preFlight v1.2.0

Serpentine

Note - Serpentine is not suitable for all geometry and may produce poor or unexpected results on complex shapes. It works best on symmetric objects such as nuts and bolts

• New perimeter generator mode that fills a region with a single continuous extrusion in place of separate perimeters and infill. The path weaves inward from the boundary in a repeating serpentine pattern
  • Turn it on per region under Print Settings > Layers and perimeters > Serpentine. It runs on the Athena generator, so enabling it switches the generator to Athena (with a confirmation prompt)
• Layer ridge stacking: Aligned, Staggered, or Random. Staggered (default) shifts the pattern half a period each layer so the turns overlap each other for a stronger bond between layers
• Depth limit: form a serpentine wall to a set depth in mm and fill the interior with sparse infill and solid top/bottom layers
• Aim: Convergent or Perpendicular, controlling how the depth-limited pattern points at the inner boundary (depth mode only)
• Solid top and bottom layer option prints solid infill with a serpentine band so visible faces stay closed
• Has its own feature type in the G-code preview, with overhanging spans split as "Serp. Overhang"
• Prints at External perimeter speed, fan, and acceleration settings with its own manual fan controls under Filament > Cooling
• Extrusion width, overlap (negative values lower density), and maximum bead width are all configurable

Preprocessing

Important - do not keep your custom preprocessing scripts inside preFlight's resources folder. preFlight ships self-contained, so a script saved there does not carry over when you install a new version. Keep your custom scripts outside of the preFlight install folder to guarantee they survive upgrades.

Previously installed Python packages (numpy, etc.) need to be reinstalled after this update, but will now survive future updates and will only need reinstalling when preFlight ships a new version of Python.

• Installed packages are stored in your preFlight data folder, so upgrading preFlight no longer wipes them
• The Python Console reliably launches preFlight's bundled Python and pip on Windows, macOS, and Linux, with pip pre-installed and HTTPS working out of the box
• Only packages that provide a prebuilt wheel can be installed (the bundled Python has no compiler)

Interlocking

• "Perimeters while Interlocking" perimeter count reduction fills suppressed regions with the full perimeter count while the buried core keeps its reduced walls and interlocking shells (#224)

Narrow-to-Athena

• Narrow-to-Athena infill option now splits a surface by width: thin frames, necks, and spikes convert to a smooth Athena bead while the wider area keeps its solid pattern (#239)
  • Added a separate opt-in for top and bottom surfaces (off by default); internal solid always splits when Narrow-to-Athena is on
  • If the split fails to cover the surface, the region falls back to un-split so no gap is left

Speed & Time Estimation

• Fixed badly inflated time estimates on Klipper and RepRapFirmware profiles, where a small part could read days instead of minutes. Klipper limits are built from the four fields it actually exposes rather than hidden legacy per-axis arrays, RepRapFirmware falls back to Duet firmware defaults, and a zero acceleration limit is read as "no limit" instead of freezing the move (#246)
• Dynamic overhang speed interpolates smoothly between the configured bands instead of stepping between them, and rounds to a 2 mm/s grid to keep the G-code smaller
• Print-level max volumetric flow (renamed from max_volumetric_speed, with the old name kept as an alias) moved into the Print Settings speed group and the sidebar, where it caps each filament's flow under auto speed
• Renamed the dynamic overhang speed labels to "Speed at N% overhang"

Layer Height

• Repeating-decimal layer heights (1/3, 1/6, 1/7, 1/9 mm) resolve to their exact fraction, so past the first layer every N layers add up to exactly 1 mm (3 at 0.3333 mm, 6 at 0.1667) instead of drifting up the object
• Organic supports follow the object's layer grid instead of landing on their own Z at fractional layer heights
• Added N-per-mm guidance and a value cheat sheet to the layer height tooltip

Config Import

• SuperSlicer and other external config bundles that used to fail on import now load: blank extrusion widths fall back to auto, arc_fitting converts from a bool, and host_type "klipper" maps to "moonraker" (#162)
• Importing a bundle from another slicer warns that its settings may not translate exactly

Menus & Right-Click

• Added Export G-code / Slice Platter and view-navigation entries to the Prepare and Preview right-click menus
• Fixed the object-list and preset context menus opening in the top-left corner instead of at the cursor
• Fixed Recent Projects opening the wrong project after the list reordered (#233)
• Fixed object-list setting changes leaving the action button on "Export G-code" and blocking reslices for the rest of the session (#230)
• Stopped the top menus closing themselves on open under seamless window managers such as Qubes (#233)

Bug Fixes

• Fixed Shift+drag box selection on the plate selecting nothing (#230)
• Fixed the support blocker painting nothing on right-click, so supports were never actually blocked
• Fixed Delete removing the object instead of restarting selection while the Measure gizmo is open (#236)
• Fixed right-clicking a brim ear while hovering the object also opening the platter menu
• Fixed a lower-density part of a multipart object losing its infill on layers it shares with a taller part (#235)
• Fixed rendering issues with currency symbols outside the Latin-1 range (ruble, euro, won, rupee)
• Fixed the Preprocessing tab labels being unreadable in light themes on Linux

Hardware

• Added the Bluetooth SpaceMouse Wireless and SpaceMouse Pro Wireless to the 3Dconnexion device list on Linux and macOS (#244)

Developer

• Added a runtime --debug flag (fill, perimeters, interlock, serpentine, or all) that replaces the old compile-time debug switches