Here's a "camera obscura", which is just a little box (or room) with a
hole in one side. Light shines through the hole, and falls on a
sheet of tracing paper to generate the image. Note how the
image in the box is flipped vertically and horizontally.
You can also build a mirror into the camera obscura, which flips the image vertically
The question for today: if a point is sitting at in 3D space at
coordinates (x,y,z), what 2D point (X,Y) does it project to on the
plane of a camera obscura?
