Graphics Reference
In-Depth Information
⎡
⎤
c
β
0
−
s
β
R
−
1
⎣
⎦
rotate the frame
β
about the
y
-axis
β,y
=
01
0
s
β
0
c
β
⎡
⎤
c
γ
s
γ
0
R
−
1
⎣
⎦
rotate the frame
γ
about the
z
-axis
γ,z
=
−
s
γ
c
γ
0
001
where
c
α
=
sin
α
,etc.
Remember that the right-most transform is applied first and the left-most trans-
form last. In terms of angles, the sequence is always
α
,
β
,
γ
.
For each composite transform you can verify that when
α
cos
α
and
s
α
=
=
β
=
γ
=
0 the result
is the identity transform
I
.
We now examine the twelve combinations in turn.