle or whitewater may not be recognized by Blender's Alembic Exporter as animated meshes due to not containing any modifiers.
  • Fixed issue where exporter may not apply the fluid surface smooth modifier.
  • Fixed issue where exporter would continue simulation export when the simulation cache does not exist, resulting in an empty Alembic file.
  • Fixed issue where exporter would not export velocity attribute when meshes contained certain versions of the FF_GeometryNodes modifier.
  • Fixed export issue where simulation meshes would not be exported if the outliner render visibility was disabled.
  • Fixed issue where importer could unexpectedly set motion blur velocity attribute to (0, 0, 0) depending on export configuration.
  • Fixed issue where imported Alembic mesh may not be animated if the first frame did not contain geometry.
  • Fixed import issue where the FF_GeometryNodes modifier on Alembic meshes would contain features that were not supported due to unsupported/missing attribute or feature that require addon scripting.
• Bug Fix: Fixed warning messages related to deprecated bgl (OpenGL Wrapper) calls in Blender 5.0.
• Bug Fix: Fixed bugs related to EEVEE render engine name change in Blender 4.5 and later.
• Bug Fix: Fixed FF_GeometryNodes warning when setting material on invalid geometry.
• Bug Fix: Fixed issue where some keyframed FF_GeometryNodes modifier values would not take effect in the render (related to issue #71908). All keyframeable modifier values are now supported.
• Bug Fix: Fixed issue where an older Blend file compatibility update could trigger an error, resulting in a missing FF\GeometryNodes_ modifier on the fluid surface.
• Bug Fix: FLIP Fluids Sidebar > Initialize Motion Blur operator now only switches the render engine to Cycles when the current render engine is set to a renderer that does not support custom motion blur (EEVEE or Workbench) to avoid switching away from third-party renderers.
• Bug Fix: Added missing GPL license to command line operator scripts.
• Bug Fix: Fixed issue where a Point Cloud type object could be set as a FLIP type object, resulting in baking errors. A popup error will be displayed to notify the user that Point Cloud objects are not supported as FLIP objects.
• Bug Fix: Fixed 'RuntimeError: Error: KeyMapItem not found in KeyMap 3D View' error during addon unregistration that could be triggered if the keymap was unavailable.
• Bug Fix: Improved addon startup/registration performance by removing older and unused Blender 2.79 compatibility code.
• Bug Fix: Fixed issue where some fluid surface attributes (age, lifetime, whitewater proximity, viscosity, color) were offset by half of a voxel.
• Bug Fix: Fixed issue where Domain > Advanced > Simulation and Particle Stability > Viscosity Solver Max Iterations would be applied to the pressure solver instead of the viscosity solver.
• Bug Fix: Fixed baking errors due to deprecated and removed Animation & Rigging Python API calls in Blender 5.0.
• Bug Fix: Fixed bug where FLIP Lifetime attribute data could contain values less than the expected minimum value (ex: negative values).
• Bug Fix: Removed unsupported API call to depsgraph update during frame change. This call was required for render stability in earlier versions of Blender, but caused stability issues in newer versions of Blender.
• Bug Fix: Fixed issue where force field gravity scale would not be computed outside of the force field max distance bounds, resulting in incorrect gravity scale and box shaped artifacts when combining multiple force fields.
• Bug Fix: Fixed issue where object delta transforms were not applied to keyframed FLIP objects within the simulation.
• Bug Fix: Fixed issue where FLIP Fluids Sidebar > Compositing Tools would render the shadowcatcher pass by default.
• Bug Fix: Removed stray debugging console outputs during Blender shutdown.
• Bug Fix: Fixed error that would prevent Shift + A > FLIP Fluids > Quick Liquid operators from completing when the addon version does not contain built-in materials.
• Bug Fix: Fixed UnboundLocalError that could be triggered during render due to operating on an invalid simulation mesh object types.
• Bug Fix: Fixed issue where some presets assets contained an orphaned mesh data block that would result in an unrelated object to be imported from the asset library into the Blend file.
• Change: Default values for fluid particle viewport preview display are now set to the same value to avoid flickering during Surface/Boundary/Interior particle type transitions.
• UI: Updated collapsible panel UI elements to used modern Blender UI features.
• UI: Improved wording on 'Missing geometry nodes modifier' warning to direct the user to click the operator to resolve the issue.
• UI: Corrected FF_GeometryNodesFluidParticle > Particle Scale tooltip that contained text for another parameter.
• UI: Added a copy of the Domain > World > Global Force Field Weights to the FLIP Force Field object menu for convenience.
• UI: Fixed inconsistent capitalization of Skip Re-export option across the addon UI.
• UI: Updated Twitter labels to X (Twitter).
• Building/Compiling:
  • CMake: Removed building a standalone Alembic export executable. This feature is now built as a shared library.
  • CMake: Fixed MacOS RPATH configuration that prevented Alembic dependencies from being found.
  • CMake: Source files are no longer collected via CMake GLOB and are instead specified explicitly to avoid re-build errors. If adding source files, remember to add the file to the CMakeLists.txt sources list.
  • CMake: Corrected publicly linked libraries to private.
  • build.py: Removed build script option flags to supply Alembic and/or Imath dependency filepaths.
  • build.py: Script can now be supplied with a list of dependency filepaths to package within the addon with the -package-dependencies flag.
  • C++: Removed header include guards and replaced with #pragma once preprocessor directive.
  • Python: All compatibility code related to Blender 4.4 and earlier has been removed to simplify the code base.
  • Python: Increased minimum version compatibility to Blender 4.5.0 in blender_manifest.toml

Release Notes: https://github.com/rlguy/Blender-FLIP-Fluids/wiki/Release-Notes#version-184-jul-17-2025

• FLIP Fluids 1.8.4 adds a hotfix to correct a severe bug in the recent FLIP Fluids 1.8.4 (2025-07-14) release that can result in frequent render crashes and can prevent materials from being applied to the simulation. If you have installed the recent FLIP Fluids 1.8.4 release, please update to this new version and restart Blender.
• Compatibility Notes:
  • FLIP Fluids 1.8.4 is officially supported in Blender 4.1 to Blender 4.5.
• Bug Fix: Fixed bug that could result in frequent render crashes and prevent applying materials when applying workaround for issue #71908.
• Bug Fix: Fixed UI bug where the Command Line Tools > Bake > Render After Bake menu could be missing a Skip rendered frames option.

• FLIP Fluids 1.8.4 includes many improvements, smaller features, and bug fixes, as well as official compatibility support for Blender 4.5 LTS.
• Video Overview: https://youtu.be/lF4dUHr3fMg
• Compatibility Notes:
  • FLIP Fluids 1.8.4 is officially supported in Blender 4.1 to Blender 4.5.
  • Blender 5.0: At this moment there are no known compatibility issues specific to Blender 5.0 Alpha, but this could change as Blender 5.0 develops (Blender 5.0 Support).
• Added: Alembic import/export changes and improvements:
  • The FLIP Fluids sidebar > Command Line Tools > Alembic Export Tool has moved to the Blender > Export > FLIP Fluids Alembic (.abc) operator.
  • Added a Blender > Import > FLIP Fluids Alembic (.abc) operator to automate importing a FLIP Fluids Alembic simulation. This operator will automatically set up the Alembic import with the addon geometry node modifiers and transfer any exported velocity/color attributes for rendering.
  • Added a workaround to Blender issue #99293 where the Alembic exporter would not export color attributes to the .abc file.
  • Future Development: A custom written FLIP Fluids Alembic exporter is currently in development for the next addon version which can export a simulation about 30x - 45x faster compared to Blender's exporter while using less RAM and reducing export filesizes.
• Added: Operators to the Add Objects (Shift+A) context menu:
  • The FLIP Fluids sidebar > Add/Remove Objects operators have been copied to the Add Objects > FLIP Fluids menu.
  • Added operators to generate quick simulation setups for a basic water liquid, a thick viscous liquid that buckles and coils, and a thin viscous paint-like liquid. More quick liquid operators are in development.
• Bug Fix: Fixed poll() error triggered when launching a command line Compositing Tools Passes Render when no render passes are activated.
• Bug Fix: Fixed issue where if a simulation was started with the Domain > Particles > Enable Fluid Particles option disabled, resuming the simulation after enabling this option would not follow the Particle Export Amount setting and always export 100% of the particles.
• Bug Fix: Fixed issue where Min/Max Float properties would not update to clamp their min/max values when changing one of the values.
• Bug Fix: Corrected source file encoding from ISO-8859-1 to UTF-8 (issue #649).
• Bug Fix: Fixed warning alerts on settings containing filepaths in Blender 4.5+ (issue #647 comment).
• Bug Fix: Fixed Invalid operator call Blender warning that could be triggered during render when the FLIP Fluids sidebar > Auto-load baked frames and Sync with CMD options were both enabled.
• Bug Fix: Fixed error that could be triggered by opening MacOS/Linux filepaths on Windows.
• Bug Fix: Fixed baking error that could be triggered if the Color and Mixing Attributes > Mix Rate value was set to 0.
• Bug Fix: Removed stray debug print statements from the Blender console.
• Bug Fix: Fixed issue where Help > FLIP Fluids > Copy System & Blend Info operator would not find enabled addons in Blender 4.2+.
• Bug Fix: Fixed issue where the FLIP domain could be unnecessarily updated to the current FLIP Fluids version when the domain was already created in that version.
• Change/Improvement: Updates to built-in geometry node modifier:
  • For the most up-to-date additions to the FLIP Fluids geometry node modifiers, create a new Blend file in this version.
  • Geometry node modifiers have been renamed from FF_MotionBlur... modifiers to FF_GeometryNodes... as these node groups have grown to handle more than just motion blur. The simulation meshes will automatically be updated to use these new modifier names upon loading a Blend file.
  • Geometry node groups generated by the addon now contain a warning message not to edit the node group to help avoid having custom edits overwritten. Instead, users should create customizations by adding a new geometry node modifier to the stack. Alternatively, duplicating the modifier and making edits to this can also work.
  • Organized geometry node modifier inputs into panels for more recent versions of Blender. More UI improvements to geometry node modifiers will be added as the minimum Blender version requirement is raised in future development.
  • Added FF_GeometryNodes... modifier option to shade smooth/flat the fluid surface, fluid particle instances, and whitewater instances. This change avoids a bug in Blender that could turn off smooth shading during playback or when using default Blender render operators.
• Change/Improvement: Updates to FLIP Fluids sidebar > Command Line Tools operators:
  • Linux command line support improvements. Removed requirement for bash terminal, improved shell escaping when using command line operators (pull #650).
  • The Command Line Tools > Bake > Render During Bake feature not supports Compositing Tools Passes Rendering.
  • The Command Line Tools > Render > Multi Instance render features will now implement a continuous frame sequence optimization when multiple frames are in the render queue instead of re-launching Blender between each frame. Note: Only applicable to single Blend file rendering with a single render instance and single frame steps.
  • The Command Line Tools > Render Frame operator will now default to rendering a PNG image if an video format is selected instead of producing an error popup.
  • Command line operators will now write scripts to the cache_directory/scripts directory instead of next to the Blend file to avoid clutter. If the user is only using the render operators and does not have a FLIP domain, the scripts will be stored in a flip_fluids_addon_scripts directory.
  • Command line render Normal mode now supports the Skip rendered frames option.
  • All .bat/.sh scripts generated by the command line render operators can now be re-run directly and will continue from any unrendered frames if the Skip rendered frames option is enabled. Running the scripts directly avoids having to open the Blend file before launching/continuing the render.
• Change/Improvement: Updated the Domain > Advanced > Max Substeps setting to use a soft max of 100 instead of a hard max so that the user can set a higher value if needed. Note: Outside of extreme circumstances, this setting should not require a value close to or above this soft max.
• Change/Improvement: Color and Mixing Attributes > Mix Rate value is now taken into account when computing adaptive substeps. The default value will often only require 1 substep, but higher color mix rates may require more substeps to fulfill the amount of mixing.
• Change/Improvement: The Help > FLIP Fluids > Copy System & Blend Info operator now replaces the system username in filepaths with a generic 'username'.
• Change/Improvement: Newly initialized FLIP simulation meshes will now enable the Obstacle Properties > Cycles Motion Blur option based on if other simulation meshes have this option already enabled. This change avoids the issue of meshes not rendering with motion blur if the user initialized motion blur before initializing all simulation meshes.
• Change/Improvement: Dates in the addon UI and product files are now formatted according to the ISO 8601 standard (YYYY-MM-DD) to simplify date scripting and filesystem sorting.
• Removed: Color and Mixing Attributes > Mixing Radius setting has been removed. This setting is no longer needed as increasing this value is effectively a less performant version of increasing the Mix Rate value.
• Removed: FLIP Fluids Preferences > Show Documentation Links in UI feature. This feature became out of date and was not often used.
• UI: Updated Blender Market links to Superhive as part of the marketplace rebranding (read more about Superhive).
• UI: The FLIP Object > Export Animated Mesh option is now copied to the Fluid/Inflow > Export Animated Target option if the target object is an animatable FLIP object.
• UI: Fixed misc tooltip typos. Thanks for the reports!
• Documentation: A Blender and addon version compatibility table has been added here: Release Notes > Version Compatibility Table.
• Building/Compiling: Changes have been made to how the FLIP Fluids addon and simulation engine is built/compiled (See updated build instructions). Notes:
  • Added Alembic and Imath dependencies as part of developing a custom Alembic exporter. Ensure that these are built/installed prior to building this project.
  • Compilers now require full C++17 support (previously C++11).
  • Due to build changes and to avoid conflict when overwriting an addon installation, the fluid engine library and directories has been renamed from pyfluid to ffengine.
  • Building the addon using the automated build.py script will now package the addon as an installation zip archive (pull #653).
  • CMakeLists.txt file is now located at the project root to simplify building.
  • Removed requirement for building debug version of the fluid simulation library. The debug version has been used less over past few years of development as the simulation engine has become more stable. By default, the library will only be built and distributed in release mode.
  • Corrected cmake_minimum_required() deprecation warning for newer versions of CMake.
  • Suppressed misc false-positive compiler warnings for GCC/Clang.