1G
1
G
A polynomial curve is a Pythagorean-hodograph curve if + is the square of another polynomial. The lowest-degree curves satisfying this condition are PH-cubics. They are represented here in Bézier form. The degrees of freedom of such a curve allow using it to solve a partial Hermite interpolation problem: the boundary points and the tangent directions can be specified, but not the speeds at these points. Some situations have no solutions.
M(t)=(x(t),y(t))
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