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Reference

SNAP in AutoCAD

How AutoCAD's SNAP (SN, F9) works: the cursor held to a lattice at the spacing you set, Aspect for X and Y apart, and polar snap. Try it free online.

Snap mode holds the cursor to a lattice: each pick lands on the nearest of its points, so with a spacing of 10 a click at 13,7 is 10,10. The lattice is the current UCS's, from its origin along its axes. F9 turns snap mode on and off, writing <Snap on> or <Snap off>, and so does its button on the status bar. Only picks are rounded: a typed coordinate is taken as typed, and an object snap wins over the lattice. The grid (F7) draws a lattice of its own, and shows it whether snap is on or off.

The SNAP command sets the spacing: type it, or give two points that far apart, and snap mode turns on with it in X and Y. Enter turns it on as it is. A spacing of 0 or below is refused with Value must be positive and nonzero.. Typed with an apostrophe, 'SNAP, it works inside another command. Snap mode and its spacing are saved with the drawing, and U takes a SNAP back.

The status bar's Snap menu chooses Polar Snap instead: along a polar tracking path the cursor steps by POLARDIST or, while POLARDIST is 0, by the snap's X spacing.

At the command line

The engine draws it and writes its history as you would type it: the prompts in AutoCAD 2027's order, with the same option letters.

SNAP 10 with the grid on, then LINE picked off the lattice: every point lands on it, and so does the cursor.
  1. Command: SNAP
  2. Specify snap spacing or [ON/OFF/Aspect] <10.00>: 10
  3. Command: LINE
  4. Specify first point:
  5. Specify next point or [Undo]:
  6. Specify next point or [Undo]:
SNAP 10 with the grid on, then LINE picked off the lattice: every point lands on it, and so does the cursor.

Options

ON

Turns snap mode on with the current spacing, as Enter does.

OFF (OF)

Turns snap mode off; the spacing is kept.

Aspect (A)

Asks for a horizontal spacing, then a vertical one, and turns snap mode on: a lattice taller or wider than it is square. The prompt's default is then Aspect, so Enter asks them again.

What it does not do yet

Style, isometric snap, and Type, grid or polar, at the prompt: the status bar's menu chooses the type. Legacy, the hidden Rotate (SNAPANG) and SNAPBASE. A negative POLARDIST, which AutoCAD's polar snap takes as its size: −10 steps 10.

What it does and still lacks, in detail (in English)

Questions

What is the shortcut for SNAP in AutoCAD?

F9 turns snap mode on and off. The command is SN, then Enter or Space, to set the spacing; the full name works too, and _SNAP in any language of AutoCAD.

What is the difference between SNAP and OSNAP?

Snap mode rounds the cursor to a lattice of points in space. Object snaps (F3) lock it to points on objects, endpoints, midpoints, centres. They work together, and an object snap wins where both find a point.

Why does my cursor jump in steps?

Snap mode is on: press F9, or the status bar's snap button, to turn it off. Set a smaller spacing with SNAP if you want the steps finer.

How do I set different X and Y snap spacing?

Run SNAP, choose Aspect, and give the horizontal spacing, then the vertical one.

Is there an isometric snap?

Not yet: SNAP's Style option, which turns the lattice for isometric drawing, is not offered.

Related commands