Tool manual

How to use the Parametric Shape tool

The Parametric Shape tool draws shapes defined by numbers: rectangles with a different radius on each corner, rounded polygons and stars.

Where to find it

It is in the toolbar, in one slot with Shape. Right-click the slot, or press and hold it, to choose between them. Press Shift+U until it is selected (U on its own picks Shape).

How to use it

1. Choose the tool. Right-click the shapes slot in the toolbar and pick Parametric Shape, or press Shift+U past the last shape.
2. Pick a shape. Choose Rectangle, Ellipse, Polygon or Star.
3. Set the numbers. For a rectangle, set each corner radius; for a polygon or star, the sides and corner radius.
4. Drag. Drag on the canvas. Shift keeps the proportions even; Alt draws from the centre.

Options bar settings

• Top left, Top right, Bottom right, Bottom left: Rectangles: the radius of each corner on its own.
• Sides and Corner radius: Polygons and stars: how many points, and how round they are.
• Inner radius: Stars: how deep the cuts between the points go.
• Fill, Stroke, Size: As with the Shape tool: fill, outline, and free or fixed size.

Tips and common mistakes

• A star with a high Inner radius and many sides makes a badge or seal shape.
• Use Fixed size when you need several identical shapes.

Related

• How to use the Shape tool
• How to use the Pen tool
• How to use the Direct Selection tool

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Checked 13 November 2026 in the current editor.

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