Help
Basics
Everything in plotblock is measured in millimetres. The page is a real sheet: what you see on the canvas is exactly what ends up in the SVG and what the plotter draws.
Keyboard shortcuts
| V | Select |
| B | Draw |
| T | Text |
| E | Eraser |
| F | Fill |
| C | Cut line |
| Hold space | Pan the view |
| Cmd/Ctrl + wheel | Zoom to the pointer |
| Cmd/Ctrl + Z | Undo (with Shift: redo) |
| Cmd/Ctrl + E | Export SVG |
| Del | Delete the selection |
Setting up the page
In the properties panel on the right you pick the format or type free dimensions in millimetres. The list holds the paper sizes A6 to A3 and the usable work area of the common machines — AxiDraw, Brother ScanNCut, Cricut, Silhouette and xTool, grouped by maker. Start typing to search it: a maker (“cricut”), a model (“cameo pro”) or a measurement (“305”) all find an entry. The toggle below switches between portrait and landscape, and changing the format keeps the current orientation.
Calibrating the screen
At 100 % zoom one centimetre on screen should be a real centimetre. Monitors differ in pixel density, so that is not true by itself — “Calibrate screen…” lets you match it once against a ruler. It has no effect on the export, which is always true to size.
Drawing
The pen (B) draws freehand strokes. Set the stroke width in the properties panel on the right — it is the width of your pen in millimetres, not how it looks on screen. 0.3 mm is about a fineliner.
- Erasing: hold and drag across anything to delete it. The whole drag is a single undo step.
- Fill (F): turns a closed stroke into a filled area.
- Cut line (C): exports the path as a thin line instead of an outline — for cutting plotters.
- Moving and rotating: click with the select tool, drag the frame, rotate at the handle above the selection.
Type
Press T, click on the canvas and type. Shift+Enter breaks the line, Enter finishes. Then set font, size, letter spacing, line height and alignment on the right.
Type appears as an outline, not filled. That is not a display glitch but exactly the path the pen follows: Google Fonts are outline fonts, and the plotter traces their contours. The export contains paths only and no text element — so the file looks the same everywhere, even without the font installed.
In connected script faces the letters overlap. For a clean cut line, tick “Merge overlaps” on the right — the letters then become a single outline without doubled strokes.
Photograph a drawing and import it
The image button in the toolbar loads a photo or a scan. plotblock turns it into strokes — what lands on the sheet are ordinary strokes, just like the ones you draw yourself. A bitmap never enters the document and never the export.
The photo decides
More than half of the result comes down to the photo. Four points that almost always help:
- Even light, no flash. Daylight from the side, no hard shadows, no reflections on the paper.
- Shoot from straight above and fill the frame with the sheet.
- Use a dark pen. Fineliner, marker or a soft pencil. Light grey pencil on white paper has too little contrast.
- Keep the background out. Dark wood grain is as dark as the pen and gets traced along with it. If the table is in frame, “Detect sheet corners and straighten” crops to the sheet.
The dialog checks contrast, brightness and sharpness and tells you up front if any of them is off.
Centreline or outline
The most important choice. Tick “Compare both side by side” if you are unsure.
Centreline
Puts a line down the middle of each stroke. For thin, even strokes — handwriting, fineliner drawings. The plotter draws each stroke once, the way you drew it.
Outline
Traces the outer edge. For thick strokes and coloured-in areas, and whenever you cut rather than draw. Holes are kept.
The sliders
| Threshold | How much darker than its surroundings a pixel has to be to count as ink. Higher = only clearly dark things; lower = faint strokes too, but more noise. |
| Window size | How large those surroundings are. Larger helps with uneven lighting. |
| Denoise | Smooths paper grain while keeping edges sharp. 0 turns it off. |
| Remove specks | Drops dots below this size — otherwise the plotter puts down every speck of dust individually. |
| Fill coloured-in areas | An area coloured in with a marker otherwise comes out hollow — only its edge is detected. With this ticked it becomes solid. Deliberately hollow shapes such as frames, circles or an “O” stay empty. |
| Smooth edges | Takes the staircase of the pixel grid out. “light” removes the grid and keeps the shape; “medium” and “strong” smooth further and may lose fine detail. |
| Brush | Width of the masking brush, see below. |
| Width on the page | How wide the import lands on the sheet, in millimetres. You can change it afterwards. |
Masking out clutter
Drag across the preview to mask areas that should not be vectorised — the edge of the table, a shadow, your thumb at the edge of the sheet. Hold Shift to unmask. Masked spots are excluded rather than painted over in white, so no line appears at the brush edge.
Shot at an angle
“Detect sheet corners and straighten” looks for the sheet and removes the perspective. Detection is a heuristic and can get it wrong — the corners can be dragged by hand, and you can carry on without straightening at all.
After inserting
The import is selected right away and counts as one element: dragging moves all of it, the corner handles scale it evenly — without distorting —, the handle above rotates it, and Del deletes the whole import. The entire import is a single undo step.
If you do need a single stroke out of it — to delete one that was misread, say — hold Alt while clicking. The eraser always works stroke by stroke anyway.
Scaling leaves the stroke width as it is: it is the width of your pen, not part of the drawing.
Export
“Export SVG” or Cmd/Ctrl + E downloads the file. It is built so that plotter software handles it without clean-up:
- true to size in millimetres — the dimensions hold up in Inkscape,
- no transforms, all coordinates absolute,
- separate groups for strokes and type, so you can assign different pens,
- no text elements and no embedded images, paths only,
- grid, sheet outline and selection frame are not included.
The zoom of your view never ends up in the file — you can be zoomed in as far as you like when you export.
Saving
Your work is saved in the browser automatically and is back after a reload. The SVG is the result; the project file (.json) is the working file: it holds the whole document and can be loaded again — to carry on or to pass it along.
Two things worth knowing: undo does not survive a reload, and “Clear all” is written to the browser store half a second later. Save anything you care about as a project file.