Circular Approximation by Trigonometric Bézier Curves

We present a trigonometric scheme to approximate a
circular arc with its two end points and two end tangents/unit
tangents. A rational cubic trigonometric Bézier curve is constructed
whose end control points are defined by the end points of the circular
arc. Weight functions and the remaining control points of the cubic
trigonometric Bézier curve are estimated by variational approach to
reproduce a circular arc. The radius error is calculated and found less
than the existing techniques.

• Maria Hussin
• Malik Zawwar Hussain
• Mubashrah Saddiqa

• Control points
• rational trigonometric Bézier curves
• radius error
• shape measure
• weight functions.

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