Teapots are used for rendering tests because they have many features that interact with light in different ways.
Many different normals are exposed simultaneously.
Here's some screenshots from a 3D engine I wrote.
As you can see the teapot has:
Slow large curves (body)
Fast small curves (spout, handle, lid handle)
Hard edges (top rim, lid, spout hole)
Overlap (handle, spout, lid)
Down facing normals (bottom of body, bottom of spout, bottom of handle, bottom of lid handle)
multiple pieces (body and lid)
Inner shell (spout hole, top)
Self Casting shadow (not shown here, but it is able too unlike a box)
etc
These are good lessons to learn how to render when drawing in 2D, and are a useful collection of features when running tests in 3D.
This lets you more accurately test a shader than using something simple like a cube.
Also a teapot is one of the DirectX default meshes that you can draw with a single function call.
So its one of the first things you'll try when getting your graphics code running.
While it's not exactly a joke, it is funny.
Why is this? Is there any reason to draw a thousand teapots, instead of a thousand blenders?
You can draw blenders if you really want to!
Altho most blenders are see thru, so it adds an extra level of complexity.
It's an exercise, so the purpose isn't to be good at drawing teapots.
The purpose is to get better at drawing, managing time, completing a ridiculous task, being creative within limitations, etc.
While its not the most mind blowing drill, I think it's a good one.
Also keep in mind there aren't any rules.
You can draw a teapot in literally 10 seconds and it still counts.
Usually around 500 or so, people go crazy and start to get really creative.
A 1 week time limit is VERY HARSH so if it doesn't fit into your schedule don't worry about it.
But it's good to have some sort of time limit so that you learn to manage time with a quantity vs quality battle.
