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An object c of type Sphere_circle is an oriented great circle on the surface of a unit sphere. Such circles correspond to the intersection of an oriented plane (that contains the origin) and the surface of S2. The orientation of the great circle is that of a counterclockwise walk along the circle as seen from the positive halfspace of the oriented plane.
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ring type.
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plane a Sphere_circle lies in.
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creates some great circle.
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If p and q are
opposite of each other, then we create the unique great circle on S2
which contains p and q. This circle is oriented such
that a walk along c meets p just before the shorter segment
between p and q. If p and q are opposite of each other then
we create any great circle that contains p and q.
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creates the
circle corresponding to the plane h.
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creates the circle orthogonal to the vector (x,y,z).
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creates a great circle orthogonal to c that contains p.
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| Returns a sphere circle in the oppostie direction of c. |
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| returns true iff c contains p. |
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| returns the plane supporting c. |
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| returns the point that is the pole of the hemisphere left of c. |
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| returns true iff c1 and c2 are equal as unoriented circles. | ||