MR ambient light shader

[victor]

Um... could you be a little more specific when linking to a 160 page PDF? ;)

[joie]

Well, the one I search for is the ambient environment shader, page 91, I don´t bother if it does ambient occlussion or not, I just want ambient environment light, that´s it.

Thank´s for your help in advance.

[T-R]

I think the dirtmap shader did this. If you checked off use enviornment it would only pick up the colours from the surrounding enviornment without occlusion.

[joie]

Yes, Dirtmap does it, but it is reaaaaaaaaaally slow, I don´t know why and I don´t remember right know, but I think it does Occlussion even in ambient anvironment light mode..., correct me if I´m wrong.

Although there are some new shaders and textures in MAYA7 related to occlussion and bent normals, do you know if anyone does what I want?, I tried the bent normals node and does something pretty similar, but I´m not sure if it is what I ask for...

[brunner]

I may be wrong, but i think mib_amb_occlusion does that too, if you set the 'mode' to 1 (environment sampling).

[joie]

Argh, are you serious?, I´ll try that tomorrow...

Thank´s.

[joie]

Yes, you were right (I couldn´t go home till I tried that).

Although is as slow as Dirtmap and DOES occlussion (you can set the max distance to almost zero and it is faster and doesn´t occlude), I´ll keep trying.

Thank´s.

[Splin]

Everything has its price. You say it is slow, to what are you comparing? There is no "more faster" way to environment occ...its been like that long time already now. But keep in mind, for static objects you just have to render it for one frame. And for characters, it is a great way to break them away from scene and light/render separately while all the lighting conditions stay coherent. And thru that man can win enormeous amount of time, test it out and practise. And if it is still too slow..find a renderfarm..I guess there should be one pretty cose to you :)

[joie]

Well, I think ~4 minutes for a sphere and a floor at 720x576 pixels is pretty slow..., I think I should test more with softened environments...

[floze]

Although I cant open the file youre linking to, I guess youre referring to a technique that allows you to relight your scene using an evnironment map, baked bent normals (in object space) and baked occlusion. Paolo Berto showed us this at the siggraph masterclasses this year. Unfortunately I dont have access to maya 7 yet, but there should be a shader called mib_bentnormal_env. You should be able to quickly relight your scene based on an environment map by feeding previously baked bent normals and baked occlusion into this shader.

Here's another paper describing this technique:

http://www.debevec.org/HDRI2004/landis-S2002-course16-prodreadyGI.pdf
edit: Maybe the paper above overlaps with the paper you linked..?

[Hasnz]

i think u are looking for somthing that is known as the IBI shader in renderman . and yes it is truly amazing how it gives u a coloured ambient rather than the usual flat ones we usually get .. AND ... it is as very fast . even if u apply an hdri to the env map .

U can cheat a similar technique ( if ure looking for this one ) by applying a very blurred hdri map to the ambient color (spherical map ) . . and playing with the color offset to get diff ints.

usually multiplying this pass with an occ pass gives u a pretty decent GI look .

just my two cents in if thats what the case .

[Splin]

One more thing..dont forget to convolute and white point balance your hdr probe what you are using for your env ambient pass.

[victor]

Although is as slow as Dirtmap and DOES occlussion (you can set the max distance to almost zero and it is faster and doesn´t occlude), I´ll keep trying.The issue with speed has less to do with the oocclusion than it does with the number of samples. If you set those near 1, and the spread near 0, and if you're using Maya 7, also set the Id_inclexcl to something other than 0 (that will ignore all objects), you should get what you're looking for.

[joie]

Thank´s all for the info, I´ll check those things when I have time, I´m pretty busy at the mooment, and will post my (luckily) success, of course.

:)

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