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Jarred
05-18-04, 12:55 PM
anyone ever hear about this?

http://www.research.scea.com/gdc2003/spherical-harmonic-lighting.html

http://www.paulsprojects.net/opengl/sh/sh.html

because I have a feeling it's going to be popular

it basicly works off of an HDRI image, but simplifies it for realtime.

Nv40
05-18-04, 02:46 PM
anyone ever hear about this?

http://www.research.scea.com/gdc2003/spherical-harmonic-lighting.html

http://www.paulsprojects.net/opengl/sh/sh.html

because I have a feeling it's going to be popular

it basicly works off of an HDRI image, but simplifies it for realtime.


Unreal3 i think use it..

it simulates in some way Global Ilumination Lighting. where every object can behave as a source of light. dont know what are its limitations but every step to be closer to Professional GI lighting is always welcome. :)

Remi
05-22-04, 07:05 PM
In short: Aka PRT (Pre-computed Radiance Transfer) in real-time, you can have a look at Peter-Pike Sloan's home page at ms-research for more info (he's the main man behind it).

It's an excellent technique, great for soft (=low-frequency) lightings, and it does sub-surface scattering for free! The details (and tools to play with) are in the latest DX9 SDK...

To have a look at it, the easiest is to have a look at the the sub-surface scattering demo from ATI which is just showing this technique. What's new in this demo is that it use indoor lights and outdoor lighting on the one object with PRT. I haven't checked, but I believe that it should run correctly on any decent (by nowadays' standards) graphic card... It wasn't used before because it uses research works which was finished... ...last summer (although we saw Light-Field Mapping, another technique of the same familly but which requires static lighting - and for which a GF3 is enough).

Hopes this helps to clear things a bit... :)

Edge
05-23-04, 07:47 PM
Damn, they stole my idea...I KNEW I should've patented it...well OK my idea wasn't quite as complex but the basic theory was the same. Almost scary just how close real-time graphics are able to replicate real-life effects...pretty soon we won't have any reason to leave the house (well, as if we did before ;)).