Hi all
I'm trying to get some measure of the amount of texture when using spherical harmonics.
As per
here, I've entered
PO_Spherical_Harmonics(sh, 8)
Texture_Index(sh, 0)
into my input file, but the texture index is being returned as 1.
What am I doing wrong?
Also, is there a reference for this as to what it is actually doing?
.
I'm using 8th order harmonics on corundum (R-3C). The refined values are
PO_Spherical_Harmonics(sh, 8 load sh_Cij_prm {
y00 !sh_c00 1.00000
y20 sh_c20 3.45732`
y40 sh_c40 3.21439`
y43m sh_c43m 0.06270`
y60 sh_c60 2.30631`
y63m sh_c63m -0.08453`
y66p sh_c66p -0.03784`
y80 sh_c80 1.27055`
y83m sh_c83m 0.23360`
y86p sh_c86p -0.04219`
} )
If I add what I think Texture_Index is doing, I get the following:
prm = 1 + (1/5) (sh_c20^2) +
(1/9) (sh_c40^2 + sh_c43m^2) +
(1/13) (sh_c60^2 + sh_c63m^2 + sh_c66p^2) +
(1/17) (sh_c80^2 + sh_c83m^2 + sh_c86p^2); : 5.04731`