Snapping
The magnet: what snaps to what, how close you have to be, and which tools obey it.
Snapping pulls whatever you are dragging onto a nearby grid line, vertex or edge, so shapes meet exactly instead of nearly. It is one master toggle plus three sources, and it is off until you turn it on.
Turning it on
The magnet button on the main toolbar is the master switch. It starts off, and your choice is remembered between sessions. Next to it is a small arrow that opens the snap options: Grid, Vertex and Line, with Select All below them to switch on all three at once.
| Option | Default | What it snaps to |
|---|---|---|
| Snapping | Off | The master switch: with it off, nothing below applies |
| Grid | On | The nearest grid intersection, at the current Grid Spacing |
| Vertex | On | Any point of any visible Shape layer |
| Line | Off | The closest position along any visible path segment |
How close is close enough
The snap radius is 8 pixels on screen, not in the document. Because it is measured on screen, zooming in makes snapping more precise rather than more eager: at 800% those 8 pixels cover an eighth of the document distance they cover at 100%.
All three sources are searched at once and the nearest candidate wins, so a vertex a pixel closer than a grid line beats the grid line.
Which tools snap
Snapping applies where you are positioning something:
- Select: while you drag layers around
- Transform: while you drag the body of the selection, but not while you scale, rotate or move the anchor
- Pen: both when you place a point and when you drag its handles
- Node: see below, it has its own rules
- Rectangle, Ellipse, Polygon, Star and Line: the start and the end of the drag
Everything else ignores the magnet entirely: Pencil, Brush, Eraser, Smudge, Knife, Fill, Marquee, Magic Wand, Eyedropper and Gradient never snap. Painting tools are meant to follow your hand.
Node snapping and Weld
The Node tool does not use the shared radius. While you drag a vertex it snaps within 14 screen pixels to any vertex or edge of any visible Shape layer, ignoring the vertex you are dragging and the two edges attached to it. A snapped vertex lands exactly on its target rather than keeping the offset you grabbed it by, and the target is marked with an amber ring.
Turning on Weld in the Node options forces this snapping on even when the magnet is off, and narrows the targets to vertices only. Edges stop attracting. Weld decides what happens on release: with it on, dropping a snapped vertex onto another vertex merges the two structurally.
Bone snapping
The Bone tool has its own magnet, again separate from the toolbar one. Its Snap checkbox, which is only offered in Edit mode, pulls the ends of a bone onto the start or end of any other bone within 15 screen pixels. While you are drawing a new bone you can also get the same snap on demand by holding Ctrl. Where a snap has already locked, it wins over the Shift angle constraint.
Working without it
Snapping is a positioning aid, not a constraint system: it never rewrites geometry you are not dragging, and it leaves no trace in the file. If a shape refuses to land where you want, switch the magnet off for that one move rather than fighting it. The button is one click away and the setting survives a restart.