Kurve · Bézier studio with curvature combs

Skip to controls

↖ Mette Virala

Kurve

Empty artboard. Pen is ready. Click to place a point, or drop an SVG.

Measure

Distance
Δx
Δy
Angle

this = Unit

Scale selection to

The ends snap to nodes and segment points of any path, then to the x or y of other nodes and to unit lines. Shift keeps 0, 45 or 90°. Unit from this sets the unit so this distance is the typed multiple (4/3 works); a new unit starts at A. Scale works about A, Move by B − A, both on the selected paths. Esc clears.

Fix & optimize

Select a path. Pen (P), κ-curve (K), pencil (N).

Clean up

Smooth

Shape

Corners

Structure

Hobby tension 1

Auto-curve, the κ-curve tool, pencil and pen clicks draw with this. Hobby is Metafont's spline: 1 is the default curve, higher tension is tighter. Pen-dragged handles stay.

Simplify tolerance 1 ‰

Drag to preview a fit with fewer nodes.

Simplify fits fewer nodes. Tolerance is per mille of the selection's size. Nodes land on extrema and the new joins are harmonized toward G2.

Doctor

Reading the mark…

A guess at the illustration kind, then the matching checks, so read the line. A row selects the spot; its button fixes it. Fix all T works on the selected paths, else every visible one, and fixes everything with one right answer: duplicate points, tiny, straight, crossed and escaped handles, balance, off-axis and missing extrema, G2 gaps, bowls off their circle and node types. Inflections, module snaps and jagged strokes are left for you.

Node

G2

X Y

Distance

X / Y place the primary node; the rest of the selection moves with it. Distance slides the selected nodes along their rails, the segments to unselected neighbours, and edits the last slide or edge push. Keep parallel holds a moving edge's angle; Even moves every node the same length. Auto keeps one edge parallel.

Align lines up two or more selected nodes of the path on the bounds of their anchors, or on the primary node (the one X / Y shows). Handles ride along.

Handle length Handle angle °

Click a handle to edit its length and angle. Fields commit on Enter or blur.

Out Fit Curve 55 % In Fit Curve 55 % Corner radius 0

Radius

No corners selected.

Corner smoothing 0 %

Trap depth Trap width

Radius takes a length (14.8, 0.1w) and rounds the selected corners live, or every corner of the selected paths; the nodes stay sharp underneath. The radius is kept as typed and fitted where a side is too short: two corners on a short edge share one circle (fit). Round all corners puts it on every corner, of the selection or the whole drawing. Smoothing eases the arc in and out with no curvature jump (G2), like a squircle. Ink trap cuts a notch.

How the opposite handle follows a smooth node's drag. X cycles.

Fit Curve

55% is circular. Click without dragging the pen commits a 55 ghost. Drag a handle toward its sage ghost to lock the mirror.

Diagnostics

Curvature comb C Handle tension % Corner circles Comb scale 1400

Comb density 48 Comb cutoff 4 ×

Off until you want it. C for the comb. Drag a tooth to set local |κ|. Auto normalises per path, log tames spikes, fixed keeps the scale between marks. Cutoff caps a tooth at that multiple of the median. Corner circles draws the circle of every rounded corner; the selected ones always show theirs. Dotted ones are path fillets next to a curve, not exact circles.

Kernel JS fallback

Construction

Construction grid A Circular trajectories Keep circular Sensitivity 60 %

Off until A. Circles sit on the fill, so leave them off for organic marks.

Polar rays from the inferred centre. Keep circular holds bowls on their circles while you drag; Circularize is under Fix & optimize.

Paths

Contours, not layers. Grab the mark (inside the box, off the curve) to move; a selected one carries the whole selection. Arrows nudge 1 px (a module with the grid on, a minor step with a snapping unit), Shift+arrows one module (1 px with either). ⌘D duplicates.

Hide and lock from the list. Shift-click rows to select several.

X Y

W H

Scale % Rotate °

X / Y place the selection's reference point and W / H size its ink (the true curve bounds; a group counts whole) about that point. Scale, Rotate and Flip turn about it too, or about the centre of selected nodes. A uniform scale scales corner radii.

Gap → Gap ↓

Align moves whole groups onto the selection's edge or centre, or onto the key object's: the primary (last selected) path, which stays put. Gap spaces the ink evenly from the first one; with two it sets their gap. A focused Gap field measures the gaps on the canvas.

Booleans need two or more selected paths; Subtract takes the rest away from the first selected. A group is one compound shape, so counters read as holes.

Offset

Stroke width

Offset keeps the original and adds the parallel outline outward; a negative distance goes inward. Expand turns the stroke into a filled shape.

Parts

Cut a shape into parts that merge back into the same outline: Knife ⇧K, Rectangle cut ⇧R and Shape Builder ⇧M on the toolbar. Parts of one shape export as one path per colour.

Helper lines L

Module

Helper lines show the module grid, a rail through every straight edge, part seams, sizes and links. While they are on, the part tools snap to the module.

Propose finds the fewest rectangles, so each part is a stroke. Rounded corners are squared for the count and stay curves. Works on the selection, else on every shape.

Split to module cuts the selection into cells. Merge unites the selected parts; with one part selected it rebuilds the whole shape. Stairs turns straight diagonal edges into steps at the module.

Body fills with the text colour, Accent with the signal colour. Linked copies share one outline: edit one and the others follow; moving one only moves it.

A TypeScript Mark with body and accent paths, ready for the ENTER wordmarks. Load an SVG from a link with ?svg= and markup, a data URL or an address.

Type

Text Font

Google Fonts

Font file

Style

Drop a font file, or browse TTF, OTF, TTC or WOFF. Parsed here; nothing is uploaded. Cap height 320

Em

Tracking 0 Kerning

Curated and Google fonts download from the google/fonts repository on first use. Em is the font size in document units, a number or an expression; 1:1 sets it to the font's units per em, so one unit is one font unit. Every contour becomes a path; a glyph's contours stay grouped, so counters read as holes.

Overshoot

Outside Add y

Band Factor %

Select letters and tick the lines their round shapes overshoot: flat stem tops and bottoms, at their exact y. Type a y or pick a point (a node, curve or grid point) to add a line on the Outside side. Nodes outside a line by up to the band move to the factor of their overshoot; handles move with them.

Grid & units

Show grid G Snap S

Grid starts off; snap stays on. A shown unit grid replaces the grid. Snap prefers the mirrored handle, so 55% stays 55%.

Size Origin X Origin Y

Any size works: 4 for a stroke-width module, 2 for half of it. With the grid on, arrows nudge one module and Shift+arrows 1 px.

A unit is a named length with its own grid: major lines every unit, minor lines every size / div. Length fields take 1.25w, 200/1.5 or 0.1u (the active unit). While the active unit snaps (the default), drags snap to its minor lines and arrows step one.

File

Document name Fill

Imported SVGs keep their fill. Black ink follows the theme. Uncheck for stroke only.

Drop an SVG, browse, or paste Drop appends when the board isn’t empty. Shift-drop replaces. Paste from Illustrator (⌘V). Nothing is uploaded.

Fill only, no strokes Trim to art

The name becomes the file name. SVG keeps the artboard, or trims its viewBox to the art; hidden paths stay out. PNG crops to the curves with 24 px of air. Corner radii are baked into both.

Reference

Drop a reference image, or browse PNG, JPG, WebP or SVG, under the grid. Files under 1.5 MB survive a reload.

Opacity 0.35 Locked (keeps opacity, fit and remove from changing it)

Versions

A snapshot lands here on its own about once a minute while you work, plus every save. Twelve are kept. ⌘⇧S saves.

Shortcuts

Tools

V: Select
P: Pen
K: κ-curve
N: Pencil
R: Rectangle
W: Warp pins
H: Pan
I: Measure
⇧K: Knife
⇧R: Rectangle cut
⇧M: Shape Builder
Space: Pan while held

Parts

Drag: Knife: a straight cut
Click: Knife: add a point, then 2× click or ↵ to cut
⇧Click: Knife: 45° steps
Drag: Rectangle cut: split the covered part off
⌥Drag: Rectangle cut: as an accent part
⇧Drag: Rectangle cut: cut it out
ClickDrag: Shape Builder: merge the faces
⌥Drag: Shape Builder: remove the faces
Esc: Cancel the cut
L: Helper lines

Warp

Click: Pin inside a shape (drag right away to pull it)
Drag: Pull a pin; the other pins hold
⇧Drag: Pull in 45° steps
⌥Click: Remove the pin
⌫: Remove the pin touched last, ⇧ every pin on the shape
[]: Reach of the pull (the dashed ring)
Scroll: Reach while pulling
⇧W: Show or hide the pins

Measure

Drag: Measure from A to B; the ends snap to nodes, segments, node lines and unit lines
⇧Drag: Measure in 0, 45 and 90° steps
Esc: Clear the measurement

Nodes

⌫: Delete the selection (Del too)
⇧⌫: Smart delete, the curve keeps its shape
123: Corner, smooth, genius
⌘A: Select every node of the path
⌘⇧A: Deselect
Arrows: Nudge 1 px (a module with the grid on, a minor step with a snapping unit)
⇧Arrows: Nudge one module (1 px with the grid on or a snapping unit)
⌥Arrows: Slide the selected nodes on their rails
O: Open corner
⇧O: Reconnect
B: Break at the node
M: Match handle, or symmetrize the path
X: Cycle the mirror mode

Pointer

Drag: On a curved segment: mold it
Drag: On a straight segment: push it, ends on their rails
⌥Drag: On a segment: mold it, straight ones too
⌥Click: On a segment: insert a node
⇧Click: On a segment: insert at the extremum
⌥Drag: On a node: slide it along a neighbouring segment (corners stay)
⌥Drag: On a selected node: slide the set on its rails
⌘Drag: On a node: power nudge, handles follow
Drag: On the Tunni point: handle tension
2× Click: On the Tunni point: balance the segment
Drag: On empty stage: marquee, ⇧ adds
⇧Click: On a path or list row: add to the selection
Drag: On a selected path: move the whole selection
Drag: Rectangle: corner to corner
⇧Drag: Rectangle: a square
⌥Drag: Rectangle: from the centre

Path

↵: Finish the draft
Esc: Cancel the draft, deselect
E: Add extrema
T: Fix all: Doctor fixes and tidy
J: Join open ends
U: Reverse
⇧H: Harmonize handles
⇧⌥H: Harmonize nodes
+: Fit Curve +2
−: Fit Curve −2
⌘D: Duplicate the path

View

F: Fit to view
C: Curvature comb
G: Grid
S: Snap
Esc: Cancel a unit origin or overshoot line pick
A: Construction grid
Scroll: Zoom, pinch for fine steps

File

⌘Z: Undo
⌘⇧Z: Redo
⌘E: Export SVG
⌘⇧C: Copy SVG
⌘⇧E: Export PNG at 2×
⌘⇧S: Save a version
⌘V: Paste SVG
?: This panel

⌘ is Ctrl on Windows and Linux. Alt-click a segment to insert a point. Shift-click inserts at its extremum.