Node: Performing Transformations on Ellipses, Next: , Previous: Ellipse Constructors and Setting Functions, Up: Ellipse Reference

Performing Transformations

Transform do_transform (const Transform& t, [bool check = false]) Virtual function
Performs a transformation on an Ellipse. The Points on the Ellipse are multiplied by t. Then, if check is true, is_elliptical() is called on the Ellipse. If the transformation has caused it to become non-elliptical, axis_h and axis_v are set to INVALID_REAL, and a warning is issued to stderr. center, focus0, and focus1 are not set to INVALID_POINT. They may may no longer really be the center and foci of the (non-elliptical) Ellipse, but they may have some use for the programmer and/or user.

If check is true, and the transformation does not cause *this to become non-elliptical, axis_h, axis_v, linear_eccentricity, numerical_eccentricity, focus0, and focus1 are recalculated.