Fumaris 1.3.0 — October 2026

New

- Air Margin. Simulates a set distance of clear air on every side of the smoke and reaches further in the direction the smoke is moving. It removes the horizontal steps that fast smoke could leave at the edge of the simulated region and gives large plumes the surrounding air they need to roll up. 0.5 m by default; find it below Sparse Block Capacity.

- Large plumes roll up. The pressure solve now reaches across large plumes, so mushroom caps and big rolling shapes form at high resolution and low Sub-Steps.

- Move With Object. A domain can simulate in its own object's space: parent it to a vehicle, or animate it, and the simulation travels and turns with it. Emitters and colliders that ride along stay put in the simulation grid, which keeps fast vehicles smooth with far fewer Sub-Steps. The air stays still in the scene, so smoke trails behind as it would outdoors; Carry Air carries it along instead, as inside a closed cabin. Bakes are written in scene space as before. Not available with Upres.

- Fast emitters and colliders stay stable. Very fast emitters and colliders with few Sub-Steps no longer make the motion explode: vorticity can still sharpen swirls but cannot feed on itself. Fast emitters leave a continuous trail instead of separate stamps, and colliders at rest (a long road, a wall) no longer reserve simulation space along their whole length.

- Fewer switches. Adaptive Boundary Padding is removed; Air Margin replaces it. Allocate Neighbor Blocks, Boundary-Safe Advection and Speed Minimum Smoke are removed: the solver always behaves as it did with them at their recommended values.

- Small Sparse Blocks is off by default. Standard blocks measured about 20% faster for the same GPU memory. The setting stays under Advanced; a domain that never changed it now uses standard blocks, and Sparse Block Capacity means the same amount of space either way.

- A shorter Advanced section: Simulation Speed, Small Sparse Blocks, Auto Cell Size, Convex Collision, Block Minimum Lifetime and the two allocation thresholds. Air Margin and Move With Object are beside Resolution.

- Dissipation accepts typed values above 1 for dense smoke that must clear quickly.

- Source operations. Smoke, Temperature, Fuel and Burn each choose how an emitter writes them: Blend (the existing behavior), Add, Maximum or Replace. Find them beside each rate under Channel Coupling.

- Field masks for effectors. Limit any force by the simulated Smoke, Temperature, Fuel, Burn or Speed, with an Invert option. Turbulence that only breaks up the flame, or only stirs thin smoke, is now one setting.

- Scene Occlusion. The live preview hides smoke behind solid objects using the viewport depth. On by default; switch it off in Preview Settings.

- OpenVDB sources. Map grid names from other tools, read Fuel and Burn grids, play numbered file sequences with a frame offset, and optionally emit the file's velocity grid. A Fumaris bake can be fed back in as a source: its velocity grid is now placed correctly and keeps its real speed.

Fixes

- Empty frames in valid OpenVDB source sequences no longer abort a bake; emission resumes when the sequence contains data again.

- Changing Move With Object during preview restarts the simulation cleanly instead of shifting existing smoke.

- Scene Occlusion refreshes reliably after moving a viewport object, including while preview is paused.

- Baked VDBs are positioned exactly where the simulation is. Earlier versions wrote every grid half a voxel toward -X, -Y and -Z, so a bake sat slightly off its emitters, colliders and the live preview. Re-baking shifts the result by that half voxel; existing caches are not changed.

- Delete, Bake and cache migration touch only numbered Fumaris frame files. Other VDBs sharing the output prefix in the Output Directory are left alone, and folders containing [ ] * or ? work.

- A bake that runs out of disk space stops with an error instead of publishing truncated VDB frames.

- Stopping a bake no longer leaves the interrupted frame behind as a .tmp file.

- A Collection Mesh source no longer fails when one member has no faces.

- Importing a bake on Windows no longer fails when the cache is on another drive.

- A duplicated simulation no longer takes over the original's cache.

- When Sparse Block Capacity is full, a newly active emitter now gets blocks ahead of empty blocks that were only waiting out Block Minimum Lifetime.

- Baked velocity grids no longer contain stray values when Small Sparse Blocks is on (the default before 1.3.0). Parts of the velocity field were being overwritten with unrelated data from neighboring blocks, differently on each run and graphics card, which could streak motion blur and distorted bakes fed back in as VDB sources. Re-bake to get correct velocity.

Performance

- Faster per-frame export for particle, Collection Mesh, deforming, masked and Geometry Nodes mesh emitters; faster VDB conversion and VDB-source loading.

- Static meshes are uploaded once when a simulation starts on frame 0.

Scenes from earlier versions simulate differently in 1.3.0. The solver now always takes its best path instead of offering it as an option: edges are cleaner, large plumes roll up, and more sparse blocks are in use (Air Margin is 0.5 m unless you set it). Check the capacity readout after updating, and re-bake shots that must match across versions before you update mid-project. Scene Occlusion changes only the live preview.

Install the ZIP for your platform through Blender's Install from Disk. Stop simulations and restart Blender after updating. Requires Blender 5.2+. Apple Silicon Mac requires macOS 26+; Intel Macs are not supported.

The four demo scenes are unchanged; use the existing Fumaris 1.2.0 demo ZIP.

Fumaris 1.2.1 Hotfix — October 1, 2026

Fixes:

- Baking no longer fails when the source has no particles or active smoke on an initial frame. Empty frames produce valid VDB files and keep the sequence aligned.

- Small, fast-moving mesh emitters now produce continuous smoke trails across solver substeps instead of disconnected puffs.

Velocity settings and defaults are unchanged. Existing scenes and caches are preserved.

Install the ZIP for your platform through Blender’s Install from Disk. Stop simulations and restart Blender after updating. Requires Blender 5.2+. Apple Silicon Mac requires macOS 26+; Intel Macs are not supported.

The four demo scenes are unchanged; use the existing Fumaris 1.2.0 demo ZIP.

Fumaris 1.2.0

Apple Silicon Mac addition (September 28): native ARM64 download for macOS 26+ and Blender 5.2+, tested on Mac mini M4 with 16 GB unified memory. Bundles MoltenVK for Metal GPU simulation; no separate Vulkan installation needed. Intel Macs are unsupported. Windows/Linux downloads are unchanged.

Quick Setup adds Rising Smoke, Steady Fire and Explosion scenes. Optional Bake on Preview records VDBs during playback and imports them when paused or stopped. On-demand GPU pipeline compilation shortens startup; shared mesh instances export faster. Experimental smoke/fire Upres adds an explicit detail memory limit and visible errors. Playback controls and sparse-capacity guidance are clearer.

The separate demo ZIP contains Explosion, Mushroom, Tornado and Effector Vacuum. Install the extension ZIP matching your operating system through Blender’s Install from Disk, extract the demo ZIP before opening scenes, and restart Blender. Start at reduced resolution on memory-limited systems. Upres and Normal Velocity remain experimental.

- Control live preview without selecting the domain: viewport/timeline header
  controls, participant controls, a scene domain picker, and configurable
  Shift–Alt–Space (play/pause/resume) and Shift–Alt–Backspace (stop) shortcuts.
- Add AgX (Preview) tone mapping and calibrate AgX/Filmic brightness against
  Off (Legacy). These are preview approximations, not Blender's full OCIO transform.
- Remove the obsolete points preview renderer. Volume preview remains;
  Geometry Nodes and Collection Points emitters are unaffected.
- Allow hidden domains to simulate while suppressing their overlay. Explain when
  live preview needs a 3D Viewport instead of failing with a density-readback error.
- Prefer compatible system GCC runtimes for the isolated Linux worker so newer
  graphics drivers can load, retaining the bundled fallback on older systems.
- Explain why Smoke Upres is disabled during running/paused previews. Rename
  effector Radius to Influence Radius to distinguish coverage from detail.
- Default emitter and effector coupling to 8, Expansion Per Burn and Vorticity
  to 2, and temperature/burn exports to enabled. Preview density defaults to 2,
  brightness to 5, and smoke color to (0.5, 0.5, 0.5).
  Existing explicitly stored settings and animation are preserved.
- Resolve unsaved-project cache paths to writable user storage.
- Remove orphaned preview code and update diagnostics and profiling tools.

Stop active jobs and restart Blender after updating the extension and native
worker together. Existing caches are preserved. Native Blender playback remains
independent; use it for baked VDB playback.

Collection Points combines source meshes into one sphere-cloud emitter, with size-based or fixed radii and per-object motion velocity.

Collection Mesh combines evaluated meshes with shared emission settings, nested collection support and reflected winding correction. Source meshes do not need individual Fumaris roles.

Fixed Copy Diagnostics in Blender extension installs and a Linux dependency packaging issue.

Stop jobs and restart Blender after installing the ZIP for your operating system. Keep caches from different versions separate. Blender 5.1+, Windows/Linux x64; main Linux package requires glibc 2.35+.

The included demo is unchanged. See the bundled changelog and documentation for collection mesh limitations.

Previous release. Includes the original 1.0.0 Windows and Linux installers and demo scene.