Snapping

Locking points onto the drawing's own linework, onto your other takeoff, and onto angles.

Snapping is what makes a takeoff trace the drawing instead of approximating it. Points jump onto the linework, onto the corners of work you have already done, or onto a clean angle, so a pad traced at speed still closes on its real corners.

The four snap modes

Each is an on/off toggle that stays on until you turn it off, and they combine.

KeyModeSnaps to
F1Vector snapThe PDF's own linework - the lines the designer drew.
F2Point snapVertices of your other takeoff drawings on the page, including holes.
F3Page snapThe page itself.
F4Angle snappingClean angles from the last point.

With a tool armed but before the first point is placed, a marker previews what the next click will land on, so you can see the snap before you commit to it.

Tracing an edge

Snapping twice in a row onto the same shape's edge arms an edge trace: instead of placing two points and a straight line between them, the drawing follows that shape's edge. It is how a new area is made to share a boundary exactly with one already drawn, rather than nearly.

Snapping work you have already drawn

The four modes above act while you draw. Three separate commands act on a drawing that already exists, pulling it onto something once:

KeyAction
F8Snap Points
F7Snap Lines
F6Snap Pages

F1 to F4 are modes that stay on; F6 to F8 are one-shot actions on the current selection. Two rows of function keys that both say "snap" do different kinds of thing, which is worth knowing before you reach for one mid-trace.

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