Chapter+6

=Chapter 6=

toc



"Reverse Perspective" transformation
Patrick Hughes media type="youtube" key="yhnIGNHuORs" height="385" width="480"

Paleo-camera and the origins of art: camera obscura transformation
Go into a very dark room on a bright day. Make a small hole in a window cover and look at the opposite wall. What do you see? Magic! There in full color and movement will be the world outside the window — upside down!

media type="youtube" key="-PxOlAfPO40" height="385" width="480"



Inversive geometry
media type="youtube" key="JX3VmDgiFnY" height="385" width="480"

Turning a plane inside out through a circle, in three easy steps:
 * 1) Pick a point. Make a circle centered in the point, with the radius equal to the distance from the point to the center of your inversion circle.
 * 2) Make two circles centered on intersections of that new circle with the inversion circle, and the radius of the inversion circle.
 * 3) These two circles intersect in the inversion of your point! Now repeat for every point in the plane!

http://demonstrations.wolfram.com/InversiveGeometryIVInvertingAPointWithACompassInThreeSteps/