See section 12.14.7 for inversions in space.
Given a circle C with center O and radius r, the inversion of a point A with respect to C is the point A′ on the ray OA satisfying OA·OA′ = r2.
The inversion command takes two or three arguments.
If inversion has two arguments, they are a point (the center
of inversion) and a real number (the radius).
inversion returns a new command which performs the
inversion.
Input:
then:
Output:
then:
Output:
If inversion has three arguments, the first two arguments are a
point and number as above, and the third argument is a geometric
object. inversion returns and draws the inverted object.
Input:
Output:
Input:
Output: