Snapping While You Draw

When you draw, Pingendum doesn't place points wherever the cursor happens to be. It snaps them to whatever meaningful target is nearest — the end of an existing line, a circle's centre, a point along a curve, an origin axis, or the grid.

That's what makes drawn geometry actually connect. Two lines that merely look joined do not form a closed profile; two lines snapped to a shared endpoint do.

Snapping affects drawing only. It anchors the point a drawing tool is about to place, and doesn't change how the Select tool picks geometry.

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Prerequisites

Before you begin, ensure that:

• You've completed Drawing Basic Shapes and have some geometry to snap against.
• The Snap toggle in the grid/snap bar at the bottom of the window is on.

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What a Click Snaps To

There are three tiers, tried in order. The first tier with a target in range wins.

1. Existing geometry

Whatever is under the cursor, within a fixed screen-space radius:

Points get a tighter catch radius (about 6 pixels) than curve bodies (about 8), so aiming at an endpoint reliably gives you the endpoint rather than the line it belongs to. Both radii are measured in screen pixels and converted to sketch units at the current zoom, so snapping feels the same however far in or out you are.

2. The origin axes

With nothing else in range:

• Near the origin, the point snaps fully to (0, 0).
• Near the horizontal axis, the vertical coordinate locks to 0 while the horizontal one still follows the grid.
• Near the vertical axis, the opposite.

The axis you're capturing highlights as you approach it, so you can see the lock before you commit the click.

3. The grid

The fallback when nothing else is near.

Note: the Snap toggle governs tiers 2 and 3, not just the grid

Turning Snap off skips both the grid and the origin/axis locks. Only tier 1 — existing geometry — stays on, and it can't be turned off at all.

So Snap off means "snap to real geometry, and nowhere else": clicks that aren't near an endpoint, a centre or a curve land exactly where the cursor is, including near the origin.

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Which Snap Wins

The tiers above are strictly ordered: geometry → axes → grid. Within the first tier, a point beats a curve, and among several candidates the nearest wins.

So if an endpoint and a curve body are both under the cursor, you get the endpoint. If an endpoint and the origin are both in range, you get the endpoint — geometry outranks the axes.

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How This Interacts With Other Tools

• The transform tools. The base and destination clicks of Translate, Rotate and Scale obey these snaps, so copies can land on exact relative positions rather than by eye.
• The Select tool. Snapping is inactive while Select is active. Hovering near an endpoint in Select mode won't shift your cursor.
• Auto H/V. Separate from snapping: it constrains a drawn segment to horizontal or vertical, rather than moving a point to a target. Both can act on the same click.

Tip

Snapping to an existing endpoint places the point at the same location, but whether the two are genuinely joined depends on the tool. If a profile isn't closing, run Validate Sketch (Diagnosing Sketches) — it reports open endpoints and near-miss gaps that look connected but aren't.

Note: midpoint, intersection, quadrant, tangent and perpendicular snaps do not exist yet

Other CAD packages offer snaps that compute a target rather than picking an existing one — the exact middle of a line, where two curves cross, the top of a circle, or the point that makes a new line tangent to an arc.

Pingendum's design specification describes these, but they are not implemented in any current build. Hover resolution recognises only endpoints, centres and points on a curve. If you need the midpoint of a line, draw to it roughly and add a Midpoint constraint afterward (The Complete Constraint Toolkit) — the constraint will move the point to the exact position and hold it there.

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Next Steps

You now know how to:

• Predict what a drawing click will snap to
• Use endpoint snapping to build profiles that genuinely close
• Recognize the axis and origin locks, and turn grid snapping off when you don't want it
• Reach for a constraint when the snap you want doesn't exist

That completes the precision, feedback, and quality tools that turn a working sketch into a dependable one. The next part covers organizing a finished drawing and getting it out of Pingendum.

Next: Working with Layers