Stereo projection of a spherical dodecahedron
Step 3: Use 120 and 30 degree trick. Just plot
a point on a vertical line. The point marked
center is the center of the circle of flower
leaves.
Ste
In last class we found that for
g w f X f
1
a bi
w a bi
,
2a 2b cos a 2 b 2 1 sin i
a 2 b 2 1 2b sin a 2 b 2 1 cos
Facts:
p, q, r , s
If
u, v
, that depends on
, then
uv u v
but not on
w
, so that
pw q
g w
rw s
.
and
uv u v
.
If
w a bi
, then
ww a 2
In the last classes we define three different sets in
A
x , y , 0, 0 | x
1
1
2
1
4
:
y12 1
B 0, 0, x2 , y2 | x2 2 y2 2 1
C
x , y ,x , y | x
1
1
2
2
1
x2 , y1 y2 , x12 y12 x2 2 y2 2 1
Then we look at their stereographic projection onto
3
, and get the