o o
   
   
   
u u

Incidence matrix according to Dynkin symbol

x u3o

. . . | 6 | 1 2 | 2 1
------+---+-----+----
x . . | 2 | 3 * | 2 0
. u . | 2 | * 6 | 1 1
------+---+-----+----
x u . | 4 | 2 2 | 3 *
. u3o | 3 | 0 3 | * 2

uu3oo&#x   → height = 1
(u-{3} || u-{3})

o.3o.    | 3 * | 2 1 0 | 1 2 0
.o3.o    | * 3 | 0 1 2 | 0 2 1
---------+-----+-------+------
u. ..    | 2 0 | 3 * * | 1 1 0
oo3oo&#x | 1 1 | * 3 * | 0 2 0
.u ..    | 0 2 | * * 3 | 0 1 1
---------+-----+-------+------
u.3o.    | 3 0 | 3 0 0 | 1 * *
uu ..&#x | 2 2 | 1 2 1 | * 3 *
.u3.o    | 0 3 | 0 0 3 | * * 1

xx ou&#u   → height = sqrt(3) = 1.732051
(line || (x,u)-{4})

o. o.    | 2 * | 1 2 0 0 | 2 1 0
.o .o    | * 4 | 0 1 1 1 | 1 1 1
---------+-----+---------+------
x. ..    | 2 0 | 1 * * * | 2 0 0
oo oo&#u | 1 1 | * 4 * * | 1 1 0
.x ..    | 0 2 | * * 2 * | 1 0 1
.. .u    | 0 2 | * * * 2 | 0 1 1
---------+-----+---------+------
xx ..&#u | 2 2 | 1 2 1 0 | 2 * *
.. ou&#u | 1 2 | 0 2 0 1 | * 2 *
.x .u    | 0 4 | 0 0 2 2 | * * 1

xxx&#u   → all heights = 2
(line || (line || line))

o..    | 2 * * | 1 1 1 0 0 0 | 1 1 1 0
.o.    | * 2 * | 0 1 0 1 1 0 | 1 0 1 1
..o    | * * 2 | 0 0 1 0 1 1 | 0 1 1 1
-------+-------+-------------+--------
x..    | 2 0 0 | 1 * * * * * | 1 1 0 0
oo.&#u | 1 1 0 | * 2 * * * * | 1 0 1 0
o.o&#u | 1 0 1 | * * 2 * * * | 0 1 1 0
.x.    | 0 2 0 | * * * 1 * * | 1 0 0 1
.oo&#u | 0 1 1 | * * * * 2 * | 0 0 1 1
..x    | 0 0 2 | * * * * * 1 | 0 1 0 1
-------+-------+-------------+--------
xx.&#u | 2 2 0 | 1 2 0 1 0 0 | 1 * * *
x.x&#u | 2 0 2 | 1 0 2 0 0 1 | * 1 * *
ooo&#u | 1 1 1 | 0 1 1 0 1 0 | * * 2 *
.xx&#u | 0 2 2 | 0 0 0 1 2 1 | * * * 1