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The center point of each selected circle, made if it is not already there.

Menu: Construct > Point: Center of Circle | In depth: Points

Select one or more circles and run it. You get their centers, selected and ready to use.

Unlike most of Construct, this is not a tool you click with. There is nothing to pick on the canvas: it reads the selection, does its work, and is finished.

This is the whole command, and it turns on how the circle came to be.

A circle you drew from a center already has that point. A center-radius circle, a center-point circle, a compass circle: in each case you put a point down first and the circle grew from it. Running the command on one of these simply selects the point that is already there. It does not mint a second point on top of the first, which would leave you with two points in the same place and nothing referencing one of them.

A circle whose center is worked out has no such point. A circle through three points, or a tangent circle, derives its center from the things it was built from, and that position was never a point you could reference, snap to, or measure from. This is where the command earns its place: it makes the point.

The made point is a constructed one. It belongs to that circle and follows it, rather than being dropped at wherever the center happened to be today.

Once a derived circle has been given its center, the command hands back the same point rather than making another. Run it on a mixed selection as often as you like and the count never grows.

• Anything that is not a circle in the selection is passed over. An arc has a center too, but this command takes circles only.
• A degenerate circle, one with no real radius to speak of, has no center to give and is skipped.

The selection you are left with afterward is exactly the centers, in the order the circles were in, so whatever you do next acts on those points and nothing else.

< Previous: Point: On Object | Next: Line: Perpendicular Bisector >

• Points: Intersection: the other Construct command that works on a selection rather than by clicking.
• Point: Center of Circle: drawing a circle from a center, the case where the point exists from the start.
• Points: what a constructed point is and how it differs from a free one.