CGTalk - GI dont lit the shaded surface, why?

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ninus3d

02-28-2005, 10:03 AM

What factors do I need to be aware of when it comes to GI photons?
I have a simple indoor officescene where i have 3 spots reflect around a bunch of photons and this is working great for the whole scene except the walls!

Now, quite obvious so is it the shader for the wall's fault that nothing shows, but what am I supposed to tweak here?
Its a lambert shader with mib_color_mixture inputs in the colorchannel, wich again has a dirtmap (my guessing as the troublemaker,but why?) and a normal lambert, and the orginial lambert has a nosiefilter added to the bumpmapchannel to kinda fake overpainted concrete!

As I said I guessed the reason its not working is the dirtmap, but why is this and how do I overcome this problem? :shrug:

Any help would rocky my world! :buttrock:

Ultrasonic

02-28-2005, 10:06 AM

Have you tried to add a simple dgs_photon shader to your walls???
This could also speed up your rendertimes...

c ya
Oli

ninus3d

02-28-2005, 10:12 AM

k, started to play around with it now but how do I use this? :P

Ultrasonic

02-28-2005, 12:25 PM

Put the dgs_photon in the photon_shader slot of your wall's shadingroup..then set diffuse to some light grey and Glossy/spec to zero...this should catch the photons on your wall...

ninus3d

03-02-2005, 01:07 PM

I dont quite understand how i am to connect the dgs_material_photon into my shadernetwork..
Can anyone please give me some examples regarding this?

cpan

03-02-2005, 01:45 PM

Open the AE window and in the 'mental ray' section you'll see a slot called 'photon material' or something like this. Now click the map button and find the dgs_material_photon shader. If you've allready created this photon shader you can either use the hypershade and drag the dgs_mat_phot onto your SG then choose photon material or you could use my shaderList script to make connections within AE much easier.

ninus3d

03-03-2005, 05:00 AM

Well, the mib_colormix is connected to the colorchannel of a simple phong shader wich I have applied to the surface....
The only thing here about a photonthingie are under the "derive from maya" section and im not clear as of to wich of those settings I am to insert the photon map onto!
Color? Specular? Shinyness? Reflectivity etc?

All of this are, as you probably know, under "photon attributes" for the phong shader!
Now, are there a smarter way of doing this to?
Maybe have the finalshader (the one i insert the colorchannel from mib_color_mix into)?

ninus3d

03-03-2005, 05:36 AM

Well, I did a little google based upon what you said (Everything I found in the manual didnt provide me with much) and came to a site wich basicly show what I THINK you mean

http://www.motiondesign.biz/vol_4.html

But I havent found something like this at all? Have a look at my Hypershade

http://home.online.no/~jdybdal/HyperShade.jpg

Where would I find the "Photon shader" attribute here?

T-R

03-03-2005, 05:57 AM

Check out the link.

http://img140.exs.cx/my.php?loc=img140&image=mr8oz.jpg

ninus3d

03-03-2005, 07:02 AM

Thanks for all the help guys! I finally did it now and it works like a charm :)

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