Settings (Edit → Settings…)

• Display units — the unit (nm / μm / mm) that coordinates, sizes, and step fields are shown and entered in. Stored values stay nanometer-precise regardless.
• Default path width — applied to new paths on commit. 0 keeps paths hairline.
• Default text size — pre-fills the size field when the Text dialog opens.
• Confirm before destructive actions — ask before "New document" discards unsaved work.
• Invert scroll-wheel zoom direction — flips which scroll direction zooms in.

Under Advanced:

• Grid density (target px) — the minor grid tries to stay near this pixel spacing as you zoom. Default 12 px; range 4–64. Smaller values give a denser grid.
• Sub-divide grid before it expands past target spacing — when on, a lighter sub-minor grid appears at 1/5 of the minor step whenever the minor step grows much coarser than the target. Keeps snap points visible at all zooms.
• Hierarchy depth — levels of nested cell references drawn in full; deeper instances render as outlines. −1 = unlimited (full fidelity). A big speed-up on dense IP blocks. Also cycled from the status bar (H).
• Auto-LOD threshold (px) — references whose on-screen bounding box is smaller than this collapse to a single outline regardless of depth. 0 disables auto-LOD.
• Arc / circle max chord deviation — hard ceiling on how far the flattened arc polyline may fall short of the true arc. Smaller = more vertices = smoother curve. 50 nm is a fab-friendly default.
• Min arc segments per quadrant — floor that prevents tiny circles from collapsing to two-vertex polygons even when the deviation budget would allow it.

(Snap tolerance and snap modes live in the toolbar's Snap settings popover; the polar-tracking angle step is set from the POLAR button in the status bar.)