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Chapter 31: Ellipse Reference
real get linear eccentricity (void)
228
[const function]
Returns linear_eccentricity.
real get numerical eccentricity (void)
[const function]
Returns numerical_eccentricity.
real get axis v (void)
real get axis v (void)
[Function]
[const function]
Calculates and returns the value of axis_h.
get_axis_v() first checks if the Ellipse is still elliptical, using is_elliptical()
(see Section 31.7 [Ellipse Reference; Querying], page 227). Operations such as
scale() and shear() can cause an Ellipse to become non-elliptical. If this is the
case, this function returns INVALID_REAL.
If the Ellipse is still elliptical, axis_v is recalculated and returned. In the non-const
version, axis_v is also reset to the new value.
real get axis h (void)
real get axis h (void)
[Function]
[const function]
Calculates and returns the value of axis_h.
get_axis_h() first checks if the Ellipse is still elliptical, using is_elliptical()
(see Section 31.7 [Ellipse Reference; Querying], page 227). Operations such as
scale() and shear() can cause an Ellipse to become non-elliptical. If this is the
case, this function returns INVALID_REAL.
If the Ellipse is still elliptical, axis_h is recalculated and returned. In the non-const
version, axis_h is also reset to the new value.
signed short location (Point p )
[const virtual function]
Returns a value l indicating the location of the Point argument p with respect to the
Ellipse.
Let e stand for the Ellipse. The return values are as follows:
0
p lies on the perimeter of e.
1
p lies in the plane of e, within its perimeter.
-1
p lies in the plane of e, outside its perimeter.
-2
p and e do not lie in the same plane.
-3
e is not elliptical, possibly due to having been transformed.
Ellipse e(origin, 3, 5, 45, 15, 3);
e.shift(2, 1, 1);
Point A = e.get_point(7);
cout << e.location(A);
a 0
Point B = center.mediate(e.get_point(2));
cout << e.location(B);
a 1
Point C = center.mediate(e.get_point(2), 1.5);
cout << e.location(C);