RE: [Algorithms] Re: Is there such a thing as spherical harmonic lighting for characters?

[Tom F. <tom...@ee...>]

The self-shadowing bumpmaps paper at www.eelpi.gotdns.org/papers.html =
has
some comparisons of the number of directions for horizon maps. 4 can =
look OK
for rough surface textures like wood and stone and stuff like that, but =
if
there are any recognisable features on the surface, it's pretty poor.
(oops... the PDF version was missing before - fixed)

TomF.

> -----Original Message-----
> From: gda...@li...=20
> [mailto:gda...@li...] On=20
> Behalf Of Tomas Arce
> Sent: 12 April 2004 23:35
> To: gda...@li...
> Subject: [Algorithms] Re: Is there such a thing as spherical=20
> harmonic lighting for characters?
>=20
>=20
>=20
> TomF <--- I don't know about whether you need 9 directions=20
> for the Horizon
> maps. The only implementations I have ever seem were done=20
> with 4 (ex; DX9
> demo DumpSelfShadow). I can't say whether it needs more than=20
> that but I
> guess I will take your word for it.
>=20
> Ignacio_Casta <--- Remember my presentation? (www.zen-x.net)=20
> I think the
> hold pipe line will work very similar to the local space=20
> bumb-map for the
> characters. Where you take the SH light into the local space=20
> of the bones
> (in CPU) then upload it into the vertex shader. Then skin the light SH
> vector. Then you should have computed the RT SH vector in the=20
> local space of
> the object. Then, just do the dot product. So the work is=20
> divided between
> CPU and GS. How many CPUs are we going to get in the xbox2? ;-)
>=20
> How many dimensions you think you will need to encode a=20
> sufficient accurate
> SH vector? tom, I think you like a 9d SH vector right?=20
>=20
> Tomas
>=20
> PS. Encoding anything more than one parameter ex; luminance=20
> is just crazy
> talk. ;-)