eSchema is a free, open-source 2D CAD editor for electrical/electronic schematics and PCB sketches, built with C++ and Qt 6. It uses FidoCadJ as its native drawing format, combining a lightweight, human-readable file format with a modern, dockable desktop UI.
Licensed under the GNU GPLv3.
A complete FidoCadJ primitive set, each with on-canvas resize handles, snap-to-grid placement, and mirror/rotate support:
- Line, Bézier curve, closed polygon, complex (spline) curve — with node add/remove editing directly on the canvas
- Rectangle and ellipse (filled or outlined)
- Arc (three clicks, live preview) and regular polygon (3–64 sides) tools, both emitting standard FidoCadJ primitives
- Linear dimension tool: two clicks to measure, a third to place the dimension line — arrows, extension lines, and the measured distance in millimeters, all built from standard primitives
- Connection dot and PCB track
- PCB pad
- Text labels, with superscript/subscript markup
- Raster images
- Macros (parts pulled from a component library)
- Bundled standard FidoCadJ libraries (electrotechnics, PCB footprints, and more)
- A dockable library browser with searchable, previewed parts and a large preview panel for the selected macro
- Build your own reusable macros directly from a selection on the sheet, and manage personal libraries/categories from the same panel
- Up to 16 independent, colorable layers, matching the FidoCadJ layer model
- A dedicated layer manager to rename, recolor, and toggle per-layer visibility and lock
- Configurable grid (dots or lines) with adjustable step and marked-line intervals
- Snap-to-grid for every placement, move, and resize operation, with one-click toggles for both right on the toolbar
- Object snap: clicks and drags capture endpoints, midpoints, centers, and intersections of what's already drawn, with a visual marker — each target kind individually configurable
- A measure tool (distance and angle between two clicks, live in the status bar)
- Photoshop/Illustrator-style rulers along the top and left edges of the canvas, synced live with the grid step and current zoom/pan — drag guide lines out of them: positions snap to the guides (and object snap captures their crossings), and they never reach print or export output
- Mouse-wheel zoom anchored to the point under the cursor, at any zoom level and anywhere on the sheet
- Align and distribute tools for tidying up a selection (left/right/top/bottom, center, even spacing), plus snapping a whole selection back onto the grid
- Zoom to fit the whole drawing or just the current selection
- A background tracing image drawn under the grid (Tools > Tracing image...), for redrawing schematics from photos or scans — persisted in the file, invisible to a plain FidoCadJ
- Full undo/redo history for every operation (create, move, resize, mirror, rotate, delete, node edits)
- Boolean operations between closed shapes — union, subtraction, intersection — with results that stay fully FidoCadJ-compatible (optionally as smooth complex curves)
- Shape tools: convert rectangles/ellipses/curves to editable polygons (and back to smooth curves), simplify nodes, fillet or chamfer corners, and grow/shrink a shape by a parallel outline offset (sharp corners preserved, original optionally kept, rectangles and ellipses stay exact)
- AutoCAD-style precision edits with live previews: split a line/curve/track at a clicked point, trim away the stretch of a line between its intersections, extend an end until it meets the first shape on its way
- Whole-selection transforms: rotate by an arbitrary angle, scale by percentage, and replicate on a grid or circularly (clock-face style, with a mouse-picked center)
- A dedicated Modify toolbar grouping every shape-editing command: rotate, mirror, booleans, transforms, align/distribute, macro explode
- Cut / copy / paste / duplicate, multi-selection, select all, invert selection, select same type — including pasting an image straight from the clipboard, paste in place (Ctrl+Shift+V), mirror as copy, and Alt+drag to drag off a duplicate
- Editable geometry right in the Properties panel: a line's length, a rectangle's or ellipse's width and height
- Find (Ctrl+F) across text, macro names, and name/value labels
- Nudge the selection by one grid step with Alt+arrow keys
- A dockable live FCD code panel: watch the drawing as FidoCadJ text while you edit, or edit the text and apply it back as one undo step
- Live status bar: cursor position (grid units and/or millimeters), zoom level, and running counts of primitives and macros in the drawing
- One export dialog for PNG, JPG, SVG, PDF, EPS and DXF, sized either by resolution (pixels per unit) or by an exact pixel size, with optional antialiasing, black & white, and one-file-per-layer splitting
- Copy the current selection (or the whole drawing) straight to the clipboard as an image
- "Copy split" and "Save split as..." to copy/save with every macro expanded into raw primitives, leaving the drawing itself untouched
- Print with mirroring, black & white, landscape orientation, custom margins, and an option to print a single layer only — fit to page or at true real scale (one unit = 0.127 mm, adjustable percentage) for dimensionally exact output, e.g. toner-transfer PCB etching
- Opens and saves the standard
.fcddrawing format and.fcllibrary format - Faithful, idempotent round-tripping — including the
FCJextensions (dash styles, arrowheads) and per-documentFJCconfiguration - Also available as a headless command-line converter (
eSchema -n -c ...) for scripted batch conversion to any of the supported export formats
The complete specification of the FCD drawing format and the FCL library
format — lexical rules, every primitive, the FCJ/FJC extensions, macro
libraries, and worked examples — is bundled in
FIDOSPECS.md. It is the reference eSchema's reader and
writer are documented against (the source comments cite its section numbers
throughout). Originally written by Dante Loi for the
FidoCadJS project; this copy adds a
preface with the deviations and errata verified against the reference
FidoCadJ implementation.
- Import and export AutoCAD DXF drawings, powered by the libdxfrw library
- A best-effort mapping between FidoCadJ primitives and DXF entities (lines, circles/ellipses, arcs, polylines, splines, text, blocks) in both directions, with a post-import summary of anything that couldn't be mapped
- Autosave with a configurable interval, and crash recovery on the next startup if eSchema didn't close cleanly
- Optional
.bakbackup copy of the previous version on every save - Recent Files menu (configurable length), drag-and-drop of
.fcd/.dxffiles straight onto the main window, and an option to reopen the last file on startup - Files with content outside the drawing area (e.g. negative coordinates) are shifted back onto the sheet on open, so nothing loads stranded out of sight
- Update checker: automatic on startup (can be turned off) or on demand from the Help menu
- Dockable, floatable, tabbable panels (Libraries, Properties, FCD code) — arrange your workspace however you like; the layout, window size, and position are all remembered between sessions
- Customizable toolbars: add, remove, and reorder the commands on the main and Modify toolbars, like in professional CAD packages
- Customizable keyboard shortcuts: reassign or remove any command's shortcut from a searchable editor, with conflict handling and one-click restore of the defaults
- A command palette (Ctrl+Shift+P): search and run any command by name, VS Code-style
- A searchable Options dialog organized in pages, with a live grid preview and per-page defaults — from toolbar icon size and mouse-wheel behavior to snap targets and marker colors
- Seven built-in themes — Light, Dark, Nord, Midnight, Graphite, Sepia, Ocean — each with its own gradients and UI font, plus custom stylesheet support
- A fully translated, multi-language interface (see below)
eSchema's interface is available in:
| 🇬🇧 English | 🇮🇹 Italiano | 🇩🇪 Deutsch | 🇫🇷 Français |
| 🇪🇸 Español | 🇷🇺 Русский | 🇨🇳 中文 | 🇵🇱 Polski |
| 🇯🇵 日本語 | 🇵🇹 Português | 🇸🇦 العربية | 🇮🇳 हिन्दी |
English is the language the interface is natively written in, and Italian is maintained natively by the project too (this is originally an Italian-authored app). The other 10 translations are complete but were produced with the help of Claude (Anthropic's AI assistant) and have not been reviewed by native speakers — some strings may be awkward or plain wrong. If you spot an incorrect translation, please open an issue or a pull request against the corresponding translations/eSchema_<lang>.ts file; corrections from native speakers are very welcome.
| Layer manager | Circular array of copies |
|---|---|
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- Qt 6.x (Widgets, Gui, Core, PrintSupport, Svg)
- A C++17-capable compiler (MSVC, MinGW, or GCC/Clang on Linux/macOS)
qmake eSchema.pro
# MinGW / Linux / macOS
make # or: mingw32-make
# MSVC
nmakeThe resulting binary picks up the bundled component libraries from the lib/ folder next to it at runtime.
Just open eSchema.pro in Qt Creator, pick a Qt 6 kit, and build/run — no extra configuration needed.
- SVG import: the full path grammar (arcs included), nested groups with transforms and inherited colors, viewBox mapping, physical-size scaling — straight shapes become polygons/lines, lone cubics become Béziers, curved outlines become smooth complex curves, and distinct colors claim layer slots like DXF layers do
- One Open dialog for every format: File > Open lists
.fcd,.dxfand.svgtogether and routes by extension — the separate "Import from DXF" menu entry is gone, and drag & drop accepts SVG too - DXF imports are finally in scale: the declared
$INSUNITSunit (mm, inches, cm, ...) rescales the geometry onto the drawing unit, so the dimension tools report the original's real millimeters; imported layer colors are contrast-guarded against the canvas (no more invisible white-on-white drawings), and imports land centered on the sheet instead of hugging its corner - Hatch tool (Edit > Shape > Hatch): fills the selected closed shapes with clipped parallel lines — angle, spacing, optional cross-hatch — generated as plain lines, so files stay fully FidoCadJ-compatible (holes from boolean keyhole polygons are respected)
- Layers panel: the layer manager is now a dockable panel (Ctrl+L) that lives alongside the drawing instead of a separate window
- Welcome card on new empty drawings: recent files with preview thumbnails, quick tips, and a "show on new drawings" toggle; hovering an Open Recent entry shows a rendering of that drawing beside the menu
- Selection mirrored in the FCD code panel: selecting primitives on the canvas highlights their exact lines (FCJ/TY follow-ups included) and scrolls them into view
- More GUI polish: right-click menu on document tabs (close/close others/close all, copy path, open folder), clickable zoom readout in the status bar with presets and exact value, macros draggable from the Libraries panel straight onto the sheet, recently used commands first in the command palette, and a freshly created document now really comes to the front with focus
- View behavior: opening any file fits and centers it automatically, zoom-out reaches far enough to frame even sheet-filling drawings, and fit/wheel zoom stay consistent at every level; the drawing area grows to 20000 units per side
- Format-compatibility fix: name/value labels are attached only when announced by an
FCJmarker, exactly like the reference FidoCadJ parser — text primitives directly following an unlabeled macro are no longer swallowed as its labels (and eSchema now writes the marker itself); the bundled FIDOSPECS.md documents the corrected rule
- Multiple documents: any number of drawings open at once, as tabs in the drawing area — drag a tab to split them side by side, stack them back together, or float a drawing in its own window, all with Qt's native dock drag-and-drop and IDE-style slim tabs with a close button
- Per-document everything: each drawing keeps its own undo/redo history, file path, and layer configuration (names, colors, visibility, locks, master layer) — switching tabs swaps them seamlessly, and every existing command simply acts on the active drawing
- Window menu: the open documents listed with the active one checked, plus Ctrl+Tab / Ctrl+Shift+Tab to cycle through them
- Save all (Ctrl+Shift+S): saves every modified document in one go — named files silently in place, untitled ones through Save As each
- Autosave covers every open document: each modified drawing gets its own recovery sidecar, and after a crash the next launch offers to restore all of them, each into its own tab
- AutoCAD window/crossing selection: dragging left-to-right (solid blue) selects only what's fully inside the rectangle, right-to-left (dashed green) also what it merely touches; Ctrl/Shift extends the existing selection
- Opening an already-open file activates its tab instead of loading a duplicate; dropping several files on the window opens each in its own tab; new drawings are numbered "New drawing 1, 2, ..."
- The command palette now opens only via its shortcut or by typing in its search field — no more accidental popups when switching tabs
- Every class and method in the source headers is now documented
- Pixel-faithful FidoCadJ rendering: text em size, vertical stretching and label anchoring now follow the reference editor's exact formulas, label TY font families and sizes are honored (e.g. Bitstream Charter) and round-tripped, dash patterns and round caps match
Globals.dash, and arrow terminators combine the triangle with the limiter bar and shorten the stroke to the arrowhead's base - side-by-side drawings now look the same - Dynamic cursor tooltip while drawing (length/angle, width × height, radius - Options > Drawing) and object snap tracking: hovered snap points become alignment references with dashed alignment lines, AutoCAD-style (Options > Snap)
- Move/Copy with base point: pick a base point on the selection, then its destination, with full snapping on both picks and a live half-opacity preview
- Right-click ends the command: while drawing, a right click discards the preview, returns to the Select tool and opens the context menu in one gesture; right-clicking never deselects anymore
- Line style and arrow style combos now paint the real patterns/terminators on a fixed white background in every theme, and the line style shown always matches the selected primitive
- Theme polish: disabled menu entries are dimmed everywhere, every icon (layer eyes/locks, master bookmark, dock tabs, Layer manager) follows a live theme switch, and switching themes suggests a restart
- Properties panel: arrow rows grouped together, and a centered hint appears when nothing is selected
- Fixes: hiding the grid no longer changes the canvas background, pasting into an empty drawing fits the view to the result, and Fit-to-selection is disabled without a selection
- Fixed a black drawing canvas, black toolbar icons, and a crash on mouse movement, all on the very first launch of a fresh install (no settings file yet)
- Fixed theme rendering on Linux: toolbar areas no longer stay black in dark themes, and the light themes no longer inherit a dark desktop's system palette
- The default grid style is now dots, matching FidoCadJ's classic look
- Fixed the Linux/macOS portable packages: the app failed to start with "Qt libraries not found" because the zip step turned a symlink into a stray duplicate of the binary outside its library folder
- Parametric symbol wizard (Tools > Symbol wizard): DIP/SIP/quad packages in through-hole, SMD, or schematic style, pin numbers and/or names, live preview, saved straight into any user library — including a brand-new one created from the same dialog
- Angular and radial dimension tools with AutoCAD-style picking: hovering highlights the two lines (rectangle edges work too) or the circle, and the center is found automatically
- Title-block library: ready-made A4/A3 drawing frames at real paper sizes
- Hold Shift while drawing to constrain lines to 45° steps and rectangles/ellipses to squares/circles
- Offset rework: the dialog asks only the distance, then the mouse picks the side with a live preview until you click (AutoCAD-style); offset polygons and curves keep exactly the original node count, and every base primitive can now be offset (lines, Béziers, rectangles, ellipses, polygons, complex curves)
- The command palette search box now sits centered in the menu bar
- Nord is the default theme on a fresh install
- Reliability fixes from a full code review: an undo/redo double free, dangling layer pointers after deleting a layer, verified atomic saves/exports, DXF import/export hardened against malformed files, and lifetime fixes around tool previews
- Performance: settings reads are cached and selection/settings/clipboard notifications are coalesced, removing multi-second freezes with large selections or when applying options
- Customizable toolbars (View > Customize toolbars...): add, remove, and reorder the commands on the main and Modify toolbars
- Customizable keyboard shortcuts: the shortcut list becomes a searchable editor — reassign or remove any command's binding, with conflict handling and one-click defaults
- Command palette (Ctrl+Shift+P): search and run any command by name
- Guide lines dragged out of the rulers, Illustrator-style: positions snap to them, object snap captures their crossings, and they stay out of print/export output
- New Dimension tool (D): arrows, extension lines, and the measured distance in millimeters, placed with a live preview and built from plain primitives
- AutoCAD-style edits with live previews: split at point, trim to intersection, extend to intersection
- Paste in place (Ctrl+Shift+V) and Mirror as copy
- Offset outline improvements: optionally keep the original shape, corners stay sharp, rectangles and ellipses produce exact rectangles/ellipses
- Real-scale printing: fit to page or a true physical scale (one unit = 0.127 mm, adjustable percentage)
- Five new built-in themes — Nord, Midnight, Graphite, Sepia, Ocean — with gradients and per-theme fonts, plus many dark-theme legibility fixes (dialog buttons, menu bar, layer and library icons)
- Mouse-wheel zoom anchored to the cursor; files with off-sheet content are pulled back into view on open
- Icons on every menu entry, red control-point markers on all drawing-tool icons, and an Options dialog that applies changes instantly instead of freezing
- Object snap: clicks and drags capture endpoints, midpoints, centers, and intersections of what's already drawn, with a visual marker and per-kind configuration
- New drawing tools: Arc (U) and Regular polygon (N), plus a Measure tool (W)
- Shape tools: convert to polygon/complex curve, simplify nodes, fillet/chamfer corners, parallel outline offset
- Transforms: rotate by arbitrary angle, scale by percentage, array of copies (grid or circular, with a mouse-picked center)
- Selection conveniences: Alt+drag duplicate, invert selection, select same type, snap selection to grid
- Editable geometry in the Properties panel (line length, rectangle/ellipse size)
- Completely reworked Options dialog: searchable sidebar pages, live grid preview, per-page defaults, and many new options (backup
.bakon save, undo limit, reopen last file, toolbar icon size, antialiasing, coordinate units, wheel zoom, snap tuning, default fonts and colors...) - Libraries/Properties/FCD panels tabbed on the right by default, with tab icons; window size and position remembered
- Fixes: stale version shown in the About box / false update notifications, main window no longer blocked from shrinking, left-side docking
- Boolean operations between closed shapes (union, subtraction, intersection), applied as one undo step; curved results can optionally come out as smooth complex curves instead of flattened polygons
- New Modify toolbar, docked below the main one, grouping every shape-editing command (rotate, mirror, booleans, align/distribute, macro explode)
- Dockable live FCD code panel — see and edit the drawing as raw FidoCadJ text
- Background tracing image under the grid (Tools > Tracing image...), persisted in the
.fcdfile - Find (Ctrl+F) across text, macro names, and name/value labels
- Large macro preview panel in the Libraries dock
- Paste an image from the clipboard; "Copy split" / "Save split as..." with macros expanded
- Update checker, automatic on startup or manual from the Help menu
- All 11 non-English translations completed (100%)
- Fixed docking to the left side; the saved window layout is now versioned
- Unified export dialog (PNG/JPG/SVG/PDF/EPS/DXF) shared with the new headless command-line batch converter; EPS export added
- Autosave with crash recovery
- Print options: mirror, black & white, landscape, margins, single layer
- Recent Files menu, drag & drop of
.fcd/.dxf, unsaved-changes prompts - Node insertion/removal on polygons and complex curves
- Zoom to selection, Alt+arrows nudge, "Copy as image"
- Decorated text (superscripts/subscripts) and working per-layer visibility/lock
- FidoCadJ-style grid rendering and default 5-unit pitch; grid/snap toggles on the main toolbar
- English became the source language of the interface
- DXF import/export, powered by libdxfrw
- Light/dark/system themes with custom stylesheet support
- First stable release (BETA label dropped), with automated release packaging for Windows, Linux and macOS
- Multi-language interface (11 translations)
- Rulers along the canvas edges and live primitive/macro counts in the status bar
- Image primitive with opacity, grayscale and aspect-ratio lock
- PDF/SVG/PNG export from the File menu and a reorganized Options dialog
eSchema is under active development. The core drawing engine, the full FidoCadJ primitive set, layers, libraries, undo/redo, file I/O, export/printing, and autosave are all in place and usable day to day. Expect rough edges and missing niceties in less-traveled corners of the UI — bug reports and feature requests are welcome.
Issues and pull requests are welcome — for code changes, translation fixes, or anything in between. If you're planning a larger change, consider opening an issue first to discuss the approach.
eSchema is released under the GNU General Public License v3.0.
- FidoCadJ — the native file format and component libraries eSchema builds on
- libdxfrw — DXF import/export (vendored under
third_party/libdxfrw/, GPL-2.0-or-later) - Remixicon — toolbar and UI icons
- dafont.com — bundled fonts