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Requires macOS 15 Sequoia or later. Universal binary (Apple Silicon & Intel).
A deep dive into every feature of the most complete GRBL laser controller for Mac
From a built-in shape and text editor to image engraving with 7 dithering algorithms, SVG vector cutting, multi-item layers, 18 material presets, and real-time overrides — Lùmen gives you full control over your laser engraver.
Before you fire the laser, Lùmen shows you exactly what will happen. The interactive 2D canvas displays your entire job with zoom and pan, the machine's real work area in millimeters, and the current laser position.
The Frame command traces the exact boundary of your job before engraving — so you can verify placement without burning anything. With the laser pointer active, the machine moves at low power (S10) to draw a visible outline on your material. With the pointer off, it traces the boundary with rapid moves.
Framing respects work area limits in Machine Home mode, preventing end-stop alarms.
Lùmen isn't just a sender — it's also an editor. Draw rectangles, ellipses, lines, polylines, and multi-line text directly on the canvas, no Inkscape or Illustrator needed for simple jobs.
A floating toolbar in the corner of the canvas offers five tools:
After committing a shape, the tool auto-switches back to Select — you can immediately move it or tweak its parameters without an extra click.
Selected shapes show 9 handles: 4 corners, 4 edge midpoints, and a green rotation handle above the top edge. Resize is anchor-locked: the opposite corner stays visually fixed even when the shape is rotated. The math projects the cursor through the shape's unrotated frame and recomputes the bounds so the visual anchor never drifts — exactly like in pro design tools.
Hold Shift on a corner handle to lock the original aspect ratio during resize.
On the Engrave layer every item has two intensity sliders: Fill and Stroke, from 0 to 100%. Intensity is also a multiplier on the layer's laser power: a rectangle with 50% fill burns at half the configured power for the Engrave layer.
Each layer has its own identifying color on the canvas: blue for Engrave (matching the rasterized toolpath), red for Cut (matching the imported SVG). The blue alpha tracks intensity: solid blue = full burn, transparent blue = reduced power. You can tell what does what at a glance.
On the Cut layer, shapes are always stroke-only (filling an area to cut it makes no sense) and per-item intensity is hidden: the layer's power / feed / passes govern every cut. Shapes added to Cut are automatically coerced to stroke-only, and you can still select them by clicking inside the outline — not just on the edge.
The X, Y, W, H, and ∠ fields in the layer panel accept exact numeric values in millimeters and degrees. Shapes can be rotated by an exact value (e.g. 45°), moved to precise coordinates, resized to exact millimeters — no dragging required. Every change reflects instantly on the canvas.
The engrave image can now be rotated too: a green rotation handle appears when the engrave layer is selected. The rotation is baked into the G-code the laser will execute — not just a visual effect.
Photoshop / Figma style: each layer (Engrave / Cut) expands to show every item it contains. Click an item to select it, edit its parameters inline. The + button on each layer offers contextual actions: add an image / G-code / SVG (replaces if one is already there), or activate a drawing tool to place new shapes.
Multi-line text works exactly as you'd expect: there's a multi-line editor in the panel, press Enter for a new line, the text is laid out with the font's natural leading via CoreText.
Text items expose three pickers driven by every font installed on your Mac: Font (family), Width (Condensed / Compressed / Normal / Expanded …, shown only when the family has more than one), and Style (Regular / Bold / Italic / Bold Italic / …). Switch family and Lùmen preserves the current width + style if the new family supports them — e.g. going from Helvetica Condensed Bold Italic to Courier keeps Condensed Bold Italic when available, with graceful fallback otherwise.
Font size is a TextField + stepper combo: type an exact value in millimeters, or focus the stepper and use ↑ / ↓ to nudge by 1 mm.
Lùmen's v2 .gcode format includes a JSON block with every shape, geometry, style, and editable text. Reopen a project and find everything still editable — no flattening to curves or pixels. The file stays compatible with other senders that read only the plain G-code (it's saved as well, as a compatibility cache).
Lùmen converts your images to laser-ready G-code with three distinct processing modes, each suited to different materials and styles.
Converts your image to black-and-white dots using error-diffusion algorithms. This is the gold standard for engraving photographs on wood, producing fine detail with excellent contrast. Choose from 7 algorithms:
Maps continuous tones directly to laser power levels, producing smooth gradients. Best on materials that respond linearly to power changes, like anodized aluminum or slate.
Binary conversion: every pixel becomes either fully burned or untouched. Adjustable threshold (0–255) lets you control the cutoff point. Ideal for high-contrast logos, text, and line art.
Both adjustable from −100 to +100 with instant preview. The interface shows your original image side by side with the processed result, so you can evaluate the output before generating G-code.
PNG, JPEG, BMP, and TIFF.
Load any SVG file for precise vector cutting. Lùmen's built-in SVG parser handles all standard elements and converts them to optimized G-code.
Curves are automatically converted to linear segments for G-code. The cut layer appears in red on the canvas, clearly separated from the blue engrave layer.
Combine engraving and cutting in a single job. Lùmen's two-layer system lets you engrave a design and cut its outline without repositioning your material — and each layer can hold any number of items: shapes, text, the imported image, the SVG.
No guesswork. Every parameter is adjustable via dedicated sliders, and the preview updates in real time as you make changes.
| Parameter | Range |
|---|---|
| Resolution | 1–20 lines/mm |
| Speed (Feed Rate) | 100 mm/min up to machine maximum |
| Power Max | 1–100% (auto-scaled to machine $30 value) |
| Power Min | 0–100% |
| Overscan | 0–20 mm |
| Brightness | −100 to +100 |
| Contrast | −100 to +100 |
| Threshold | 0–255 |
During a running job, you can adjust feed rate and laser power without pausing. Controls allow ±1% and ±10% adjustments, or a reset to 100%. Changes apply instantly through GRBL's real-time command protocol.
Ready-to-use presets for the most common laser engraving and cutting materials. Select a preset and all parameters — speed, power max, power min, resolution, and passes — are set automatically.
Found the perfect settings for a material? Save them as a custom preset. Create, edit, rename, and delete your own presets — they persist across sessions and are always one click away in the dropdown menu.
The fastest way to find optimal settings for a new material. Lùmen generates a calibration grid where each cell is engraved at a different combination of speed and power, so you can visually identify the best parameters.
Run the test, pick the cell that looks best, and apply those parameters to your job.
Two modes for positioning your work, depending on your setup and workflow.
Uses the machine's limit switches to establish a repeatable zero position. Work area limits are enforced automatically — Lùmen prevents movements and G-code coordinates from exceeding the physical boundaries, avoiding hard-limit alarms.
Jog the laser to any position and press Set Zero Here. Your job will be engraved relative to that point. Supports two alignment modes:
8-direction jog pad with configurable step size in millimeters. The laser pointer toggles a low-power visible dot (S10) so you can see exactly where the focus point is without burning your material.
Lùmen implements the GRBL character-counting streaming protocol with precise 127-byte buffer tracking. Every command is tracked from send to acknowledgment, preventing buffer overflows and ensuring reliable communication.
If the machine stops responding during a job, Lùmen detects the stall after 3 consecutive idle status reports and automatically resynchronizes the buffer state. No manual intervention needed.
Stopped mid-job? Resume from the exact G-code line where you left off with the Resume button. No need to start the entire job over.
The built-in console shows all serial communication in real time:
Type G-code commands manually, navigate command history with arrow keys, and export the full log as a text file for debugging or support.
Save your entire job — both layers, every shape and text item, all settings, positions, sizes, and rotations — into a single .gcode file in Lùmen's v2 native format.
Built-in presets for the most popular GRBL laser engravers. Each preset configures the work area dimensions and maximum speed/power values for your specific machine.
Don't see your machine? Create a custom preset with your work area size and max values. Custom presets are saved permanently and editable at any time.
Lasers are powerful tools. Lùmen includes multiple safety layers to prevent accidents and protect your machine.
No credit card required. One-time purchase. No subscription.
Requires macOS 15 Sequoia or later. Universal binary (Apple Silicon & Intel).