[EDIT]Nevermind, I've found the answer by reading one more time the linked paper.
I'm currently implementing ambient lighting using spherical harmonics, inspired by this paper, and I'm looking for some details.
Basically, I don't understand how they do the real time relighting stuff described in slides 7 to 10
Right now I'm rendering a bunch of environment cube maps with my scene rendered with only the textures color, no lighting at all.
Then I compute the spherical harmonics for the cube maps, and the final lighting shader looks like this:
//final lighting code float4 finalColor = irradiance*texture + NDotL * shadows * texture;
This gives nice results but I don't think this is the right way to do it, and I should render my scene with full shadowing, using something like:
//cubemap render code float4 color = NDotL * shadows * texture;
Which seems to be a better way, as lit zones will "generate" more irradiance than unlit ones.
And then change the final lighting equation to something like that:
//final lighting code float4 finalColor = texture+irradiance+NDotL * shadows * texture;
But this bothers me because if the light direction changes, I need to recompute all the cube maps, which is not "real time friendly".
So what am I missing ?
Thank you very much for any help !