oxiDraft

A fast, from-scratch 2D CAD system written in Rust — an exact geometry kernel under a modern, direct-manipulation interface.

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oxiDraft is a 2D CAD drafting environment built entirely from the ground up in Rust — no CAD engine dependencies, no port of an existing kernel. It pairs the precision of a real geometry core with the feel of a modern app: a deep, glass-panelled dark UI, a Ctrl+F command palette, live object snapping, and CAD-style grips on everything you draw.

The kernel works in f64 coordinates with tolerance-based predicates. Lines, circular arcs, elliptical arcs, cubic Béziers, polycurves, rational Béziers and clamped-cubic NURBS are first-class primitives. Intersections, offsets, distances, curvature, G0–G3 continuity blends and planar booleans are computed numerically, with Shewchuk-exact orientation predicates and magnitude-relative tolerances keeping results robust even on near-degenerate or large-coordinate input. The viewport renders through the egui painter with adaptive, zoom-aware tessellation and viewport culling — smooth curves at any zoom, only what's on screen is drawn.

⬇ Download

Pre-built binaries for Windows, Linux and macOS (Intel + Apple Silicon) are published on every release:

→ Download the latest release

Or build it yourself in one command (see Build & run).

✨ Features

Draw

• Line and Polyline
• Circle — center+radius, 2-point (diameter), 3-point, tangent-tangent-radius (TTR), tangent-tangent-tangent (TTT)
• Arc — 3-point, start-center-end, center-start-end
• Tangent line — from a point or common to two circles/arcs
• Ellipse (center + two axes), Rectangle, Polygon (n-sided, type the count)
• NURBS spline — control-vertex authoring with draggable CV grips and per-vertex weights
• Text with a user-selectable on-canvas font (TTF/OTF), drawn as filled vector outlines; multi-line supported

Modify

• Move, Copy, Rotate, Scale, Mirror, Stretch
• Cut / Copy / Paste (Ctrl+X / C / V) — paste lands at the cursor
• Offset — segment-mitred for polylines/polygons, exact for NURBS
• Trim & Extend — span-aware and spline-preserving
• Fillet & Chamfer — on two lines or around polyline corners
• Blend — bridge two entities (line, arc or spline) with a spline at G0 / G1 / G2 / G3 continuity (positional, tangent, curvature, or curvature-rate); pick the continuity and tension live in the cursor HUD
• Disjoint (explode) and Join
• Hatch — region-based fill (solid, line, cross-hatch or dot patterns) with island detection
• CAD-style grips on every selected entity — drag to reshape, or type an exact value
• Contextual corner fillet/chamfer dots and bounding-box transform handles
• A floating contextual toolbar (duplicate, mirror, rotate, offset, delete) above the selection — follows multi-selections too

Dimensions

• Linear / Aligned — distance between two points, parallel to the measured span
• Horizontal / Vertical — axis-locked linear dimensions
• Angular — from three points (vertex + a point on each side) or from two picked lines
• Radius / Diameter — pick a circle or arc, then aim the leader (R / ⌀)
• Per-dimension text override, and a drawing-wide decimal-precision setting
• One shared dimension style (text height, arrow size, font, precision); dimensions land on an auto-created Dimensions layer

Parametric constraints

• Geometric — Horizontal, Vertical, Parallel, Perpendicular, Collinear, Equal length, Equal radius, Concentric, and Tangent (line↔arc and arc↔arc)
• Point relations (pick-based) — Coincident/weld, Midpoint, Point-on-line, Point-on-circle, and Symmetric (mirror two points about a line); pick the points on canvas rather than pre-selecting
• Driving dimensions — lock or drive a circle/arc's radius (RADCON / DIACON), a line's length (LENCON), the angle or width between two lines, or a point-to-point distance (straight / horizontal / vertical); a bare command holds the current value, a numeric argument resizes to it
• Fix a piece in place, or Block a whole selection into a rigid group that only translates and rotates
• Live inference — while drawing, a glyph at the cursor previews the Horizontal / Vertical / Coincident relation that will be captured on the next click; toggle auto-constrain off to draw freely
• Validity-aware toolbar — each constraint button enables only when the current selection is a valid target, with a tooltip saying what it needs
• Degrees-of-freedom readout in the status bar — Fully constrained (green) or N DOF for the active constraint group; a rejected constraint briefly flashes the conflicting geometry red
• Constraints re-solve live as you drag grips, move, or edit properties — a minimal-motion numeric solver pulls constrained neighbours along and keeps welded corners together
• On-canvas glyph badges show what's constrained; click a badge to delete that constraint, and the Properties inspector lists (and removes) every relation on the selection

Snapping & input

• Object snaps — Endpoint, Midpoint, Center, Quadrant, Intersection, Perpendicular, Tangent, Nearest, Node, Insertion (each individually toggleable, with on-canvas markers + labels)
• Grid and grid snap, polar / angle guides, and extension tracking
• Dynamic input HUD — type a length/angle, radius, width×height or side count right at the cursor; sizes grow in the direction you aim (no negative numbers needed)
• Coordinate entry — x,y absolute, @dx,dy relative, d<a polar absolute, @d<a polar relative (degrees)
• A translucent tool-hint panel (bottom-right) listing the active tool's keys, with getting-started tips on a blank canvas
• Cursor readout for move/copy/rotate/scale, and a live scale bar

Workspace & UI

• Layers — colour, show/hide, freeze, lock, rename, set-current, per-layer line type & weight; seeded with a sensible default set
• Editable Properties inspector — geometry, live measurements, colour, line weight, line type and layer; hatch-pattern editor; dimension text override
• Line types (Continuous, Dashed, Dotted, Center, or custom dash patterns) and line weights shown at a fixed on-screen scale
• Drawing units — mm / cm / m / km / in / ft / unitless — that bound the zoom range and label measurements
• Curvature comb on selected curves for smoothness inspection
• Ctrl+F command palette plus an always-available command line, window / crossing marquee, hover highlight, ghost previews, undo / redo
• Radial tool wheel — press Q for a Tools / Modifiers picker at the cursor; move toward either to reveal its full ring, then to a wedge and click to activate it; press Q again or Esc to dismiss
• Modern dark, glass-panelled interface — top bar, inspector and status pill; preferences persist between sessions

Geometry kernel

• Curve primitives: line, circular arc, elliptical arc, cubic Bézier, rational Bézier, polycurve, clamped-cubic NURBS
• Numeric intersect / distance / curvature / offset / split / reverse; tangent solvers (3-point circle, TTR, TTT, tangent lines)
• Continuity blends — a single degree-2n+1 polynomial Bézier matching position, tangent, curvature vector and curvature rate at both joins for exact G0–G3
• Exact boolean region ops (union / intersection / difference / xor) via Greiner–Hormann clipping with robust winding
• Shewchuk-exact orientation predicates (via the robust crate); collinearity / parallelism tests use magnitude-relative tolerances so they hold at CAD-scale coordinates
• Affine transforms (translate, rotate, scale, mirror) — conformal-aware: a non-uniform scale or shear lowers a circle/arc to its exact rational form instead of corrupting it into a wrong-radius arc
• Fallible constructors (try_new + a GeomError enum) alongside the panicking new, so untrusted/imported geometry is rejected rather than crashing
• Shared numeric utilities (angle normalisation, point/segment distance) reused across every crate — 100% safe Rust (unsafe is forbidden workspace-wide)

Interoperability

• Native .o2d format — lossless, atomic saves (opens old .e2d files too)
• DXF (ASCII) — import & export
• SVG — import & export
• Dimensions export to DXF/SVG as ordinary lines + text (so they render anywhere)

⌨ Commands

Type a verb in the command line, or use the Draw/Modify menus, the radial tool wheel (Q), or the Ctrl+F palette. Common aliases:

Draw		Modify		Other
LINE / L	Line	MOVE / M	Move	SELECT / SE	Select
POLYLINE / PL	Polyline	COPY / CO	Copy	ERASE / E / DELETE	Delete
CIRCLE / C	Circle (center, radius)	ROTATE / RO	Rotate	DISJOINT / X	Disjoint (explode)
CIRCLE2P / C2P	Circle (2 points)	SCALE / SC	Scale	JOIN / J	Join
CIRCLE3P / C3P	Circle (3 points)	MIRROR / MI	Mirror	HATCH / H	Hatch
TTR · TTT	Tangent circles	OFFSET / O	Offset	UNDO / U	Undo
ARC / A	Arc (3-point)	TRIM / TR	Trim	REDO	Redo
ARCSCE · ARCCSE	Arc (SCE / CSE)	EXTEND / EX	Extend	ALL	Select all
TANGENT / TAN	Tangent line	FILLET / F	Fillet	ZOOM / Z	Zoom / extents
ELLIPSE / EL	Ellipse	CHAMFER / CHA	Chamfer	LAYER / LA	Layer set / new
RECTANGLE / REC	Rectangle	BLEND / BL	Blend (G0–G3)
POLYGON / POL	Polygon	STRETCH / S	Stretch
SPLINE / SPL	NURBS spline	DIMENSION / DIM	Dimension (linear/angular/radius read off the pick)
TEXT / T / MTEXT	Text

POLYGON n and TTR r accept an inline argument (side count / radius), and BLEND g2 1.5 presets the continuity and tension. Polyline and spline finish with Enter or right-click, and close with C.

Constrain the current selection with HOR · VER (horizontal / vertical), PAR · PERP (parallel / perpendicular), COLL (collinear), EQL (equal length), EQR (equal radius), CONC (concentric), TANCON (tangent), RADCON · DIACON (drive a radius / diameter) and LENCON (drive a line's length). The value commands take an optional number — RADCON 2.5, LENCON 40 — or lock the current value when bare. The point relations COI (coincident/weld), MID (midpoint), PTL (point on line), POC (point on circle) and SYM (symmetric) pick their points on canvas. BLOCK locks the selection into a rigid group; FIX pins it in place; UNCON drops every constraint on the selection.

Keyboard shortcuts

Key	Action	Key	Action
L P C E A R G S T H	Line / Polyline / Circle / Ellipse / Arc / Rectangle / polyGon / Spline / Text / Hatch	Ctrl+N O S	New / Open / Save
Shift+ M C R S A I	Move / Copy / Rotate / Stretch / scAle / mIrror	Ctrl+Shift+S	Save As
Shift+ O T E F H B	Offset / Trim / Extend / Fillet / cHamfer / Blend	Ctrl+Z · Ctrl+Y	Undo / Redo
Shift+ X J	disjoint (eXplode) / Join	Ctrl+X C V	Cut / Copy / Paste
Esc	Cancel / deselect	Ctrl+A	Select all
Z	Zoom extents	Ctrl+F	Command palette
Space	Repeat last command	Del	Delete selection
Q	Radial tool wheel — move to Tools or Modifiers, then a wedge
F7–F12	Toggle object snap · grid · grid snap · polar · tracking · dynamic input

🔨 Build & run

Plain Cargo, no special toolchain — just a stable Rust toolchain.

cargo build --workspace
cargo test  --workspace

cargo run -p oxidraft_app          # launch the interactive CAD window
cargo run -p oxidraft_app -- demo  # headless geometry-kernel demo

Linux build dependencies: the file dialogs use GTK, so install libgtk-3-dev (Debian/Ubuntu: sudo apt-get install libgtk-3-dev) before building.

🧱 Architecture

oxiDraft is a Cargo workspace — the kernel is fully decoupled from the UI, so every crate below oxidraft_ui is headless and independently testable. Shared package metadata, dependency versions and lints are defined once at the workspace root and inherited by every crate.

Crate	Responsibility
oxidraft_geometry	Curve primitives (line, arc, ellipse, cubic, rational, polycurve, NURBS), conformal-aware transforms, ops (intersect / distance / curvature / offset / split / tangent / blend), and shared numeric utilities (angle / point-segment helpers) reused across every crate
oxidraft_spatial	Adaptive quadtree + Morton-code spatial index (standalone; reserved for upcoming query acceleration / 3D — picking currently uses bounding-box-filtered scans)
oxidraft_boolean	Planar region boolean ops (union / intersection / difference / xor) with robust winding
oxidraft_document	Document / layer / entity / block model, plus the shared dimension geometry + labelling used by both the renderer and the exporters
oxidraft_cad	Snapping, selection, grips, draw + edit (trim / extend / fillet / chamfer / blend / offset / hatch / join / explode / inquiry)
oxidraft_io	DXF, SVG and native .o2d import / export
oxidraft_ui	Headless app state + egui view (toolbars, canvas, panels, command palette, dialogs)
apps/oxidraft_app	eframe GUI host + headless kernel demo

.o2d is the current native format (was .e2d before the project's rename from eiderFLAT to oxiDraft) — the loader still reads old .e2d files, it just no longer writes them.

📄 License

oxiDraft is free software, licensed under the GNU General Public License v3.0 or later (GPL-3.0-or-later) — see LICENSE. You may use, study, modify and redistribute it under those terms; derivative works must remain GPL-licensed and share their source.